Performance

Structural

STYROFOAM™ boards are available in a range of compressive strengths to suit different loadbearing requirements.

Fire

Information on aspects of fire performance of extruded polystyrene in building applications is given in BS 6203: 1991, 'Fire characteristics and fire performance of expanded polystyrene materials used in building applications'.

STYROFOAM products contain a flame retardant additive to inhibit accidental ignition from a small fire source, but they are combustible and if exposed to an intense fire may burn rapidly.

During shipment, storage, installation and use STYROFOAM products should not be exposed to flames or other ignition sources.

Fire classification is based on small scale tests which may not reflect the reaction of the product in its end use state under actual fire conditions.

STYROFOAM products should, when installed, be adequately protected from direct exposure to fire.

STYROFOAM products achieve Euroclass E (reaction to fire).

Temperature

Polystyrene products will melt when brought into direct contact with high temperature heat sources: for Dow STYROFOAM boards the recommended maximum working temperature is 75°C.

Water/Moisture

STYROFOAM is highly resistant to water absorption. STYROFOAM boards are very resistant to the passage of water vapour and are unaffected by repeated freeze/thaw cycles.

Biological

STYROFOAM has low susceptibility to rot: mould or fungal growth is therefore minimised.

Chemical

STYROFOAM boards are resistant to most commonly occurring construction materials such as lime, cement, plaster, anhydrous gypsum, solvent-free bituminous compounds, water-based wood preservatives, as well as alcohols, acids and alkalis. Certain organic materials such as solvent-based wood preservatives, coal tar and derivatives (creosote), paint thinners and common solvents such as acetone, ethyl acetate, petrol, toluene and white spirit will attack STYROFOAM, resulting in softening, shrinkage and even dissolution, with a consequent loss of performance.

The use of solvent-free adhesive is recommended. Advice on compatibility with polystyrene foam should be sought from the adhesive manufacturers prior to application.

Sunlight

Protect STYROFOAM from prolonged exposure to intense sunlight to prevent degradation of the surface of the board.

Durability

Properly installed, STYROFOAM boards have a service life comparable with the building or structure.

Environmental

STYROFOAM is not bio-degradable in the environment and does not present an environmental hazard in the water/soil compartment.

Disposal

STYROFOAM can be:

• recycled mechanically.
• recycled chemically.
• used as land-fill (no harmful effects).
• incinerated under control to recover the energy content.

Common Properties of STYROFOAM products
Properties	Standard	Unit	Value
Specific heat capacity	—	kJ/kgK	1.4
Coefficient of linear thermal expansion	BS 4370: Part 3: 1988: Method 13	mm/mK	0.07
Working temperature range	—	°C	-50 to +75
Fire classification: reaction to fire	BS EN 13164 and BS EN 13501: Euroclass E