Life Cycle Analysis and Life Cycle Costing Tools Applied to Post-frame Building Systems
April 2011
Final Report
Daniel P. Hindman
Associate Professor, Virginia Tech
Abstract
Green building has become one of the most dynamic market forces in the area of construction. While
post-frame buildings are considered sustainable because of the efficient use of materials and other factors,
little documentation of the reduced environmental and energy impacts of post-frame buildings exists. The
purpose of this project is to develop life cycle analysis (LCA) and life cycle costing (LCC) tools with
examples to account for the sustainable attributes of post-frame construction. Currently, no commercial
LCA or LCC programs include post-frame construction. However, an equivalent LCA for post-frame
buildings can be performed considering a 2x6 conventional wall structure and using the input elements of
the LCA program. A spreadsheet application was developed for conversion of a post-frame building to an
equivalent conventional construction wall and roof system. This same practice could not be duplicated for
the LCC programs. Three example buildings showing different post-frame constructions were presented
with an accompanying spreadsheet. The output environmental indicators and comparison tools of the
LCA were also presented.
Table of Contents ………………………………………………………………….….
2
1.0 Introduction ………………………………………………………………………..
3
1.1 Life Cycle Analysis (LCA) Definition …………………………………….
4
1.2 Life Cycle Costing (LCC) Definition ……………………………………..
6
2.0 Goals and Objectives ………………………………………………………………
7
3.0 Methods and Results …………………………………………………………….
8
3.1 Objective 1: LCA Models for Post-frame ………………………………..
8
3.1.1 Conventional Construction Equivalency Idea ………………………. 9
3.1.2 Calculation of Post-frame Wall Volume ………………………..
9
3.1.3 Calculation of 2x6 Equivalent Wall Volume ……………………
11
3.1.4 Roof Calculations ……………………………………………….
12
3.1.5 Spreadsheet Details …………………………………………….
13
3.2 Objective 2: LCC Models for Post-frame ………………………………
16
3.3 Objective 3: LCA Building Examples ………………………………….
17
3.3.1 Building #1 Description: Open Sided Machine Shed ………..
17
3.3.2 Building #1 LCA Results ……………………………………..
21
3.3.3 Building #2 Description: Residential Home ……….………...
24
3.3.4 Building #2 LCA Results ……………………………………..
26
3.3.5 Building #3 Description: Addition to Church ………………..
29
3.3.6 Building #3 LCA Results ……………………………………..
31
3.3.7 Comparison of LCA Results of Three Example Buildings …..
34
4.0 Conclusions ……………………………………………………………………..
36
5.0 References ………………………………………………………………………
37
6.0 Attachments …………………………………………………………………….
38
2
1.0 Introduction
Green building has become one of the most dynamic market forces in the area of construction.
Countless claims and colors of ‘green’ have been applied to products, systems and tools. Green
building is based on producing more sustainable buildings, in terms of the environmental inputs
and outputs, economic effects and social/human health effects. These concepts are difficult to
translate to actual measures.
The current way that the building community has to translate these concepts into buildings is the
various green building certification systems, including the LEED (Leadership in Energy and
Environmental Design) suite of programs, Green Globes, National Green Building Standard, and
the International Green Construction Code (IGCC) which is currently under development. These
green building certification systems encourage the use of materials assumed to have lower
environmental inputs and outputs, such as recycled materials, regionally produced materials and
rapidly renewable materials. Trusty and Horst (2002) discuss the fact that some of these
practices, such as the use of recycled products, do not guarantee that lower environmental inputs
will always be used. There is a need for a quantitative measure of the environmental effects of
alternative products or procedures in construction.
Of particular interest to the post-frame industry, many of the green building certification systems
DO NOT give credit for using innovative building systems. Building systems that differ from
conventional construction, such as post-frame, log homes, or even Passivhaus, currently receive
no additional points versus conventional construction practices. In much of the discussion of
green building materials, there is a decided lack of ‘systems thinking’ of how the building
elements work together to create an efficient envelope and structural system. Most emphasis is
placed upon the manufacture and assembly of individual materials.
The Post-frame Marketing Initiative (PFMI) has recognized that post-frame construction
represents an efficient (and green) building construction method and further work should
demonstrate the positive sustainable aspects of post-frame buildings. Recently, the NFBA
Technical and Research committee authored a white paper on this subject (Putting the ‘Green’
Into Post-frame: Accounting for Post-frame Construction in Green Building Certification
Systems http://www.nfba.org/files/public/Putting_the_Green_Into_Post_Frame_Final.pdf). The
white paper concluded that current methods of post-frame construction already contain many
green elements and builders should be aware and take advantage of these elements in their
marketing strategies. Green building advantages of post-frame included reduced site
disturbance, less use of wood to create the structural system, engineered systems for the roof
structure, and a building cavity with room to accommodate insulation to meet International
Energy Conservation Code (IECC) requirements, a must for many green building systems.
3
Subsequent white papers are planned to identify the specific green building certification system
requirements that post-frame can take advantage of.
One area of study to help support the claims of post-frame construction as a green building
method is the study of the building’s life cycle, using either life cycle analysis (LCA) or life
cycle costing (LCC). The life cycle of the building is defined as the collection of all inputs
(materials and energy) and outputs (product, waste, emissions) required by a structure for the
intended service life of a building. Typically, the life cycle is divided into stages including
manufacturing, construction, operation/maintenance, and end-of-life
(deconstruction/demolition). The study of the life cycle of a building is a complex and difficult
task, since each material has a separate and distinct life cycle. Any changes or different
decisions made for the materials and building systems can affect the results. A set of
assumptions about the structure must be made and the accuracy of life cycle assessment is
directly related to the validity of these assumptions. Also, the limitations of any life cycle study
must be carefully understood for accurate reporting.
1.1 Life Cycle Analysis (LCA) Definition
Life cycle analysis is the study and interpretation of the environmental inputs and outputs of a
building. LCA is a cataloging of all materials and energy used in a system, as well as the
products and waste created. An LCA system must be bounded much like a control volume in
thermodynamics problems to provide an accurate scope. Schenk (2000) provided a description
of the steps to complete an LCA. First, a life cycle inventory (LCI) must be prepared or accessed
for all materials used in the manufacture or construction of the final product. Next, the LCI data
is aggregated together using a particular set of equations depending upon the processing and
manufacture of the final product. From the aggregated data, a set of indicators are developed.
Finally, weighting factors are applied to each indicator to make decisions.
The LCI is the basic data set used to calculate a product LCA. For each individual material, the
LCI details the energy, material and waste used. LCI data have been collected by some
government organizations, but also many private organizations. LCI data must be kept current,
as changes in materials sources, manufacturing or processing may affect the basic amounts of
materials and energy used. One example of the need for current LCI data is the changing amount
of green power (solar, wind) available in the power grid. The amount of green power versus
fossil fuel power has a large effect upon the LCI data.
The aggregation phase of the data includes the compilation of the LCI data into a composite
form. For a product produced in a linear process, the LCI data may be simply added together.
However, building structures involve a more complex assembly of products. For whole-building
LCA, a variety of commercial LCA software packages exist which include the LCI data (or
access the data from various sources) and then aggregate the data. An LCA for a building is not
simply an addition of the properties due to the use of energy during the life cycle of the structure
4
to heat and cool. The location and exposure of individual building elements in walls and roofs
affects the individual material life cycles.
As a final step in the aggregation process, a series of environmental indicators are produced.
These indicators, according to Schenk (2000) are “not a measurement of actual environmental
effects. It [the indicator] is a measurement of something that most environmental scientists
believe will correlate well with the actual effects”. Table 1 lists some common indicators
determined by LCA programs. Most of the indicators are expressed as weights of specific
chemicals or materials which are considered environmental pollutants or the causes of global
environmental problems. Most commercial whole-building LCA programs produce these
environmental indicators or similar quantities.
Table 1: Indicators Found From LCA
Indicator Name
Global Warming Potential
Stratospheric Ozone Depletion
Ground Level Ozone
Acidification
Eutrophication
Aquatic Toxicity
Human Health
Fossil Fuel Depletion
Mineral Depletion
Water Depletion
Landuse
Units
Tons CO2 Equivalents
Tons Halon Equivalents
Tons Projected Ozone
Tons SO2 Equivalents
Tons Phosphate Equivalents
Tons Toxic Equivalents
Tons Toxic Equivalent
Tons Oil Equivalent
Tons Mineral Equivalent (by Mineral)
Volume of Water Equivalent (surface and
groundwater)
Equivalent area of endangered species and
non-endangered species habitat
The final step of conducting an LCA is the interpretation of these results. This is the most
difficult and complicated portion of the LCA process. Depending upon the use of the building,
geographical location, intended use, or other factors, the environmental indicators may be
weighted in different ways. For instance, the Ground Level Ozone indicator, which is related to
smog, may be weighted greater if a building is located in the Los Angeles, California area versus
the Midwest, where prevailing winds prevent the accumulation of ozone to produce smog in
large quantities. ISO 14040 is the international standard governing life cycle assessment claims.
The standards applied within ISO 14040 must be adhered to in order to formulate claims of one
product over another. The weighting system is another complication of comparing LCA results
between different kinds of buildings, especially in different geographical locations.
The previous description of LCA provides a general background of what constitutes an LCA. As
mentioned, there are a variety of commercial software tools available to help produce an LCA.
Each of these tools uses an LCI database and perform some aggregation of the building
components to produce a set of indicators similar to those in Table 1. LCA is not just considered
5
an ‘environmental need’ but has been used by some companies to help make decisions on
creating efficient production. The reduction of energy and material use is also the study of
manufacturing efficiency and reduction of waste. LCA results can be used for a variety of
decision making efforts, some of which are listed below.
•
•
•
•
•
•
•
•
Product Marketing
Supplier Decision Making
Design Choices or Product Use
Company Internal Benchmarking (Multiple Facilities or Divisions)
Year to Year Tracking of Energy and Material Use
Management and Policy (Importance of Environmental Indicators)
Green Building Certification Systems
Technical Data for Architects and Engineers
Several green building certification systems including the International Green Construction Code
(IGCC), the National Green Building Standard (ICC-700) and Green Globes include a wholebuilding LCA as an elective. The inclusion of LCA in these green building certification systems
has generated interest in attempting to create a quantifiable measure of sustainable buildings.
While no green building certification system requires a whole-building LCA at this time, green
building systems are undergoing constant evolution and growth with an increased need to
document the environmental effectiveness of buildings.
It is important to point out that LCA is just a tool to help describe the attributes of a particular
building system. LCA seems to lend itself to comparisons between types of buildings. While
comparisons can be made, any assumptions used in the system need to be documented and any
sources of bias must be eliminated. Comparisons of building types are difficult to conduct and
subject to bias and differences of opinion. A better use of LCA is to refine the environmental
inputs and outputs of building component choices – for instance, for two types of insulation with
the same R-value, what is the difference in environmental indicators? These types of decisions
tend to be more accurate and easier to interpret.
1.2 Life Cycle Costing (LCC) Definition
Life cycle costing is a method to determine the entire cost over a product’s intended life cycle.
For buildings, the main factors considered are initial cost, operating costs, and
maintenance/repair costs. LCC is an economic assessment, but it can involve detailed energy
modeling of the structure. LCC does not include environmental impacts of the building and is
not currently included in any of the green building certification systems. The main use for LCC
is as a purchasing tool for predicting the expected costs of a structure, rather than focusing only
on the initial construction costs. For instance, a building with low initial construction costs may
require more maintenance or higher operating costs, wheras a building with a higher initial
construction costs may have lower operating costs. Currently, many groups within the United
6
States government, including the U. S. Forest Service, require all new construction projects to
apply LCC in order to plan for a cost effective structure (USDA 2008).
The U. S. Forest Service has published a document entitled Life-Cycle Cost Analysis for
Buildings is Easier Than You Thought (USDA 2008) to explain the reasoning for LCC and
educate Forest Service personnel on how to conduct an LCC. The simplest form of an LCC is
expressed by Equation 1, where the life cycle cost of the building is composed of the initial cost
(I) plus the replacement cost (Repl) minus the residual sale of the building at the end of its
service life (Res) plus the service life (L) times the cost of operations, maintenance and repair
(OM&R) expressed on a yearly basis.
LCC = I + Repl – Res + L(OM&R)
(1)
Equation 1 represents the simplest form of an LCC. While the equation looks simple, estimating
many of these parameters can become very complex and is subject to the real estate market,
which has demonstrated great volatility in the last several years. Many assumptions about future
economic trends including inflation, depreciation rate, interest rates and energy prices must be
made. The operations, maintenance and repair rates of a structure are subject to the geographic
location, construction of the building envelope, amount and type of insulation in the structure, as
well as the type of construction. As described in the LCA section, LCC results are separate and
distinct for specific building needs and locations and are difficult to generalize.
The Forest Service article lists a series of different LCC computer models which incorporate all
or some of the conditions described above to help produce values to estimate the LCC value of a
building. Most of the models include assumptions on the economy as well as conduct a
relatively detailed energy analysis of the building. More complex LCC models tend to yield
more accurate results; however, the accuracy of the data and predictions used will ultimately
govern the accuracy of the LCC cost results.
2.0 Goals and Objectives
The goal of this project is to develop LCA and LCC tools with examples to account for the
sustainable attributes of post-frame construction. Currently, there is a lack of knowledge among
post-frame professionals as to how to account for the sustainable attributes of their building
methods. Detailed explanations of LCA and LCC concepts can help demonstrate ways to
include the sustainable attributes of post-frame buildings. These tools and examples can help the
PFMI substantiate sustainability and green building claims to establish a market advantage and
also help individual companies establish credits for the various green building certification
systems. Three objectives will be fulfilled to meet this goal.
1. Develop LCA procedures for assessing post-frame building systems as well as similar
systems using wood or steel elements.
2. Explore LCC models for use with post-frame building systems.
7
3. Develop a set of LCA examples using three different post-frame buildings to serve as
examples for the LCA tools and a practice exercise for future LCA use.
3.0 Methods and Results
3.1 Objective 1: LCA Models for Post-frame
A variety of LCA programs were initially surveyed. To create a simplified LCA template for the
software, the type of construction must be known. Construction types included steel and
concrete systems, as well as conventional wood frame systems with options for wood trusses,
wood composites and wood I-joist members. However, NO LCA PROGRAM INCLUDED A
CONSTRUCTION TYPE OF POST-FRAME. After consultation with technical experts, an
equivalent post-frame construction was created through modifications to a structure using the
conventional wood frame assumptions. This is an approximate method subject to the
assumptions of the particular LCA program as well as the validity of assumptions used to
convert the post-frame structure, which are explained in this report.
The Impact Estimator for Buildings from the ATHENA Institute, published by MorrisonHershfield, was chosen for performing the LCA modeling. This program is a comprehensive
LCA tool based on data from the U. S. Life-Cycle Inventory Database, maintained by the
National Renewable Energy Laboratory (www.nrel.gov/lci/database). The program is relatively
inexpensive ($750 for a commercial single-use license per year) and produces a number of
graphical and tabular results, as well as the option to compare up to five different buildings at
once. The program can be obtained on a free 30-day trial basis with limited functionality
(http://athenasmi.org/tools/impactEstimator/) and a user’s manual is available at the website
http://athenasmi.org/tools/impactEstimator/tutorial.html. This report explains some of the basic
functions and outputs of the Impact Estimator for Buildings, but it is recommended that anyone
intending to conduct an LCA first become familiar with the software before use.
The Impact Estimator for Buildings contains an interface with a dropdown menu listing the
sections of a building (Foundation, Walls, Mixed Columns and Beams, Roofs, Floors, Extra
Basic Materials). The program contains a library of construction types and elements associated
with these sections. The ‘Extra Basic Materials’ section allows the addition (or subtraction) of
various construction materials. This ‘Extra Materials’ section is crucial to create an equivalent
conventional construction LCA for post-frame construction. While it seems tempting to total the
amount of material present in the structure and only use the ‘Extra Materials’ section, there are
advantages to including the assemblies, so some functionality of the building elements should
remain, especially with respect to insulation, windows, doors and cladding of the building.
8
3.1.1 Conventional Construction Equivalency Concept
Figure 1 shows the diagram of how the equivalent conventional construction was created based
on the post frame structure. First, the dimensions of the post-frame structure are cataloged.
Then, the spreadsheet is used to create the equivalent wall and roofs conventional wood frame
structures which mimic the post-frame building. Any remaining addition or subtraction of
materials was accounted for by using the ‘Extra Basic Materials’ category. The structure could
then be used in the Impact Estimator for Buildings program.
Post Frame Structure
Spreadsheet to Create Equivalent Conventional
Wood Structure
Walls
Roofs
Extra Basic
Materials
Impact Estimator for
Buildings LCA Program
Figure 1: Diagram of the Process to Conduct an LCA of a Post-Frame Building Using the
Impact Estimator for Buildings
To create an LCA of a post-frame structure, an equivalent conventional framed wood structure
was used as the base. By assuming a conventional structure, which is included in the Impact
Estimator for Buildings library of construction types, building envelope characteristics including
insulation, cladding, windows and doors can be added appropriately. To approximate the postframe structure, a 2x6 stud wall spaced 16 inches on center was used. The 6 inch nominal cavity
is the minimum depth of the wall cavity associated with post-frame construction. This size and
spacing was also chosen to reduce the differences in Extra Basic Materials required by the
structure, which should help to reduce any potential for error by using this approximation.
The other difference between post-frame structures and the Impact Estimator for Buildings was
in the roof section. The LCA program automatically assumes that all roofs have a layer of wood
sheathing (either plywood or OSB). Since some post-frame structures use only steel cladding as
the diaphragm for the roof, a set of calculations were created to remove the sheathing material
from the roof section. Also, roof trusses were assumed to be spaced 2 feet on center.
9
Equation 2 shows the basic equality used to develop the post-frame structure in the Impact
Estimator for Buildings program. The post-frame volume of lumber was approximated by the
2x6 Equivalent Wall, and the use of the Extra Basic Materials category to add/subtract materials.
{Post Frame Volume} = {Conventional Construction} ± {Extra Basic Materials}
(2)
A spreadsheet was created to calculate the post-frame volume of materials, the volume of the 2x6
Equivalent Wall, removal of the roof sheathing, and a summary of all the quantities of Extra
Basic Materials to be added to the Impact Estimator for Buildings program. The following
sections detail the calculation procedures for determining the volume of wood materials in a
typical post-frame wall section, a 2x6 wall section, roof sheathing and truss modifications.
3.1.2 Calculation of Post-frame Wall Volume
Figure 2 shows the elements considered in the post-frame wall. While the post is considered as a
single unit, the length terms are divided into the length above and below the floor surface. If a
concrete pier system or stem wall is used, the length of post below ground can be eliminated or
modified and the extra concrete is added in the ‘Extra Concrete’ category for the wall. The postframe structure includes a skirtboard at the bottom, a fascia board at the top, girts placed on one
or both sides of the post and fireblocking. Fireblocking is placed between the outside edge of the
post and girts to create a continuous barrier between wall cavities. All members except the post
are assumed to be 2x nominal with options to modify the member depth.
Figure 2: Definition of Terms Associated with Post-frame Walls in Model
10
Equations 3 to 10 show the calculation of the wood material for each of the elements described
above. These equations do not contain any unit conversions, but the input basis for all solid
wood materials into the Impact Estimator for Buildings is thousand board feet (Mbf).


VPost = b p d p (H + H e )1 + L 
S
p 

(3)
VSkirtboard = 1.5d sk L
(4)
V Fascia = 1.5d f L
(5)
V ExGirts = 1.5d girt L H
− 1
 Sg 
(6)
VIntGirts = 1.5d girt L H
+ 1
Sg


(7)





VFireblocking =  L + 11.5d fire  H − d sk − d f − d g  H − 1 
S
S
p
g





(8)
VWoodSupportPad = 3d sup Lsup N p
(9)
VConcPad =
πDc2
4
Hc N p
(10)
Where
bp =width of post (in)
dp = depth of post (in)
H = story height of post (above floor) (ft)
SP = spacing of posts (ft)
L = length of wall section considered (ft)
df = depth of fascia (in)
dsk = depth of skirtboard (in)
dg = depth of girt (in)
dfire = depth of fireblocking (in)
Dc = diameter of concrete pad (in)
dsup = depth of cleat at concrete pad (in)
Lsup = length of cleat at concrete pad (in)
Hc = height of concrete pad (in)
Sg = spacing of girts (ft)
Np = number of posts
He = embedded depth of post (concrete pad to top of foundation or floor) (ft)
11
3.1.3 Calculation of 2x6 Equivalent Wall Volume
Figure 3 shows the side view of a typical 2x wall section. All walls were composed of 2x
material with a single bottom plate and double top plate. One row of fireblocking consisting of
similar 2x material as the other wall elements was assumed. Equations 11 to 13 show the
calculation of the volume of wall studs, top and bottom plate and fire blocking. Equation 10
assumes that the studs are doubled at either end of a wall. The fireblocking accounts for only the
blocking in between the spaces of the studs in the wall. These equations do not show any
conversions, but the standard input unit is thousand board feet (Mbf).
Figure 3: General Model of 2x Wall Section Used for Post-frame Equivalence
[( S )+ 3])
(
Vstuds = bd H − 3b) L
(11)
V plates = 3bdL
(12)
[ (
)]
V fireblocking = L − 1 + L b bh
S
(13)
Where
b = width of stud (assumed to be 2 inches nominal (1.5 inches actual) (in)
d = depth of stud (in)
H = total height of wall (story height) (ft)
L = length of wall (ft)
S = spacing of studs (ft)
12
The equivalent wall used for the post-frame approximation is a 2x6 wall with studs spaced 16
inches on center. This wall contains 0.096551 Mbf of lumber per 10 foot long by 10 foot high
section. The change in lumber volume between the 2x6 wall and the post-frame wall was added
to the ‘Extra Basic Materials’ section as a negative or positive value, as appropriate.
3.1.4 Roof Calculations
The Impact Estimator for Buildings Roof category contains an option for ‘Light Frame Wood
Truss.’ The user can select either a parallel or pitched chord truss. This option automatically
assigns a layer of sheathing, either plywood or OSB, to the roofing system. This layer of
sheathing is equal to the square footage of the roof section defined (roof width and truss span
inputed for the roof section). Investigation using the bill of materials function found that the size
of sheathing was directly proportional to the size of the roof and could be removed entirely. For
simplicity, the ½” OSB category was used when the OSB was removed. This modification for
the roof is for a metal sheathed roof ONLY.
Light frame wood roof trusses are typically spaced 2 feet on center. However, roof truss spacing
in post-frame roof systems can vary up to 8 feet on center. The difference in wood material for
these different truss configurations must be estimated. Investigation of the bill of materials
function demonstrated that the amount of small dimension lumber (in Mbf) for the roofs is
calculated as a function of the width of the roof and span of the truss. An estimation of wood
weight in a truss is given in Equation 14 if the span of the truss (Lt) and spacing(T) are known.
Using Equation 14, an adjustment for the volume of lumber in the truss lumber from a standard
spacing (S=2 feet) to a new spacing (T) can be calculated in Equation 15. The constant term
assumes wood materials have a specific gravity of 0.5 for the conversion of weight to volume.
All volumes are given in thousand board feet (Mbf). This modification for the roof is only
needed if the truss spacing is different than 2 feet on center.
L 
DLtruss = 1 + 0.1 t 
T 
(14)
Vdiff truss

 Lt
 1 + 0.1
 Lt Lr  
T
=


 583.3564   1 + 0.1 Lt


S

 
 
  − 1
 
  
 
(15)
L

V purlins = bdLr  t + 1
P

(16)
13
Where
Lt = length of truss (ft)
Lr = width of roof (ft)
T = truss spacing (ft)
S = standard truss spacing (2 feet) (ft)
P = purlin spacing (ft)
3.1.3 Spreadsheet Details
The “LCA Tool for Post-frame Buildings” spreadsheet includes five pages to convert the postframe structure into the equivalent conventional construction which can be assessed by the
Impact Estimator for Buildings. The first page is a title page containing the project name,
designer name, overall square footage, a disclaimer, and all assumptions made to produce these
calculations. The spreadsheet is capable of calculating 8 walls, 4 walls with no equivalent, and 4
roofs. For data security, the spreadsheet formulas have been protected while the input cells can
be changed. The spreadsheet can be used for different projects, including changes in the wall
and roof sizes, but the underlying formula cells cannot be changed. If more wall and roof
sections are needed, a second spreadsheet is needed and the post-frame professional will have to
manually tabulate the Extra Basic Material values. Assumptions include:
•
•
•
•
•
•
•
The basic structure considers 8 walls, 4 walls with no equivalent, and 4 roof sections.
All fireblocking, fascia, girts, embedded cleats and skirtboards are assumed to be 2x
nominal material (1.5 in. thick).
Floor elements are not discussed. Typical wood and concrete pad floor choices are
available and do not need modification.
Equivalent wall has a double top chord (2-2x6).
Skirtboards are single sided.
16d nails are used for laminated posts.
PPT lumber is assumed to have the LCI data as untreated lumber.
The next three pages of the spreadsheet contain the inputs, calculations and outputs per element.
The ‘Wall’ page is used for post-frame walls which will be converted to conventional 2x6 walls.
This page calculates both the post-frame volume (Equations 3 to 10) as well as the 2x6
equivalent wall volume (Equations 11 to 13). The difference between these volumes is found for
the ‘Extra Basic Materials’ section. Figure 4 shows a single wall from the ‘Wall’ spreadsheet.
14
Figure 4. One Wall from the ‘Wall’ Spreadsheet
Figure 5 shows a wall from the ‘Wall No Eq.’ spreadsheet. The ‘Wall No Eq.’ is for post-frame
walls which will not be converted into equivalent 2x6 walls. Figure 5 is identical to Figure 4
execpt for the removal of the 2x6 equivalent wall. All post-frame wall volumes (Equations 3 to
10) were found for the ‘Extra Basic Materials’ section. Examples of these types of walls include
a row of exterior or interior posts which do not need cladding, insulation or other features.
15
Figure 5. One Wall from the ‘Wall No Eq.’ Spreadsheet
Figure 6 shows a roof from the ‘Roof’ spreadsheet. The ‘Roof’ page is used only for substituting
a post-frame metal sheathed roof for the ½” OSB sheathing (Equation 15) and modifying the
spacing of trusses from 2 feet on center (Equation 16).
Figure 6. One Roof from the ‘Roof’ Spreadsheet
The last page ‘Output Summary’ summarizes all of the ‘Extra Basic Materials’ values needed for
the Impact Estimator for Buildings and were shown in order for each material (Wood, Concrete,
Steel). This page also has a reminder of the conventional wall and roof sections which should be
used.
16
3.2 Objective 2: LCC Models for Post Frame
The majority of LCC models available use the same basic programming, called DOE-2.
Differences in the LCC models include the inputs and graphical interface. LCC models usually
consist of more energy-based calculations over the life of the structure, requiring more detailed
inputs than the LCA models which include more product data and construction information.
Hence, most of the LCC models do not have the flexibility present in the LCA models.
The LCC model chosen for this project was eQUEST (http://www.doe2.com/). This program is a
popular format and provides good graphical input and output functions. However, there is NO
SPECIFIC OPTION for post-frame construction within any LCC program. There is an option
for “Wood Frame, Advanced”, but the term is not explained well. While the Excel spreadsheet
developed for the LCA model can help alleviate the problem with the absence of post-frame
construction as an option in the Impact Estimator for Buildings, the complexity of the energy
modeling of the eQUEST program does not allow similar modifications.
The use of LCC seems to be limited for enhancing the post-frame market value in green
building. LCC would most likely be used by an owner / buyer to compare building costs, but is
not as useful to a builder or designer. It is important to establish procedures for post-frame
construction if an LCC is needed. However, the degree of economic analysis and energy
analysis for the building system are beyond the scope of this project.
3.3 Objective 3: LCA Building Examples
Plans for three different post-frame structures were obtained from Dwayne Borkholder. These
plans were slightly modified to produce the three examples discussed below. This section will
provide details about the use of the spreadsheet to convert the post-frame portion of the projects
into a format for the LCA calculation. All other elements of the building (walls, roofs, floors,
foundations, etc.) which are included in the Impact Estimator for Buildings program are not fully
discussed here and several estimations of their quantities (such as the interior wall areas) have
been made to simplify the examples. Zipped files for the three example buildings in the Impact
Estimator for Buildings format (.AT4 extension) can be found at the following link.
Alternatively, type
http://www.postframeadvantage.com/elements/uploads/fckeditor/file/ImpactEstimatorforBuildin
gsdatafiles.zip into an internet browser to Again, any post-frame professionals wishing to
conduct an LCA should be familiar with the general workings of the program before using the
spreadsheet. The following sections provide a short description of each building and then a
discussion of the LCA results. The files created are accessible for use as examples in conducting
an LCA and listed in the ‘6.0 Attachments’ section at the end of this report.
3.3.1 Building #1 Description: Open Sided Machine Shed
17
Building #1 is shown in Figures 7 and 8. It is a 60 foot wide by 144 foot long rectangular
building. Three of the walls (two 60 foot endwalls and one sidewall) have posts spaced 8 feet on
center with a typical wall detail shown in Figure 8a. Posts are 5x6 nail laminated at 8 feet on
center with a 2x8 skirtboard, 2x4 exterior girts spaced 2 feet on center, and a 2x6 fascia board.
All posts were embedded 3.5 feet in the ground and sit upon concrete pads 20 inches in diameter
and 8 inches deep. Two 2x6 cleats are attached to the bottom of each post. For simplicity, the
length of the cleat was assumed equal to the 20 inch diameter concrete pad. The roof system is a
series of trusses spaced 8 feet on center with purlins oriented on edge and spaced 2 feet on center
supporting a corrugated metal roof.
Figure 7: Plan View of Building #1
The fourth wall is shown in Figure 8b and is a double 5x6 nail laminated posts covered with two
2x10s and two 2x12s for an actual dimension of 12 by 8.5 inches spaced 24 feet on center.
There is no skirtboard, girts or fascia. The top of the posts are connected to a boxed header beam
consisting of 2-1.5”x24” LVL sides with 2x6 members at the top and bottom.
18
(a)
(b)
Figure 8: Typical Wall Sections of Building #1: (a) Wall 1 and 2, (b) Wall 3
Table 2 shows the inputs and values calculated for the walls of Building #1. This table follows
the format of the ‘Wall’ spreadsheet input values in Figure 4. Wall#2 includes both endwalls
together for a total length of 120 feet. Wall #2 had posts extending from the ground to the
roofline, so the roof mean height was used for all posts within this wall. Wall #3 has an
additional amount of wood which represents the LVL box beam over the posts in Figure 8b.
Table 2: Input Values for Building #1 Walls
Items
Wall # 1
Length of Wall
144 ft
Height of Wall
Spacing of Posts
Width of Post
Depth of Post
Embedment Depth of Post
16.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Nail
Laminated
(3-2x6)
5 nails /ft
7.25 in
5.5 in
Exterior
3.5 in
3.5 in
2 ft
N/A
5.5 in
20 in
Type of Post
Nail Density Per Foot
Depth of Skirtboard
Depth of Fascia
Girts Exterior or Double Sided ?
Depth of Girt
Depth of Girts
Spacing of Girts
Depth of Fireblocking
Depth of Embedded Cleat
Length of Cleat
Wall #2 – Both
Endwalls
120 ft ( 2 60 foot
walls)
21.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Nail Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Exterior
3.5 in
3.5 in
2 ft
N/A
5.5 in
20 in
Wall #3 – Open Wall
144 ft
14.333 ft
24 ft
8.5 in
12 in
3.5 ft
Nail Laminated
(3-2x6 surrounding
2x10 and 2x12)
5 nails/ft
N/A
N/A
N/A
N/A
N/A
N/A
N/A
5.5 in
20 in
19
Diameter of Concrete Pad
Height of Concrete Pad
20 in
8 in
20 in
8 in
20 in
8 in
Table 3 shows the calculated wall volume for the three walls in Building #1. This table follows
the format of the calculated values in Figure 3 and 4. Notice that Wall 3 does not have an
equivalent 2x6 section since Wall 3 used the ‘Wall No Eq.’ spreadsheet.
20
Table 3: Calculated Values for Wall Volume of Building #1
Items
Wall # 1
Volume of Posts
Volume of Skirtboard
Volume of Fascia
Volume Girts
Volume Cleat
Embedded
Volume of fireblocking
Volume of Additional
Wood Material
Volumeof Equivalent
Stud Wall
1
Wall #3 – Open Wall
0.777206 Mbf
0.1305 Mbf
0.099 Mbf
0.441 Mbf
0.043542 Mbf
Wall #2 – Both
Endwalls
0.819489 Mbf
0.10875 Mbf
0.0825 Mbf
0.4725 Mbf
0.036667 Mbf
0 Mbf
0 Mbf
0 Mbf
0 Mbf
0 Mbf
1.135 Mbf
1.604428 Mbf
1.662182 Mbf
N/A1
1.061064 Mbf
0 Mbf
0 Mbf
0 Mbf
0.016042 Mbf
Wall 3 was calculated using the ‘Wall No Eq.’ Sheet, so no 2x6 wall was considered.
Table 4 shows the values for the ‘Extra Basic Materials’ category for the three walls of Building
#1 from the spreadsheet. The negative values for softwood lumber from Walls #1 and #2
showed that these wall sections has less lumber than a 2x6 equivalent section. Table 4 also
contains large dimension lumber and glulam values if these materials were used for posts, as well
as the concrete and nails for the nail laminated posts. The nails used in the equivalent 2x6 wall
are assumed to be consistent with the nailing of girts, skirt and fascia boards.
Table 4: ‘Extra Basic Materials’ Inputs for Walls from Building #1
Items
Wall # 1
Wall #3 – Open Wall
-0.11318 Mbf
Wall #2 – Both
Endwalls
-0.142276 Mbf
Softwood Lumber,
Small Dimension, kiln
dried
Glulam Beams
Softwood Lumber,
Large Dimension, green
3000 psi Concrete,
Average flyash
Nails
0 ft3
0 Mbf
0 ft3
0 Mbf
0 ft3
0 Mbf
0.96963 yd3
0.80802 yd3
0.323209 yd3
0.044999 tons
0.048979 tons
0.024863 tons
2.2122545 Mbf
Table 5 shows the calculations for the roof of Building #1. The Impact Estimator for Buildings
limits the length of a truss span to 48 feet, so this particular roof must be inputed as two
segments each 30 feet wide. From investigating the bill of materials option, separating the roof
into multiple segments does not change the program output. The changes in truss spacing and
elimination of the OSB from the roof lead to negative lumber values in the ‘Extra Basic
Materials’ for the roof section.
21
Table 5: Roof Volume Calculations from the ‘Roof’ Spreadsheet
Roof Inputs
Truss Span
60 ft
Length of Building
144 ft
Truss Spacing
8 feet on center
Purlin Spacing
2 feet on center
Roof Outputs – Extra Materials Section
Softwood Lumber, Small Dimension,
-6.880652 Mbf
Kiln Dried
-11.5049 msf (3/8”
Oriented Strand Board
basis)
Table 6 presents the ‘Extra Basic Materials’ for Building #1. With the reductions in truss
material and wall posts, there is an overall reduction in the amount of wood used in Building #1
compared to the conventional construction which was assumed for Walls #1,#2 and the roof.
The negative OSB was from the removal of material covering the roof section. Additional nails
were included for the nail laminated posts.
Table 6: Extra Basic Materials from the Spreadsheet for Building #1
Material
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average flyash
Nails
Quantity
-4.92356 Mbf
-11.5049 msf, 38” basis
0 ft3
0 Mbf
2.100859 yd3
0.11842 tons
3.3.2 Building #1 LCA Results
The attachment section contains the Impact Estimator for Buildings file for ‘Building #1’. This
building used only the three walls and roof mentioned in the previous section and was the
simplest example of a post-frame building in these LCA examples. Figures 9, 10, 11 and 12
show some of the outputs from the program. Figure 9 is the bill of materials. This function is
helpful to confirm that all LCA inputs have all been accounted for, and to check if materials were
removed correctly.
22
Figure 9: Bill of Materials Report for Building #1 from the Impact Estimator for Buildings
Figure 10 shows the fossil fuel consumption for the building. Note that operation energy was
NOT considered in these examples and can be added depending on the particular building energy
use. Building #1 would probably have very little operational energy possibly including lighting
and basic equipment depending upon the building function. The primary energy consumption is
broken into life cycle stages of the building (manufacturing, construction, maintenance,
operating energy, end-of-life).
Figure 10: Fossil Fuel Consumption for Building #1 from the Impact Estimator for Buildings
Figure 11 shows the global warming potential and Figure 12 shows the weighted resource use.
Note that the greatest marker in the graph for all three indicators is the manufacturing and
23
maintenance processes. This is true of most wood products that require little energy for
construction or end of life.
Figure 11: Global Warming Potential for Building #1 from the Impact Estimator for Buildings
Figure 12: Weighted Resource Use for Building #1 from the Impact Estimator for Buildings
Figures 10, 11 and 12 show only three of the environmental indicators reported by the Impact
Estimator for Buildings program. These three were selected to show the general trends related to
environmental indicators for the different life cycle phases of the building. Table7 shows the
values of all of the environmental indicators produced by the Impact Estimator for Buildings.
These values are separated by life cycle stage, but can also be displayed in other formats.
24
Table 7: Total Environmental Indicators for Building #1 for Each Life Cycle Stage and Total
(Note: Operational Energy Not Considered)
Environmental Indicator
Primary Energy
Consumption (MJ)
Weighted Resource Use (kg)
Global Warming Potential
(kg CO2 eq)
Acidification Potential
(moles of H+ eq)
HH Respiratory Effects
Potential (kg PM2.5 eq)
Eutrophication Potential
(kg N eq)
Ozone Depletion Potential
(kg CFC-11 eq)
Smog Potential (kg NOx eq)
Manufacturing
Construction
Maintenance
End-of-Life
Total
897643
30025
113721
8173
1049562
123962
1641
5622
172.6
131397.6
58121
1943
2308
478
62850
21218
780.6
1217
26.9
23243
121.5
3.13
7.82
0.0258
132.5
21.1
0.142
0.202
0.0186
21.5
1.79E-04
1.68E-09
1.18E-06
2.15E-08
1.80E-4
94.7
3.35
151.1
0.351
249.5
3.3.3 Building #2 Description: Residential Home
Building #2 was a 3,712 square foot residential structure. The building area measures 80 feet
long by 32 feet wide. Figure 13 shows an overview of the building with all of the walls defined.
The leftmost portion of the building measuring 32 feet long by 32 feet wide is a garage. The
middle section (Walls C) is a two story section that rises above the other portions. The 24 foot
long by 32 foot wide section on the right hand side is a single story portion with the roof
extending to Wall F, which is a row of posts. Wall G is another row of posts where the right and
middle section first story roofs are supported for a front porch. The house contains a foundation
under the 80 foot by 32 foot section and a second floor of 24 feet wide by 32 feet long.
Figure 13: Overview of Walls for Building #2
25
Figure 14 shows the roof overlayed onto the walls from Figure 13. The roofs along the main
building had a 2 foot overhang, and a smaller overhang on the front and back porch roofs. The
second story walls are conventional framing of 2x4 studs 16 inches on center and 7 feet high.
Figure 14: Plan View of Roofs for Building #2
This building used only the wall modification, since the roof was covered with OSB and metal
sheathing with trusses spaced 2 feet on center. Walls A, B, C, D and E used the ‘Wall’
spreadsheet, while Walls F and G used the ‘Wall No Eq.’ spreadsheet. Table 8 shows the
dimensions of each of the post-frame walls. Walls were covered with 30 gauge steel siding,
unfaced fiberglass batt insulation (6 inches thick, R-19), and Type X drywall. Additional wood
materials for some walls include additional fascia boards and a 2x6 at the top of the inside wall
to support the upper edge of the drywall.
Table 9 shows the ‘Extra Basic Materials’ summarized from the post-frame walls in Building #2.
Note that the additional wood materials as well as the double sided girts slightly increased the
wood use versus the equivalent 2x6 walls. The large dimension lumber posts were sued for
Walls F and G.
26
Table 8: Wall Sections in ‘Wall’ and ‘Wall No Eq.’ Spreadsheets for Building #2
Item
Length of Wall
Height of Wall
Spacing of Posts
Width of Post
Depth of Post
Embedment Depth of
Post
Type of Post
Nail Density
Depth of Skirt
Depth of Fascia
Girts Exterior of
Double Sided?
Depth of Girt
Spacing of Girts
Depth of Fireblocking
Depth of Cleat
Length of Cleat
Diameter of Concrete
Pad
Height of Concrete
Pad
Additional Wood
Wall A
32 ft
17 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall B
64 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall C
48 ft
17 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall D
24 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall E
24 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall F
5.5 in
5.5 in
3.5 ft
Wall G
48 ft
8.333 ft
12 ft
5.5 in
5.5 in
3.5 ft
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
6x6 Post
6x6 Post
N/A
0 in
0 in
N/A
N/A
0 in
0 in
N/A
3.5 in
2 ft
1.5 in
N/A
N/A
14 in
3.5 in
2 ft
1.5 in
N/A
N/A
18 in
3.5 in
2 ft
1.5 in
N/A
N/A
24 in
3.5 in
2 ft
1.5 in
N/A
N/A
14 in
3.5 in
2 ft
1.5 in
N/A
N/A
22 in
0 in
N/A
0 in
N/A
N/A
16 in
0 in
N/A
0 in
N/A
N/A
14 in
6 in
8 in
10 in
6 in
10 in
8 in
6 in
0.051 Mbf
0.102 Mbf
0.0765 Mbf
0 Mbf
0.0443 Mbf
0.072 Mbf
0.153 Mbf
Table 9: Extra Basic Materials for Building #2
Item
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average Flyash
Nails
Quantity
1.014153 Mbf
0 msf, 3/8” basis
0 ft3
0.238632 Mbf
1.461983 yd3
0.048163 tons
4.3.4 Building #2 LCA Results
Figure 15 shows the bill of materials for Building #2 and Figures 16, 17 and 18 show the fossil
fuel consumption, global warming potential and weighted resource use environmental indicators
for Building #2. While this building was less than half the size of Building #1, note the
complexity of the residential construction including the foundation, and second story compared
to the machine shed of Building #1.
27
Figure 15: Bill of Materials Report for Building #2 from the Impact Estimator for Buildings
Figure 16: Fossil Fuel Consumption for Building #2 from the Impact Estimator for Buildings
28
Figure 17: Global Warming Potential for Building #2 from the Impact Estimator for Buildings
Figure 18: Weighted Resource Use for Building #2 from the Impact Estimator for Buildings
3.3.5 Building #3 Description: Addition to Church
Building #3 is a 12,912 square foot addition to a church consisting of a lobby and two-story
classroom wing. Figure 19 shows the plan view of the structure outlining the walls which have
post-frame components. All exterior walls were post-frame and used the ‘Wall’ spreadsheet.
The two interior walls, Wall AB and Wall C(e) used the ‘Wall No Eq.’ spreadsheet since these
walls were open. The two story section of the building contains a typical wood framed second
story and a number of interior partition walls, which were included in the Impact Estimator for
Buildings program. The roof system used an asphalt shingle applied over OSB with trusses 2
feet on center, so no modifications were made using the roof spreadsheet. Table 10 shows the
post-frame wall details using the same format as Figure 8 and Tables 2 and 8.
29
(a)
(b)
Figure 19: Plan View of Walls for Building #3, (a) Floor Plan Showing Post-frame Walls, (b)
Side View from the East
Table 10: Wall Sections in ‘Wall’ and ‘Wall No Eq.’ Spreadsheets for Building #3
Item
Length of Wall
Height of Wall
Spacing of Posts
Width of Post
Depth of Post
Embedment Depth of
Post
Type of Post
Nail Density
Depth of Skirt
Depth of Fascia
Girts Exterior of
Double Sided?
Depth of Girt
Spacing of Girts
Depth of Fireblocking
Depth of Cleat
Length of Cleat
Diameter of Concrete
Pad
Height of Concrete
Pad
Additional Wood
Wall Ae
96 ft
22.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall As
64 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall Be
48 ft
17 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall Bs
24 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall Cs
24 ft
10.333 ft
8 ft
4.5 in
5.5 in
3.5 ft
Wall Ce
5.5 in
5.5 in
3.5 ft
Wall AB
48 ft
8.333 ft
12 ft
5.5 in
5.5 in
3.5 ft
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
7.2.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
Nail
Laminated
(3-2x6)
5 nails/ft
7.25 in
5.5 in
Double
6x6 Post
6x6 Post
N/A
0 in
0 in
N/A
N/A
0 in
0 in
N/A
3.5 in
2 ft
1.5 in
N/A
N/A
14 in
3.5 in
2 ft
1.5 in
N/A
N/A
18 in
3.5 in
2 ft
1.5 in
N/A
N/A
24 in
3.5 in
2 ft
1.5 in
N/A
N/A
14 in
3.5 in
2 ft
1.5 in
N/A
N/A
22 in
0 in
N/A
0 in
N/A
N/A
16 in
0 in
N/A
0 in
N/A
N/A
14 in
6 in
8 in
10 in
6 in
10 in
8 in
6 in
0.051 Mbf
0.102 Mbf
0.0765 Mbf
0 Mbf
0.0443 Mbf
0.072 Mbf
0.153 Mbf
Table 11 shows the Extra Basic Materials for Building #3. As in Building #2, the double sided
girts and additional wood material increase the amount of lumber use versus the 2x6 equivalent
wall. Note that these comparisons with the 2x6 wall DO NOT include identical strength
30
elements, only a standardized 2x6 design which may or may not be adequate for the particular
structural requirements.
Table 11: Extra Basic Materials for Building #2
Item
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average Flyash
Nails
Quantity
2.894842 Mbf
0 msf, 3/8” basis
0 ft3
0 Mbf
13.85678 yd3
0.187065 tons
3.3.6 Building #3 LCA Results
Figure 20 shows the bill of materials for Building #3. Again, the complexity of Building #3 is
much greater than the other two buildings due to the size and interior finish. Figures 21, 22, and
23 show the primary energy consumption, global warming potential, and weighted resource use
for each life cycle stage for Building #3. Note the difference in the maintenance values between
Building #3 and the other two buildings. The increase in maintenance materials seems related to
the use of asphalt shingles, while the other two buildings used metal roofing with or without
OSB.
31
Figure 20: Bill of Materials Report for Building #3 from the Impact Estimator for Buildings
Figure 21: Fossil Fuel Consumption for Building #3 from the Impact Estimator for Buildings
32
Figure 22: Global Warming Potential for Building #3 from the Impact Estimator for Buildings
Figure 23: Weighted Resource Use for Building #3 from the Impact Estimator for Buildings
Figure 24 shows a comparison of the global warming potential between Building #3 with asphalt
shingles and with the asphalt shingles removed and metal roofing used instead. Note the large
change in both the manufacturing and maintenance energy for using asphalt shingles. Figure 24
illustrates one of the features of the Impact Estimator for Buildings program to create
comparisons for different building configurations.
33
Figure 24: Comparison of Global Warming Potential for Building #3 and Building #3 With a
Metal Roof
3.3.7 LCA Comparison of Three Buildings
Table 12 shows the total environmental indicators from the three buildings. These values are the
total environmental indicators considering both material and transportation for the
manufacturing, construction, maintenance and end-of-life portions of the building life cycle.
Operation energy was not considered for any of these examples. Building #2 was the smallest
structure in square footage, but did not always have all of the smallest environmental indicators.
Building #1 was better than Building #2 on some indicators due to the simplicity of the structure
(no interior walls, no insulation). These indicators may sometimes be contradictory and require
interpretation to illustrate the use of LCA analysis to compare different building material and
construction options.
Table 12: Total Values for All Environmental Indicators of the Three Buildings
Indicator
Primary Energy Consumption, MJ
Weighted Resource Use, kg
Global Warming Potential, kg CO2 Eq.
Acidification Potential, moles H+ Eq.
Human Health Respiratory Effects Potential,
kg PM2.5 Eq.
Eutrophication Potential, kg N Eq.
Ozone Depletion Potential, kg CFC-11 Eq.
Smog Potential, kg NOX Eq.
Building #1
1.05x106
1.31x105
6.29x104
2.32x104
1.32x102
Building #2
9.38x105
2.23x105
6.12x104
3.18x104
2.48x102
Building #3
9.73x106
1.11x106
4.76x105
2.565x105
1.66x103
2.15x101
1.80x10-4
2.50x102
2.54x101
1.26x10-4
3.24x102
1.38x102
3.54x10-4
2.51x103
34
Figure 25 shows the fossil fuel consumption of the three buildings per life cycle stage. The fossil
fuel consumption for Building #1 is greater than Building #2 due to the increased square footage.
For both Buildings #1 and #2, the majority of the fossil fuel consumption per square meter of the
building is in the manufacturing of the materials since operating costs were not included.
However, for Building #3, a greater energy consumption is in the maintenance of the building
most likely due to the use of asphalt shingles in place of metal cladding.
Figure 25: Comparison of Fossil Fuel Consumption for the Three Buildings Considering Life
Cycle per m2 of Building Area (Operating Costs Not Considered)
Figure 26 shows the global warming potential of the three buildings per life cycle stage. The
trends in Figure 26 are similar to Figure 25, with Building #1 being greater than Building #2 and
both buildings having the majority of the global warming potential in the manufacturing stage.
Building #3 shows a high global warming potential in both the manufacturing and maintenance
phases. For the analysis of these three buildings, the trends in the energy consumption and
global warming potential indicators are similar.
Figure 27 shows the comparison of the weighted resource use indicator for the three buildings
per life cycle stage. Figure 27 shows a different trend than the previous two indicators, with
Building #1 have less resource use than Building #2, which had less resource use than Building
#3. The maintenance resources needed in Building #3 are about one-fourth of the manufacturing
resources.
35
Figure 26: Comparison of Global Warming Potential for the Three Buildings Considering Life
Cycle (Operating Costs Not Considered)
Figure 27: Comparison of Weighted Resource Use for the Three Buildings Considering Life
Cycle (Operating Costs Not Considered)
36
These three environmental indicators give some idea of the type of results which are obtained
from the Impact Estimator for Buildings. Depending on the weighting and importance of the
different indicators, a particular choice for a building can be made. These three buildings
demonstrate the wide range of post-frame structures possible and give a good introduction to the
use of life cycle analysis.
4.0 Conclusions
This project demonstrated the use of LCA and LCC methods related to post-frame construction.
LCA is a tool to measure the environmental inputs and outputs used by a building. Current LCA
software packages do not include post-frame considerations. A spreadsheet demonstrating a way
to create equivalent conventional construction walls and roof while using the extra basic
materials options was created. LCC is a tool for examining the total cost of a structure over its
lifetime. Software packages for LCC again do not include post-frame structures explicitly for
energy modeling and seem too complex to repeat the equivalency created for LCA software.
Three buildings were analyzed using the LCA software and spreadsheet. The example
spreadsheets and the Impact Estimator for Buildings files are useful as training tools for helping
post-frame designers perform LCA to demonstrate the sustainability of their structures.
5.0 References
Trusty, W. B. and S. Horst 2002. Integrating LCA Tools In Green Building Rating Systems.
Published in “The Austin Papers: Best of the 2002 International Green Building Conference”
compiled by Editors of Environmental Building News, BuildingGreen, Inc., p.53-57.
http://www.athenasmi.org/publications/docs/LCA_Tool_Integr_Paper.pdf
Schenck, R. C. 2000. LCA for Mere Mortals: A Primer on Environmental Life Cycle
Assessment. IERE.
USDA. 2008. Life Cycle Cost Analysis for Buildings is Easier Than You Thought. 0873-2839MTDC. USDA Forest Service. Technology and Development Center. Missoula, MT.
37
6.0 Attachments
Excel Spreadsheet “LCA Tool for Post-frame Buildings” This is the Excel Spreadsheet referred
to in the report. The formula cells have been locked to protect the integrity of the project.
PDF Files
“Building 1 Machine Shed.pdf” pdf of spreadsheet for Building #1
“Building 2 Home.pdf” pdf of spreadsheet for Building #2
“Building 3 Addition to Church.pdf” pdf of spreadsheet for Building #3
Impact Estimator for Buildings Files
“Building #1.AT4”
“Building #2.AT4”
“Building #3.AT4”
38
Preparation Sheet for Post Frame Structures Using
ATHENA Institute's Impact Estimator for Buildings
Written by Daniel Hindman
National Frame Builders Association
Project Name:
Designer:
Square Footage:
Building 1
Hindman
8,640 ft^2
NOTE: This is only a design aid and is not meant to replace engineering decisions
ASSUMPTIONS:
The basic structure considers 8 different walls and 4 roof sections
All fireblocking ,fascia, girts, embedded cleats and skirtboards are assumed to be 2x material (1.5 in thick)
Floor elements are not discussed. Typical wood and concrete pad floor choices are available and do not need modification.
Equivalent wall has a double top chord (2-2x6).
Skirtboards are single sided.
16d nails are used for nail laminated posts.
Title Page
Wall Calculations for Post Frame Conversion
Project:
Building 1
Designer: Hindman
SF:
8,640 ft^2
Wall 1- 144 ft Sidewall
Input the following dimensions of the post frame wall.
L
Length of Wall
144 ft
h
Height of Wall
16.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
5.5 in
Girt?
Are girts (E) exterior or (D) double sided?
E
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
5.5 in
Lc
length of cleat
20 in
Dc
diameter of concrete pad
20 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
0 in
h
depth of beam
0 in
L
length of beam
0 ft
0 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.777206 Mbf
Vs
volume of skirtboard
0.1305 Mbf
Vf
volume fascia
0.099 Mbf
Vg
volume girts
0.441 Mbf
Vc
volume cleat embed
0.043542 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0 Mbf
Equivalent Stud Wall
Vs
volume studs
1.217795 Mbf
Vtc
volume top and bottom chord
0.297 Mbf
Vb
volume blocking
0.089633 Mbf
V 2x4
1.604428 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
-0.11318
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.969627
Nails
0.044999
Mbf
ft^3
Mbf
yd^3
tons
Wall 2 - Two 60 ft Endwalls
Input the following dimensions of the post frame wall.
L
Length of Wall
120 ft
h
Height of Wall
21.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
5.5 in
Girt?
Are girts (E) exterior or (D) double sided?
E
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
5.5 in
Lc
length of cleat
20 in
Dc
diameter of concrete pad
20 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
0 in
h
depth of beam
0 in
L
length of beam
0 ft
0 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.819489 Mbf
Vs
volume of skirtboard
0.10875 Mbf
Vf
volume fascia
0.0825 Mbf
Vg
volume girts
0.4725 Mbf
Vc
volume cleat embed
0.036667 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0 Mbf
Equivalent Stud Wall
Vs
volume studs
1.340002 Mbf
Vtc
volume top and bottom chord
0.2475 Mbf
Vb
volume blocking
0.07468 Mbf
V 2x4
1.662182 Mbf
Wood
Wood
Wood
Concrete
Steel
Walls
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
-0.142276
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.808023
Nails
0.048979
Mbf
ft^3
Mbf
yd^3
tons
Wall Calculations for Post Frame Conversion
Project:
Building 1
Designer: Hindman
SF:
8,640 ft^2
Wall 3 - 144 ft Open Sidewall
Input the following dimensions of the post frame wall.
L
Length of Wall
144 ft
h
Height of Wall
14.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
24 ft
Pb
wdith of post (parallel to wall)
8.5 in
Pd
depth of post (perpendicular to wall)
12 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
N
N
nail density per foot per plane
5 nails
ds
depth of skirt
0 in
dt
depth of fascia
0 in
Girt?
Are girts (E) exterior or (D) double sided?
e
dg
depth of girt
0 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
5.5 in
Lc
length of cleat
20 in
Dc
diameter of concrete pad
20 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
63 in
L
length of beam
144 ft
1.135 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
1.061064 Mbf
Vs
volume of skirtboard
0 Mbf
Vf
volume fascia
0 Mbf
Vg
volume girts
0 Mbf
Vc
volume cleat embed
0.016042 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
1.13544 Mbf
The following values are the extra materials needed for post frame wall
Wood
Softwood Lumber, Small Dimension, kiln dried
2.212545 Mbf
Wood
Glulam Beams
0 ft^3
Wood
Softwood Lumber, Large Dimension, green
0 Mbf
Concrete 3000 psi Concrete, Average flyash
0.323209 yd^3
Steel
Nails
0.024863 tons
Walls No Eq.
Roof Modifications
Follow all recommendations for for inserting roofs.
If you are using a metal roofing, choose the 1/2" OSB option and then insert the negative OSB into the extra materials section
Lt
Ll
T
ps
b
h
L
Va
Vt
Vp
Roof 1
Length of Truss
Length of roof section (perpendicular to trusses)
Type of Roof (S) OSB/Plywood, (M) Sheet Metal
Truss spacing
purlin spacing
Additional Wood Calculator
width of beam
depth of beam
length of beam
additional wood material
volume of truss
volume of purlins
Extra Materials for Roof 1 in Impact Estimator for Buildings
Wood
Softwood Lumber, Small Dimension, kiln dried
Wood
Oriented Strand Board
63.25 ft
144 ft
M
8 ft
2 ft
0
0
0
0
-8.896652
2.016
in
in
ft
Mbf
Mbf
Mbf
-6.880652 Mbf
-11.5049 msf (3/8" basis)
Roof
Modification for the Post Frame portions of Wood Structure (i.e., walls and roofs)
Follow all input commands for the Impact Estimator for Buildings with the Following Additions:
Walls
Exterior walls are Wood Stud Walls
Load Bearing
No Sheathing
16 in o.c. Stud Spacing
Green Lumber
2x6
Roof
Wood Truss
1/2" OSB
Extra Materials
Add the following extra materials to convert the walls, roof and concrete pads
Wood
Wood
Wood
Wood
Concrete
Steel
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average flyash
Nails
Output Summary
-4.92356
-11.5049
0
0
2.100859
0.118841
Mbf
msf, 3/8" basis
ft^3
Mbf
yd^3
tons
Preparation Sheet for Post Frame Structures Using
ATHENA Institute's Impact Estimator for Buildings
Written by Daniel Hindman
National Frame Builders Association
Project Name:
Designer:
Square Footage:
Building 2
Hindman
3,712 ft^2
NOTE: This is only a design aid and is not meant to replace engineering decisions
ASSUMPTIONS:
The basic structure considers 8 different walls and 4 roof sections
All fireblocking ,fascia, girts, embedded cleats and skirtboards are assumed to be 2x material (1.5 in thick)
Floor elements are not discussed. Typical wood and concrete pad floor choices are available and do not need modification.
Equivalent wall has a double top chord (2-2x6).
Skirtboards are single sided.
16d nails are used for nail laminated posts.
Title Page
Wall Calculations for Post Frame Conversion
Project:
Building 2
Designer: Hindman
SF:
3,712 ft^2
Wall A
Input the following dimensions of the post frame wall.
L
Length of Wall
32 ft
h
Height of Wall
17 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
5.5 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
14 in
hc
height of concrete pad
6 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
12.75 in
L
length of beam
32 ft
0.051 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.211406 Mbf
Vs
volume of skirtboard
0.029 Mbf
Vf
volume fascia
0.022 Mbf
Vg
volume girts
0.224 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0.013027 Mbf
Va
additional wood
0.051 Mbf
Equivalent Stud Wall
Vs
volume studs
0.308602 Mbf
Vtc
volume top and bottom chord
0.066 Mbf
Vb
volume blocking
0.019852 Mbf
V 2x4
0.394453 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.15598
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.079186
Nails
0.010408
Mbf
ft^3
Mbf
yd^3
tons
Wall B
Input the following dimensions of the post frame wall.
L
Length of Wall
64 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
5.5 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
18 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
12.75 in
L
length of beam
64 ft
0.102 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.256775 Mbf
Vs
volume of skirtboard
0.058 Mbf
Vf
volume fascia
0.044 Mbf
Vg
volume girts
0.28 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0.013675 Mbf
Va
additional wood
0.102 Mbf
Equivalent Stud Wall
Vs
volume studs
0.349152 Mbf
Vtc
volume top and bottom chord
0.132 Mbf
Vb
volume blocking
0.039789 Mbf
V 2x4
0.520941 Mbf
Wood
Wood
Wood
Concrete
Steel
Walls
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.233509
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.349066
Nails
0.012653
Mbf
ft^3
Mbf
yd^3
tons
Wall Calculations for Post Frame Conversion
Project:
Building 2
Designer: Hindman
SF:
3712 ft^2
Wall C
Input the following dimensions of the post frame wall.
L
Length of Wall
48 ft
h
Height of Wall
17 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
5.5 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
24 in
hc
height of concrete pad
10 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
12.75 in
L
length of beam
48 ft
0.0765 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.295969 Mbf
Vs
volume of skirtboard
0.0435 Mbf
Vf
volume fascia
0.033 Mbf
Vg
volume girts
0.336 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0.018238 Mbf
Va
additional wood
0.0765 Mbf
Equivalent Stud Wall
Vs
volume studs
0.445758 Mbf
Vtc
volume top and bottom chord
0.099 Mbf
Vb
volume blocking
0.02982 Mbf
V 2x4
0.574578 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.228629
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.581776
Nails
0.015612
Mbf
ft^3
Mbf
yd^3
tons
Wall D
Input the following dimensions of the post frame wall.
L
Length of Wall
24 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
14 in
hc
height of concrete pad
6 in
Additional Wood Calculator
b
width of beam
0 in
h
depth of beam
0 in
L
length of beam
0 ft
0 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.114122 Mbf
Vs
volume of skirtboard
0.02175 Mbf
Vf
volume fascia
0.02175 Mbf
Vg
volume girts
0.105 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0.005969 Mbf
Va
additional wood
0 Mbf
Equivalent Stud Wall
Vs
volume studs
0.143769 Mbf
Vtc
volume top and bottom chord
0.0495 Mbf
Vb
volume blocking
0.014867 Mbf
V 2x4
0.208136 Mbf
Wood
Wood
Wood
Concrete
Steel
Walls
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.060455
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.05939
Nails
0.004745
Mbf
ft^3
Mbf
yd^3
tons
Wall Calculations for Post Frame Conversion
Project:
Building 2
Designer: Hindman
SF:
3712 ft^2
Wall E
Input the following dimensions of the post frame wall.
L
Length of Wall
24 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
9.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
22 in
hc
height of concrete pad
10 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
14.75 in
L
length of beam
24 ft
0.04425 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.114122 Mbf
Vs
volume of skirtboard
0.02175 Mbf
Vf
volume fascia
0.02775 Mbf
Vg
volume girts
0.105 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0.005844 Mbf
Va
additional wood
0.04425 Mbf
Equivalent Stud Wall
Vs
volume studs
0.143769 Mbf
Vtc
volume top and bottom chord
0.0495 Mbf
Vb
volume blocking
0.014867 Mbf
V 2x4
0.208136 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.11058
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.244427
Nails
0.004745
Mbf
ft^3
Mbf
yd^3
tons
Walls
Wall Calculations for Post Frame Conversion
Project:
Building 2
Designer: Hindman
SF:
3,712 ft^2
Wall F
Input the following dimensions of the post frame wall.
L
Length of Wall
24 ft
h
Height of Wall
8.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
12 ft
Pb
wdith of post (parallel to wall)
5.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
S
N
nail density per foot per plane
5 nails
ds
depth of skirt
0 in
dt
depth of fascia
0 in
Girt?
Are girts (E) exterior or (D) double sided?
e
dg
depth of girt
0 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
16 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
24 in
L
length of beam
24 ft
0.072 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.089487 Mbf
Vs
volume of skirtboard
0 Mbf
Vf
volume fascia
0 Mbf
Vg
volume girts
0 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0.072 Mbf
The following values are the extra materials needed for post frame wall
Wood
Softwood Lumber, Small Dimension, kiln dried
0.072 Mbf
Wood
Glulam Beams
0 ft^3
Wood
Softwood Lumber, Large Dimension, green
0.089487 Mbf
Concrete 3000 psi Concrete, Average flyash
0.068951 yd^3
Steel
Nails
0 tons
Wall G
Input the following dimensions of the post frame wall.
L
Length of Wall
48 ft
h
Height of Wall
8.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
12 ft
Pb
wdith of post (parallel to wall)
5.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
S
N
nail density per foot per plane
5 nails
ds
depth of skirt
0 in
dt
depth of fascia
0 in
Girt?
Are girts (E) exterior or (D) double sided?
e
dg
depth of girt
0 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
0 in
Lc
length of cleat
0 in
Dc
diameter of concrete pad
14 in
hc
height of concrete pad
6 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
25.5 in
L
length of beam
48 ft
0.153 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.149145 Mbf
Vs
volume of skirtboard
0 Mbf
Vf
volume fascia
0 Mbf
Vg
volume girts
0 Mbf
Vc
volume cleat embed
0 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0.153 Mbf
The following values are the extra materials needed for post frame wall
Wood
Softwood Lumber, Small Dimension, kiln dried
0.153 Mbf
Wood
Glulam Beams
0 ft^3
Wood
Softwood Lumber, Large Dimension, green
0.149145 Mbf
Concrete 3000 psi Concrete, Average flyash
0.079186 yd^3
Steel
Nails
0 tons
Walls No Eq.
Modification for the Post Frame portions of Wood Structure (i.e., walls and roofs)
Follow all input commands for the Impact Estimator for Buildings with the Following Additions:
Walls
Exterior walls are Wood Stud Walls
Load Bearing
No Sheathing
16 in o.c. Stud Spacing
Green Lumber
2x6
Roof
Wood Truss
1/2" OSB
Extra Materials
Add the following extra materials to convert the walls, roof and concrete pads
Wood
Wood
Wood
Wood
Concrete
Steel
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average flyash
Nails
Output Summary
1.014153
0
0
0.238632
1.461983
0.048163
Mbf
msf, 3/8" basis
ft^3
Mbf
yd^3
tons
Preparation Sheet for Post Frame Structures Using
ATHENA Institute's Impact Estimator for Buildings
Written by Daniel Hindman
National Frame Builders Association
Project Name:
Designer:
Square Footage:
Building 3
Hindman
12,912 ft^2
NOTE: This is only a design aid and is not meant to replace engineering decisions
ASSUMPTIONS:
The basic structure considers 8 different walls and 4 roof sections
All fireblocking ,fascia, girts, embedded cleats and skirtboards are assumed to be 2x material (1.5 in thick)
Floor elements are not discussed. Typical wood and concrete pad floor choices are available and do not need modification.
Equivalent wall has a double top chord (2-2x6).
Skirtboards are single sided.
16d nails are used for nail laminated posts.
Title Page
Wall Calculations for Post Frame Conversion
Project:
Building 3
Designer: Hindman
SF:
12,912 ft^2
Wall Ae
Input the following dimensions of the post frame wall.
L
Length of Wall
96 ft
h
Height of Wall
22.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
5.5 in
Lc
length of cleat
18 in
Dc
diameter of concrete pad
18 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
32.75 in
L
length of beam
96 ft
0.393 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.692647 Mbf
Vs
volume of skirtboard
0.087 Mbf
Vf
volume fascia
0.087 Mbf
Vg
volume girts
0.924 Mbf
Vc
volume cleat embed
0.026813 Mbf
Vf
volume fireblocking
0.044382 Mbf
Va
additional wood
0.393 Mbf
Equivalent Stud Wall
Vs
volume studs
1.132209 Mbf
Vtc
volume top and bottom chord
0.198 Mbf
Vb
volume blocking
0.059727 Mbf
V 2x4
1.389936 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.565259
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.523599
Nails
0.04102
Mbf
ft^3
Mbf
yd^3
tons
Wall As
Input the following dimensions of the post frame wall.
L
Length of Wall
148 ft
h
Height of Wall
18 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
5.5 in
Lc
length of cleat
38 in
Dc
diameter of concrete pad
38 in
hc
height of concrete pad
16 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
32.75 in
L
length of beam
148 ft
0.605875 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.842531 Mbf
Vs
volume of skirtboard
0.134125 Mbf
Vf
volume fascia
0.134125 Mbf
Vg
volume girts
1.1655 Mbf
Vc
volume cleat embed
0.082729 Mbf
Vf
volume fireblocking
0.051508 Mbf
Va
additional wood
0.605875 Mbf
Equivalent Stud Wall
Vs
volume studs
1.381359 Mbf
Vtc
volume top and bottom chord
0.30525 Mbf
Vb
volume blocking
0.092125 Mbf
V 2x4
1.778734 Mbf
Wood
Wood
Wood
Concrete
Steel
Walls
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
1.001003
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
7.00071
Nails
0.049592
Mbf
ft^3
Mbf
yd^3
tons
Wall Calculations for Post Frame Conversion
Project:
Building 3
Designer: Hindman
SF:
12912 ft^2
Wall Be
Input the following dimensions of the post frame wall.
L
Length of Wall
44 ft
h
Height of Wall
14.167 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
5.5 in
Lc
length of cleat
18 in
Dc
diameter of concrete pad
18 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
10.75 in
L
length of beam
44 ft
0.059125 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.218629 Mbf
Vs
volume of skirtboard
0.039875 Mbf
Vf
volume fascia
0.039875 Mbf
Vg
volume girts
0.2695 Mbf
Vc
volume cleat embed
0.012375 Mbf
Vf
volume fireblocking
0.01261 Mbf
Va
additional wood
0.059125 Mbf
Equivalent Stud Wall
Vs
volume studs
0.341352 Mbf
Vtc
volume top and bottom chord
0.09075 Mbf
Vb
volume blocking
0.027328 Mbf
V 2x4
0.45943 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.033055
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.218166
Nails
0.010842
Mbf
ft^3
Mbf
yd^3
tons
Wall Bs
Input the following dimensions of the post frame wall.
L
Length of Wall
48 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
5.5 in
Lc
length of cleat
18 in
Dc
diameter of concrete pad
18 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
10.75 in
L
length of beam
48 ft
0.0645 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.199714 Mbf
Vs
volume of skirtboard
0.0435 Mbf
Vf
volume fascia
0.0435 Mbf
Vg
volume girts
0.21 Mbf
Vc
volume cleat embed
0.014438 Mbf
Vf
volume fireblocking
0.010445 Mbf
Va
additional wood
0.0645 Mbf
Equivalent Stud Wall
Vs
volume studs
0.266999 Mbf
Vtc
volume top and bottom chord
0.099 Mbf
Vb
volume blocking
0.02982 Mbf
V 2x4
0.395819 Mbf
Wood
Wood
Wood
Concrete
Steel
Walls
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.055063
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
0.261799
Nails
0.009489
Mbf
ft^3
Mbf
yd^3
tons
Wall Calculations for Post Frame Conversion
Project:
Building 3
Designer: Hindman
SF:
12912 ft^2
Wall C(s)
Input the following dimensions of the post frame wall.
L
Length of Wall
88 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
7 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
7.25 in
dt
depth of fascia
7.25 in
Girt?
Are girts (E) exterior or (D) double sided?
D
dg
depth of girt
3.5 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
1.5 in
dc
depth of cleat
5.5 in
Lc
length of cleat
32 in
Dc
diameter of concrete pad
32 in
hc
height of concrete pad
13 in
Additional Wood Calculator
b
width of beam
1.5 in
h
depth of beam
10.75 in
L
length of beam
88 ft
0.11825 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.370897 Mbf
Vs
volume of skirtboard
0.07975 Mbf
Vf
volume fascia
0.07975 Mbf
Vg
volume girts
0.385 Mbf
Vc
volume cleat embed
0.047667 Mbf
Vf
volume fireblocking
0.019398 Mbf
Va
additional wood
0.11825 Mbf
Equivalent Stud Wall
Vs
volume studs
0.472383 Mbf
Vtc
volume top and bottom chord
0.1815 Mbf
Vb
volume blocking
0.054742 Mbf
V 2x4
0.708625 Mbf
Wood
Wood
Wood
Concrete
Steel
Considering a 2x6 stud wall 16 inches on center,
the following values are the extra materials needed
Softwood Lumber, Small Dimension, kiln dried
0.139439
Glulam Beams
0
Softwood Lumber, Large Dimension, green
0
3000 psi Concrete, Average flyash
2.6891
Nails
0.018979
Mbf
ft^3
Mbf
yd^3
tons
Walls
Wall Calculations for Post Frame Conversion
Project:
Building 3
Designer: Hindman
SF:
12,912 ft^2
Wall (AB)
Input the following dimensions of the post frame wall.
L
Length of Wall
120 ft
h
Height of Wall
18 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
0 in
dt
depth of fascia
0 in
Girt?
Are girts (E) exterior or (D) double sided?
e
dg
depth of girt
0 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
5.5 in
Lc
length of cleat
30 in
Dc
diameter of concrete pad
30 in
hc
height of concrete pad
12 in
Additional Wood Calculator
b
width of beam
0 in
h
depth of beam
0 in
L
length of beam
120 ft
0 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.7095 Mbf
Vs
volume of skirtboard
0 Mbf
Vf
volume fascia
0 Mbf
Vg
volume girts
0 Mbf
Vc
volume cleat embed
0.055 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0 Mbf
The following values are the extra materials needed for post frame wall
Wood
Softwood Lumber, Small Dimension, kiln dried
0.7645 Mbf
Wood
Glulam Beams
0 ft^3
Wood
Softwood Lumber, Large Dimension, green
0 Mbf
Concrete 3000 psi Concrete, Average flyash
2.727077 yd^3
Steel
Nails
0.041327 tons
Wall C(e)
Input the following dimensions of the post frame wall.
L
Length of Wall
84 ft
h
Height of Wall
10.333 ft
(For sidewall, use height of wall; for endwall, use mean roof height)
Sp
Spacing of posts (center-to-center)
8 ft
Pb
wdith of post (parallel to wall)
4.5 in
Pd
depth of post (perpendicular to wall)
5.5 in
E
embedment depth of post
3.5 ft
Post?
Solid (S), Naillam (N), Glulam (G)
n
N
nail density per foot per plane
5 nails
ds
depth of skirt
0 in
dt
depth of fascia
0 in
Girt?
Are girts (E) exterior or (D) double sided?
e
dg
depth of girt
0 in
sg
spacing of girts (center-to-center)
2 ft
df
depth of fireblocking
0 in
dc
depth of cleat
5.5 in
Lc
length of cleat
18 in
Dc
diameter of concrete pad
18 in
hc
height of concrete pad
8 in
Additional Wood Calculator
b
width of beam
0 in
h
depth of beam
0 in
L
length of beam
84 ft
0 Mbf
These cells perform the calculation of wood volume in the wall.
Vp
volume of posts
0.313836 Mbf
Vs
volume of skirtboard
0 Mbf
Vf
volume fascia
0 Mbf
Vg
volume girts
0 Mbf
Vc
volume cleat embed
0.022688 Mbf
Vf
volume fireblocking
0 Mbf
Va
additional wood
0 Mbf
The following values are the extra materials needed for post frame wall
Wood
Softwood Lumber, Small Dimension, kiln dried
0.336524 Mbf
Wood
Glulam Beams
0 ft^3
Wood
Softwood Lumber, Large Dimension, green
0 Mbf
Concrete 3000 psi Concrete, Average flyash
0.436332 yd^3
Steel
Nails
0.015816 tons
Walls No Eq.
Modification for the Post Frame portions of Wood Structure (i.e., walls and roofs)
Follow all input commands for the Impact Estimator for Buildings with the Following Additions:
Walls
Exterior walls are Wood Stud Walls
Load Bearing
No Sheathing
16 in o.c. Stud Spacing
Green Lumber
2x6
Roof
Wood Truss
1/2" OSB
Extra Materials
Add the following extra materials to convert the walls, roof and concrete pads
Wood
Wood
Wood
Wood
Concrete
Steel
Softwood Lumber, Small Dimension, kiln dried
Oriented Strand Board
Glulam Beams
Softwood Lumber, Large Dimension, green
3000 psi Concrete, Average flyash
Nails
Output Summary
2.894842
0
0
0
13.85678
0.187065
Mbf
msf, 3/8" basis
ft^3
Mbf
yd^3
tons