How effective is EPS as a thermal insulation material?

Extremely effective ...essentially because stabilised air is such a good insulator.

The thermal performance of a material is measured in terms of its resistance to the flow of heat. This thermal resistance is expressed in R values, the higher the number, the better the insulation.

The R value of the most commonly used Class (Class SL) is 1.13 for every 50mm thickness. Thus, 44mm of this Class of EPS delivers an R value of l 1.0. Does.

EPS absorb water?

EPS is a closed cell and cannot absorb water. During the process of moulding a block, tiny channels are formed between the EPS particles. If the material is immersed in water these tiny channels can be filled with water. After immersion for more than 360 days, there may be up to 6% water content by volume, which has entered the channels.

Even under such an adverse and rare condition of prolonged saturation, EPS suffers little adverse effect. It maintains its shape, size, structure, cohesion and physical appearance. The ability of EPS to resist the adverse effects of moisture is exemplified by its widespread use in floats, marinas and other applications, which involve full or partial submergence in water for prolonged periods of time.

Does EPS have a capillary action?

No. EPS does not have a capillary action. EPS is ideally suited when the insulation material is in contact with the ground.

EPS is said to breathe. What does this mean?

The breathability characteristic of EPS refers to its ability to allow any absorbed moisture to escape when conditions change. It therefore reduces any tendency towards the formation of vapour dams.

In applications where high humidity and temperature differentials are likely, a water vapour barrier such as plastic sheeting should be used. The vapour barrier is best installed on the warm side of the structural component, with the insulation as near as possible to the cold side.

Does age affect the thermal performance of EPS?

No. EPS consists of 98% air and 2% polystyrene, and nothing else. Because of its cellular structure EPS is dimensionally stable, and will not settle over time. EPS used and installed correctly does not deteriorate with age and as such is able to deliver constant R values for the life of the building.

Is EPS durable?

Yes. Because EPS is an inert, organic material, it will not rot and is highly resistant to mildew. It also provides no nutritional value to ants, termites, or rodents.

To prevent damage to EPS by pests and insects seeking to gain access to the other materials in buildings which provide a food source, EPS may be coated with a thin cement slurry.

Provided EPS does not suffer mechanical damage or failure of any fittings that may be used, it should have a life equal to that of the building in which it is installed.

Does EPS burn?

Because EPS insulation boards contain a fire retardant additive, they do not present an undue fire hazard when correctly installed.

Like timber, particleboard and other organic building materials, EPS will burn when in contact with a flame. Due to the presence of the fire retardant additive in EPS, this flame will self extinguish almost immediately after the fire source is removed.

Does EPS give off toxic fumes?

The level of toxicity of EPS in a fire situation is no greater than that of timber and other commonly used building materials; the same toxic gas, carbon monoxide is produced. Also produced are carbon dioxide and soot (carbon). There is no emission of such gases as hydrogen cyanide or hydrogen chloride.

Is EPS cost effective compared to alternative insulation?

Because of the high level of versatility of EPS and the wide range of applications for which it is suitable, its cost effectiveness compared to alternative materials can generally be accurately assessed only on a case by ease basis.

In many applications however, particularly where an element of structural strength is required, EPS is the most cost effective insulation material available.

EPS is the only insulation material that in practical, economic and efficiency terms can be applied to all areas of building constructions – ceilings, roofs, walls, floors and underslab – to provide superior standards of thermal insulation – that’s why EPS is the Ultimate Insulation.