In-site stability
Polyurethane spray foam can be used in applications which experience exceptional extremes of temperature, from -200°C to +100°C.
Water absorption
The water vapor permeability of polyurethane spray foam is low and is enhanced in most building applications by the incorporation of a moisture barrier of polyethylene film or aluminum foil.
Fire properties
Like all organic building materials - wood, paper, plastics, paints - polyurethane spray foam is combustible, although its ignitability and rate of burning can be modified to suit a variety of building applications and it can be formulated to meet the relevant national regulations.
Polyurethane spray foam are usually used at lower thicknesses than other insulants, which means that their heat or fuel contribution to a fire is low compared to other, thicker insulating materials. The overall fire performance of the polyurethane spray foam insulation panel can be significantly enhanced by the material that is used to face the panel - for example, steel.
Independently monitored, large-scale tests of buildings incorporating polyurethane spray foam and polyisocyanurate (PIR) foam insulation carried out in the USA and Europe have concluded that, properly used, these materials do not add to the severity or serious hazard of fires.
Lightness
At low densities (e.g. 30kg/m3), the volume of polyurethane polymer in polyurethane spray foam is around 3 per cent. The remaining 97 per cent of the foam is gas trapped within the cells, which provides the low thermal conductivity properties.
The lightness of the polyurethane spray foam is an important aspect in terms of transportation, handling and ease of installation.
Chemical resistance
Polyurethane spray foam provides excellent resistance to a wide range of chemicals, solvents and oils.