SETTING POSTS AND INSTALLING FOOTINGS AND FOUNDATIONS
Products highlighted in this section:
SAKRETE
®
High Strength
SAKRETE
®
Fast Setting
Ultra-High
Strength
Concrete
Mix
One of the easiest do-it yourself projects
around is the anchoring of a post or pole. It’s
one of the first projects a homeowner usually
attempts using a concrete mix.
Setting Posts
A sampling of projects include:
• Mail boxes
• Lamp posts
• Basketball backboard posts
• Fences
• Swing sets
• Clothes line poles
• Birdhouses
• Garden lights
• Flower trellis
Steps Include:
Use a post hole digger to prepare the hole.
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Take care not to disturb underground power
or telephone cable. Many municipalities will
locate underground power lines free of
charge. “Think safety.” Place 2 – 3 inches of
gravel in the bottom of the hole.
while the concrete sets. For instance, a
basketball post may require bracing while a
mailbox post will not.
There are many consumers who want to
save time and efforts without sacrificing
results. That is why SAKRETE® Fast Setting
Ultra-High Strength Concrete Mix was
formulated. It will set posts without mixing.
Simply dig a hole to the specified depth, fill
the hole1/3 full of water, center the post, fill
with SAKRETE® Fast Setting Ultra-High
Strength Concrete Mix, which sets in
approximately 30 minutes and is hard in
approximately 8 hours. Tamp the top of the
hole and that’s it.
Mix SAKRETE® High Strength Concrete
Mix according to package instruction.
Place the post in the center of the hole. For
large heavy posts, bracing may be required
SAKRETE® Concrete Mix
Estimating Guide
POST ESTIMATING GUIDE
Number of bags requires assuming a 10 inch
(0.25 m) diameter hole
Use a level to check placement.
Fill the hole with the SAKRETE® High
Strength Concrete Mix, creating a mound
that will prevent the collection of water.
40 lb.
12 in.
(.3m)
50 lb.
1.8
1.4
2.7
2.2
24 in.
(.6m)
3.6
2.9
30 in.
(.76m)
4.5
3.6
60 lb.
1.2
1.8
2.4
3.0
90 lb.
0.8
1.2
1.6
2.0
80 lb.
1.0
COVERAGE
1.4
1.8
2.3
Bag Size
Yield
50 lb. (22.7 kg)
0.38 cu ft. (.010 cu. m)
40 lb. (18.1 kg)
60 lb. (27.2 kg)
80 lb. (36.2 kg)
When it hardens, the post will be in place.
(Approximately 2 to 3 days under normal
temperature conditions.)
For heavier projects requiring anchoring, the
hole needs to be deeper. The depth for most
heavy posts should be at least two feet.
Another “rule of thumb” is that the hole’s
depth should be 1/5 of the length of the
posts and below the frost line. To determine
the diameter of the hole, measure the
diameter or width of the post. The hole
diameter should be at least 6 inches more
than the post diameter or width. Bracing
may be required to hold the post in place
18 in.
(.45m)
90 lb. (40.8 kg)
0.30 cu ft. (.008 cu. m)
0.45 cu ft. (.012 cu. m)
0.60 cu ft. (.017 cu. m)
0.66 cu ft. (.019 cu. m)
To determine the number of bags needed:
Multiply (length x width x height) divided by yield
Not all package sizes are available in all areas.
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Footings and Foundations
3. Its wall – the structural part resting upon
the footing.
Installing Deck Supports:
Building a deck has become one of the most
popular home improvement projects. An
adequate foundation is essential.
The size of the footing depends on the loadcarrying capacity of the soil and the weight
of the building and its contents. Soils can
vary in their ability to support weight.
To Begin:
1. Dig a hole 12 to 18 inches deep or below
the frostline, whichever is greater.
2. Fill the hole with approximately 2 inches
of gravel in the bottom of the hole.
3. Mix the SAKRETE® High Strength
Concrete Mix as directed on the package.
SAKRETE® Fast Setting Ultra-High
Strength Concrete Mix may also be used
for this application.
4. Fill the remainder of the hole with
SAKRETE® High Strength Concrete
Mix.
5. There are three basic brackets that can be
used as illustrated in Fig. 6.
• Drift pin
• Post anchor
• Corner angle
6. Place a foundation bolt, at least 6 inches
long, in the concrete. Allow the concrete
to harden. (See Fig. 6)
7. Attach the bracket to the bolt, using a
washer and nut. Tighten securely. Place
the plate over the bolt.
8. Bend the final plate around the post, so
that the bracket surrounds the post
complete.
9. Securely nail the bracket to the post.
Fig. 6
A common rule of thumb often used to
dimension footings for lightly loaded
buildings is that the footings shall be twice as
wide as the foundation wall and as thick as
the wall is wide. By this rule, the following
footing sizes would be used.
For 8 inch thick foundation wall (or less)
8 x 16 inch footing
For 10 inch thick foundation wall
10 x 20 inch footing
For 12 inch thick foundation wall
12 x 24 inch footing
Installing A Foundation For A Wall
There is no substitute for a good foundation,
a key part of every building. A concrete
foundation is a small part of a typical
building’s cost but is one of the best
investments in construction. A footing
provides a stable base and directly affects both
the life and performance of the building.
Typical ratio of foundation size to the
wall it supports.
If the structure is heavily loaded, or the soil
conditions are questionable, consult an
engineer or architect. In areas subjected to
freezing, the bottom of the footing must be
placed below the frost line to prevent frost
heave and resultant damage to the building.
A Foundation Consists Of
1. Its bed – earth giving support.
2. Its footing – the widened part of the
structure resting upon the bed.
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The trench bottom should be level and cut
flat so the footing will bear evenly on
undisturbed earth. Where footings are well
below ground, as for a full-basement for a
house, drainage must be provided.
For wet soil conditions, and in order to
assure proper drainage, perforated drain pipes
should be laid around the footing. The
perforated drain pipes should be laid and
drained to suitable outlet with slope of 1 inch
every 12 ft. In no case should the tile be
lower than the footing. Joints between the
tile should be covered with strips of tar paper,
or roofing felt, to prevent sediment filling the
tile during back filling. The perforated pipe
line should be covered with not less than 18
inches of gravel or cinder fill. Filling of dirt
around the footing should be delayed until
after the sub-floor is completed.
Reinforcement
Reinforcing bars (rebar) are often used to
improve the flexure strength of the footing.
For retaining walls or those walls which
must support a lateral backload, vertical
reinforcing bars must extend from the
footing into the wall. Because of the loads
that may be placed against retaining or
basement walls, it is recommended that an
engineer be consulted.
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