Looking for an optimal foamed polystyrene foam to insulate the house we must be aware that the parameters of such a product vary depending on where it is to be used. When we consider the divisions of polystyrene boards, we cannot help but notice that one of the most important focuses on their application in the building.
The most popular classification includes: facade, roof-floor, foundation and parking, and the vast majority of manufacturers use this kind of nomenclature. Of course, the mentioned groups are also not monoliths, so one of the most important insulation parameters is lambda, i.e. heat conduction coefficient. The key task of thermal insulators is to protect the interior of a building and its body from the harmful effects of external factors. Therefore, if we want to determine the level of insulation of foamed polystyrene, we should be interested in the heat conduction coefficient. Lambda also talks about the extent to which a house can be protected from the harmful effects of atmospheric factors. The principle that the better the insulator is, the smaller the lambda is. At present, graphite styrofoam seems to be one of the most interesting proposals in this respect. It was the use of special additives, such as graphite, that made it possible for him to reduce heat transport due to radiation.
Specificity of facade polystyrene foam
Once we have installed the insulation system on the walls of buildings, we must take into account the fact that polystyrene panels, adhesives to polystyrene foam, glues to mesh, plasters, primers and other its elements will be exposed to external factors. Not only wind and rain, but also temperature differences between day and night can pose a serious risk. In such a case, not only lambda, but also tensile strength, TR, is an important parameter of Styrofoam panels, which are classified as facade panels. When talking about a minimum tensile strength value, 80 kPa is usually given, although in this case Styrofoam boards must have technical recommendations or a certificate of conformity. If the product we are interested in does not have such documents, the minimum TR value is 100 kPa. Another parameter to be taken into account is the bending strength described by the abbreviation BS. In this case, the minimum permissible value is 75 kPa.
Specificity of floor and parking polystyrene foam
When choosing floor and parking Styrofoam, one should bear in mind that apart from the heat transfer coefficient, there is also a compression strength, also known as CS(10). Compressive strength tells us a lot about the behavior of foamed polystyrene as a result of the pressure it exerts on the surface of the board. It is not difficult to guess that the harder the foamed polystyrene is, so the higher the CS(10) value, the better. When it comes to floor insulation in a detached house, the value must not be less than 60 kPa. Of course, there are also places where the load on the ground is much higher than in residential buildings. It is then worth looking for polystyrene foams belonging to the parking lot group, which are characterized by CS(10) coefficient at the level of even 150 kPa.
Specificity of foundation polystyrene foam
It has long been known that a house that is really well insulated can only be talked about if it starts from the foundations. It is the contact with the ground that contributes to the escape of a large part of the heat. If we use foamed polystyrene from a group of foundations, we can count on the fact that the problem will be solved. Insulation used on foundation walls is exposed to what can be described as extreme conditions. Even if only for this reason, it is not possible to use foamed polystyrene other than that which is included in the group of foundations. It has specific properties that allow it to perform in quite difficult conditions. It is worth remembering that foundation polystyrene foam is characterized by limited water absorption. The absorption coefficient, referred to as the MVR, which may not be more than 3 per cent, is of key importance here. When choosing Styrofoam from this category, checking the parameters declared by the manufacturers seems to be particularly important. The importance of branded products cannot be ignored, as they are the ones that guarantee the most truthfulness of declarations. It is always worthwhile to make sure that the foamed polystyrene has documents that enable its sale.