Expanded Cork Agglomerate – ICB
Technical Characteristics
Essential
Characteristics
Density
Performance
Harmonized
Technical
Specifications
< 120 Kg/m3
Coefficient of
Thermal
Conductivity
0.037 a 0.040
W/m.K
Flexural Strength
≥ 130 Kpa
Compressive
Strength at 10%
≥ 110 Kpa
Temperature of
Use
- 180 °C a + 140
°C
Water Vapor
Permeance
386 ng/Pa.sm2
Resistance to
Water Vapor
Diffusion
µ = 7 a 14
Class of reaction to
fire (for exposed
situations)
Classe E-s1,d0
Class of Reaction
to Fire (for ETICS
systems)
Classe B-s1,d0
Length x Width
1000x500 mm /
900x500 mm
Thickness
10 a 300 mm
Other densities are produced, depending on the
application to use, decoration / design, load
bearing, separation, and expansion joints
• HD 9/10 Lbs - 145 a 160 Kg/m³
• HD 11/12 Lbs - 175 a 190 Kg/m³
• REV – Exterior Façade Lining with Cork in
Sight - 140 à 150 kg / m³
General properties of the Expanded Cork Agglomerate:
EN 13170:2008
• Density: 100-120 Kgs./m3
• Thermal Conductivity: 0.040 w/m2 k med. temp.
20º C
• Vapor Permeability: 0.002 / 0.006 g /
h.m.mm Hg
• Limit Pressure: 150 kPa (15 000 kgf / m2)
• Maximum Pressure on Flexible Terms:
50 kPa (5 000 kgf / m2)
• Measurements: 1000 x 500 mm; 915x 610 mm
• Thickness: from 10 to 300 mm
• Operating temperature: -180º C a +140º C
We’ll address the general properties of ICB relevant
to the most significant applications in solutions of
thermal insulation of buildings.
The production of expanded cork agglomerate for
thermal insulation features, in today’s market the
two types of ICB:
Pure thermal and acoustic insulation, with bulk
density generally in the range 110-120 kg/m3.
(STD)
Exterior Façade Insulation and Lining with Cork in
Sight, bulk density generally in the range 140-150
kg/m3. (REV.)
The expanded cork agglomerate with densities
between about 90-140 kg/m3 presents values of
thermal conductivity (at the reference temperature
of 10 ° C) in the order of 0.037 W / mK to 0.040 W /
mk, which guarantees you a "captive place" in the
diverse family of thermal insulation products for
buildings.
Thermal resistances provided be the usual thicknesses of ICB application – 300 to 600 mm – easily
guarantee obtaining the values of K (heat transfer
coefficient) recommended for roofs and walls of
buildings on the current rules of the thermal characteristics of buildings.
The temperature limits for use of cork agglomerate
cover the current range of values found in building
applications - from -180 ° C to +140 ° C – without
the occurrence of degradation problems, deformations or irreversible alteration of properties.
The composition of cork allows exposure to extreme temperatures well above those indicated, a fact
which enables it to withstand without damage the
application of melted bitumen (heated to temperatures well above 100º C) used in the bonding of the
terraced roof waterproofing systems, or use the
ICB in thermal insulation of equipment and industrial installations at extremely low temperatures.
The expanded cork agglomerate slabs have relatively high permeability to water vapor, about 386 ng
/ Pa.sm ². Thus, to avoid the occurrence of unwanted condensation inside the building elements, or
on the ICB slabs themselves, appropriate constructive measures are taken, including the use of vapor
barriers (the inner side) or more permeable to
vapor solutions outside the expanded cork agglomerate boards.
As the organic material that it is, cork agglomerate
is a fuel product, although compared to other
insulating materials, such as certain cellular plastics, it presents many benefits from the behavior
towards fire point of view.
Unlike some of these materials, that can easily melt
at temperatures slightly above 100 ° C, the expanded cork agglomerate is degraded thermally (it
carbonizes) without melting. The fusion of a thermal insulating means, on the one hand the total
loss of strength and shape (with possible implications on the stability and adherence of other
elements connected to it) and on the other hand,
the dripping fuel flow or molten matter, eventually
ignited.
Photo of an ICB “corner” after 30 minutes of exposure to direct
flame at about 900 ºC
The combustion of the expanded cork agglomerate
doesn’t produce significant quantities of other high
toxicity products, other than the carbon monoxide
generated by the thermal degradation of most
organic materials.
In the case of expanded cork agglomerate simple
protection solutions, such as wooden or cast boards
with the right thickness, can be easily adopted.
With the application of paints or protection varnishes
the classification of ICB passes to class B.
The mechanical characteristics of greater importance for the applications of expanded cork agglomerate are the corresponding compressive, cohesion and
cutting strength.
The compressive strength of current cork agglomerate boards present values between 100 and 200
kPa, which allows it to withstand relatively high loads
without showing excessive deformations. The
resistance cohesion, an important property since the
boards must support traction efforts perpendicular to
the major faces, easily exceeds the value of 50 kPa .
Although caused by different actions, the efforts to
cut that the expanded cork boards have to resist
also exceed the value of 50 kPa. Efforts of this kind
may be introduced by elements adherent to the
surfaces of the boards as a result of either the own
weight, or the movements, namely of thermo-hygrometric sources of these elements. Another positive
aspect featuring expanded cork agglomerate is that
it delivers good dimensional stability against significant variations in temperature and relative humidity
that it can be subjected to in certain applications,
such as when performing the roofing insulation in
terrace.
The expanded cork agglomerate has no compatibility issues with other building materials with which it
comes into contact in their usual applications. Thus,
there are no problems of chemical interaction with
substances contained in other products, such
plasticizers, solvents, resins, aromatic compounds
or hydraulic binders, that in other thermal insulation
can lead to premature degradation of one or both of
the products into contact. Note also the wide variety
of adhesives (PVA, contact, etc.) and other binders
(bitumen applied hot or cold, cement-based etc.)
that can be used in the solidarization of ICB boards
to various types of surfaces.
The application of protective or decorative paintings
also raises no problems of chemical compatibility or
adhesion. It has already been referred the excellent
durability of expanded cork agglomerate when
applied to well-designed and well-implemented
constructive solutions.
Note, for example, that the thermal conductivity
determinations made in the Unidade de Tecnologia
da Madeira e da Cortiça of INETI on samples of
expanded cork agglomerate taken from demolished
buildings, with 30 to 50 years of use, showed that,
after all those decades the parameter values
remained the same as those currently. It was also
observed that the collected boards had identical
visual appearance and texture to the new material.
The Expanded Cork Agglomerate has a higher
thermal lag when compared with other systems,
XPS and MW. It is also observed that it is the
one that has the lowest value of maximum
temperature in the receiving surface. The thermal lag of the solutions shows us the diffe rence of time between a change in temperature
on either side of the building system and the
manifestation of said variation on the opposite
side, when the system is subject to a variable
rate of heat transmission. Solutions with a
higher thermal lag contribute to improving the
thermal performance of buildings, as they
retard the loss or gain of heat through the
surrounding.
The Expanded Cork Agglomerate produced by
Sofalca is rated A + in assessing the quality of the
material associated emissions for Indoor Air. This
means that the indoor application of Sofalca’s cork
boards poses no threat to human health, once
again demonstrating that we have a 100% natural
product.
Main applications of expanded cork agglomerate in thermal insulation of buildings:
Because of its characteristics, the expanded cork
agglomerate boards have been used for the thermal insulation of roofs, walls and floors of buildings,
equipment and industrial installations (particularly
cold ones).
The huge increase in demand for thermal insulation, recorded in particular since the early seventies, led to the rapid development and diversification in this area.
In recent years the recognition of health and environmental problems inherent to the production and
use of certain products (fibers of asbestos, CFCs
used as blowing agents of some cellular plastics,release of irritating products foams of urea formaldehyde) has renewed the interest in thermal insulation solutions made with expanded cork agglomerate, particularly in countries such as Austria, Switzerland, Germany, the UK and Italy.
Some examples of application:
• Exterior Walls Insulation with ETICS;
• Exterior Facades Lining with Cork in Sight;
• Insulation of Double Walls (Air Chambers);
• Flat Roof Insulation;
• Thermal Insulation of Roofs and Attics;
• Thermal Insulation of Ground Floors;
• Insulation of Reverberation Transmited Noises;
• Anti-vibration Machine Insulation;
• Thermal Insulation of Cold Rooms.
Thermal Roof Insulation
In buildings, the expanded cork agglomerate (ICB)
finds its “noble" application in the insulation of
terraced roofs, performing the functions of thermal
insulation and waterproofing system support.
The dimensional stability, resistance to high temperatures (necessary to glue the boards to support
bases or waterproofing membranes to the plates)
and mechanical characteristics (compression
and cohesion) which characterize the expanded
cork agglomerate (ICB) are indisputable
advantages.
Those properties and compatibility with the materials of traditional or innovative waterproofing allow
you to perform various solutions with good and
durable.
In roofs where the weight minimization is a tax
(usually metal roofs with sturdy structure, requiring
the application of self-protected waterproofing
membranes) those advantages are even more
notorious over other alternative thermal insulating
materials.
In accessible terraces it may also be possible to
take advantage of the favorable characteristics of
percussion soundproofing (movement of persons,
falling objects) that expanded cork agglomerate
presents, provided they meet some specific construction requirements.
Good acoustic characteristics of expanded cork
agglomerate are also utilized in solutions that use
false ceilings made with this product. In addition to
the insulation provided, the sound absorption of the
boards contributes significantly to improve the
acoustic conditions of the isolated place, reducing
its rate of reverberation (echo reduction).
In sloping roofs the expanded cork boards can be
applied on leaning or horizontal slabs, eventually
protected from accidental infiltration of rainwater
caused by defects in the exterior roof covering.
The mechanical strength and deformability of
agglomerated cork boards (ICB) makes them
suitable for application on horizontal mats (floor) of
garrets of pitched roofs intended for storage. They
just have to be protected from point loads and wear
caused by movement.
Thermal Insulation of Walls (Air Chambers)
In thermal insulation of double walls, expanded
cork agglomerate (ICB) have been placed in the
intermediate wall space, filling it fully or in part.
The total fill, easy to perform on site, has the
disadvantage of placing the expanded cork agglomerate at risk of contact with water accidentally
infiltrated through the outer wall cloth (or condensed in it).
However, the best solution from a technical-economic perspective consists in fixating the insulating
material to the exterior face of the interior cloth
between the expanded cork boards (ICB) and the
exterior cloth, thereby maintaining a drained and
vented air space to the outside.
One way of making the thermal insulation from the
inside is to associate (by gluing) the boards (ICB)
and plasterboards, which impart a mechanical
protection against the action of fire.
Thermal Insulation for Exterior Walls
(Facades)
The interest in the use of a natural and ecological
product, such as the expanded cork agglomerate,
led to the development in several countries, including Austria and Switzerland, of thermal insulation
solutions from exterior walls.
These systems have, as a principle, the gluing of
the expanded cork agglomerate (ICB) boards to
the outer face of the wall and the subsequent
application of an appropriate coating on the insulator. The coating must ensure both its protection
(mechanical actions, rain, fire, etc.) and the final
finish.
As with other systems of thermal insulation from
the exterior walls its application should be based
on a previous technical study. The implementation
of these solutions on site should only be carried out
by specialized teams.
Thermal Flooring Insulation
Thermal insulation of buildings’ floors is only
performed when they are located either on passages or open spaces to the outside, or on
non-heated and ventilated places. The insulation
of pavement on ground floors can be justified if
it is used a radiant flooring system.
In general, and for reasons of protection of the cork
agglomerate, the boards must be applied to the
inner side, which means, over the slab on the
ground.
The floor covering generally is seated over a
screed previously performed on the cork agglomerate with the interposition of a plastic sheet or a
bituminous felt.