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    ISOBOARD extruded polystyrene rigid foam, has closed cells with common sides and is produced on a continuous, fully automated extrusion process, in accordance with international specifications and standards.

    The cost of energy and demand for air-conditioning in buildings is constantly increasing. One of the best ways to conserve energy is to provide high class insulation for buildings.
    The ever increasing costs of heating and cooling dwellings, workplaces, livestock and storage facilities, highlights the need for effective, long-lasting insulation. Insulation should be viewed as a long-term investment.
    With increased energy conservation becoming more and more important, the ability of the product to effectively insulate a building - of whatever type - is equally important.

This is exactly what ISOBOARD achieves. And what is more the product outperforms its competitors when comparing long term retention of thermal resistance.

Physical properties...
Storage & handling...

Cavity Wall Insulation...

Inverted Roof Insulation...

Over Purlin Roof Insulation...
CAD Details...
    ISOBOARD thermal insulation is a high density, rigid, extruded polystyrene insulation board. It has a 100% closed cell structure and is produced on a fully automated extrusion process - in accordance with international specifications and standards.

    In controlled environments e.g. air-conditioned office blocks, wine cellars, etc., the product's payback period ranges from 3 - 5 years, due to savings on energy costs.

    With the manufacturing plant base in Atlantis, Cape Town, the use of advanced, state-of-the-art technology makes it possible to guarantee exceptional properties such as:

       high resistance to heat flow i.e. conductivity,
       resistance to water vapour diffusion and water absorption,
     uniform density distribution,
     very high compressive strength,
     ageing resistance, 
     resistance to bacteria and
     micro-organism growth.
    As a result of all these, as well as many other benefits, ISOBOARD is sufficiently versatile to make it an innovative and cost effective alternative to conventional insulation products. It also means that ISOBOARD can be used in various applications in numerous different markets.
    ISOBOARD is ideal for energy conservation and efficiency in all types of industrial or commercial buildings and in dwellings. Other applications include warehousing and factories, agricultural sheds (where clean and healthy environments are essential), cold storage, cavity wall insulation, flooring, drylining and sandwich panels with various laminates.

Click on a picture for detailed information


Inverted roof system
ISOBOARD is placed above instead of below the waterproofing membrane. This system protects the reinforced concrete slab as well as the waterproofing membrane against thermal shock, thereby extending the life of both.

Cavity wall insulation
ISOBOARD is placed in the cavity to prevent inside walls from heating up in the summer and cooling down in the winter. This helps in providing you with comfortable living temperature inside any building.

Suspended ceilings
ISOBOARD ceiling panels are available in standard ceiling grid sizes and in various finishes-providing both a ceiling as well as insulation.

Nail-up ceilings
ISOBOARD ceiling panels with bevelled and grooved facings are fixed, using the unique concealed fasteners with adhesive thus reducing installation time and saving both materials and labour costs. Minimal wastage, and speed and ease of erection make this system very cost effective and provides a 2 in 1 ceiling/insulation board.

Over purlin insulation
ISOBOARD rigid roof liner supplied with tongue and groove edge profiles generally eliminate the need for "H" / "T" sections normally used for joint supports, or straining wires. A 5mm gap is required when boards are joined on purlins.
Below slab / soffit
Under batten (over truss)
Under Floor
Side cladding
ISOBOARD retards heat flow into buildings in summer.
ISOBOARD keeps heat inside buildings during winter.
ISOBOARD has a k-value of 0,024W/mC (determined in accordance  with ISO 8302:1991(E) or ASTM C518) at 20C mean temperature and 90 day aged. The k-value will increase with time when exposed to air and will also be influenced by water content.
ISOBOARD will only absorb 0.32% (ISO 2896:1987) water and heat flow resistance will reduce by only 3%.
ISOBOARD 's closed cellular structure provides exceptional resistance to water vapour permeability. Heat flow resistance will reduce by a maximum of 8%.
ISOBOARD contains self-extinguishing fire retardants and will not propagate fire in exposed roof applications as certified by the CSIR report no B7510/020 5600 5664.  Click here for Large Scale Fire Tests report.
ISOBOARD is odourless, chemically inert and does not supply nutrition for pests, or support micro-organism growth.
Heat flow (U-valve) reduction compared to uninsulated systems
Application Board thickness From - To
Inverted Roof 50 mm -%
Cavity Wall 30 mm -%
Ceilings 30 mm -%
Over Purlin 40 mm -%
Density ISO 845: 1988 36.1kg/m
Compressive Strength ISO 844: 1978 310kPa
Water Vapour Permeability ISO 1663: 1981 0.78ng/Pa.s.m
Water Absorption   ISO 2896: 1987 0.26% by volume
Coefficient of Linear Thermal Expansion ISO 4897: 1985 67 x 10-6 per C
Thermal Conductivity 
(Average of two tests) 
ISO 8302: 
1991(E) or 
ASTM C 518

ISOBOARD has a dry k-value of 0,024W/mC  at 20C mean temperature and 90 day aged. The k-value will increase with time when exposed to air and will also be influenced by water content.

Combustibility and flame spread4 ISOBOARD performs satisfactory from a flame-spread point of view. 
Refer to report 4 for 'over purlin' installation recommendations.
1   Copies of test reports are available from Isofoam (South Africa) (Pty) Limited upon request.
2 Determination of physical properties of 'ISOBOARD ' rigid foam insulation, dated July 1996, by the Division of Building Technology of the CSIR.
3 Thermal conductivity reports by the general physical laboratory of the South African Bureau of Standards numbered 722/82397/NK9, 10.
4 Reports on the fire propagation properties of 'ISOBOARD ' both dated July 1996, by the Division of Building Technology of the CSIR.


: Plain
100 mm grooved
Edge beveled


: WIDTH : standard 600mm
LENGTH : 1,8m up to 8,0m
(stock in 0,6m increments)


: 20, 25, 30, 40, 50mm stock 
(60/70mm on request)


: Tongue & Groove, Shiplap, Straight edge, Bevelled


: White - others on request.
ISOBOARD contains gases which have been accepted 
in terms of the Montreal Protocol, to be ozone friendly.
ISOBOARD has a high density of 34 - 36 Kg/m and 
a compressive strength of 310 kPa
    Unused materials should be stored in covered areas away from direct sunlight and ultra-violet rays.
    Insulation boards once placed on the roof should not be left exposed. It is recommended that the insulation be immediately covered with the follow up system - e.g.: paving slabs, screed, sheeting, etc. to avoid possible degradation.
    Dust could settle on the face of the board if stored in dusty conditions.  Wipe clean with damp cloth before installation.
    Soot from diesel smoke could be attracted to the product.  If you envisage construction plant in the vicinity after board has been installed, then wipe board down with damp cloth in water softener solution available from us, before installation.
    Surface damage can be expected if product is not handled with care.
    Boards are marked indicating exposed face.  Boards fitted with exposed faces on same side will result in smooth surfaces.