The main material used in the construction of low-energy house - polystyrene

What are the benefits of the polystyrene foam insulation which protect the environment?

Polystyrene foam saves energy. Insulation made of polystyrene foam is used more than 50 years and it fulfills its function in millions of apartments and houses around the world as a insulation against cold, heat and noise. Polystyrene has major benefits in energy saving and environmental protection. Each building insulation reduces production of  pollutant emissions from chimneys and save important raw materials. Less is already known that the primary energy consumed in the manufacture of polystyrene foam is through its use for thermal insulation saved in a very short period - from two months to one year. As you can see, polystyrene insulation contribute for  50 years in large measure to protect the environment.

It is true that the EPS in structures, "disappears" over some time?

No, this is not true. This superstition originated in the early use of this insulating material due to the transgresses against its utility qualities. Polystyrene foam can withstand temperatures which are permanently moving up to 80 ° C, but it is not  resistant to organic solvents. Usage of  polystyrene foam under black or dark blue glass in first types of middle – fenestral filler, as well as using adhesives that contain organic solvents during water insulation, caused the  mentioned "disappearances" of the polystyrene foam. Even more recently similar impact had an excessive increase of temperature in accelerating the production of layered peripheral  panels by over heating together with the usage of improper means during stripping steel forms of the sidewall panels. It is noteworthy that a partial liquidation of polystyrene foam has occurred in  a very short production time of peripheral panels. After their integration into "prefabs" nothing else  happened to them. Subsequent checks showed the absence of polystyrene and this superstition begun to spread among laymen. Therefore simple  principle is valid: if we behave politely to polystyrene foam, its durability is comparable to other building materials.

We all desire to live healthily. Do insulation’s made out of EPS have the desired properties?

Yes, polystyrene foam helps to create a healthy and spatial comfort apartment. Insulation made of polystyrene foam have many good qualities, which are often not well known. Because they are biologically neutral, they are friendly to  health and  the environment. As a material for healthy heat and noise insulation, polystyrene helps to save expensive energy for heating and reduces the spread noise in the building. Properly used polystyrene helps  to maintain favorable and healthy atmosphere in the flat. Each one of us may feel nice inside our four walls. Polystyrene insulation will virtually take no moisture. It is important to know that mold is not caused by heat insulation, but by its absence. A frequent cause is inappropriate technical design of structures, or inadequate ventilation etc.

What are the requirements of the polystyrene foam insulation  in terms of recyclation?

EPS is a smooth material in terms of recycling and is very suitable for it. Most common ways of recycling are :

• possibility of re-processing it into another EPS products
• developed industry polystyrene concrete
• horticultural substrates (plants will thrive better in soil with EPS)
• heat - insulating powders
• thermal recycling

When depositing the EPS on a junkyard, it does not release any water-soluble substances that could pollute groundwater. Granular waste polystyrene foam is thus used in agriculture and horticulture to improve heavy soils and as a baking expedient. This shows that polystyrene may also contribute in this form to our environment. Waste generated directly in the manufacture of foamed polystyrene is largely re-used again in the production cycle, and further i tis used as an ingredient in concrete, plaster and insulation. Higher degree of utilization of usage, for example polystyrene  packaging is not a question of technology, but the question of organization and gathering these materials.

It is true that, for foaming the  polystyrene, freons are used?

Not true. Expanded polystyrene is not foamed by  using freons. Production of EPS takes place in simple steps, which the basic raw material are solid polystyrene beads containing blowing expedient, which are  heated by steam. Due to the influence of heating, the blowing expedient evaporates and it is dispersed in the beads. Polystyrene increases its volume more than  20 - to 50-times and inside the beads a closed cell structure is created. Polystyrene is then in a confined space - in the form - foamed into the necessary shape. As the lowing expedient pentane is used - a low boiling hydrocarbon with a boiling point around 37 ° C, which has no effect on the ozone layer – unlike CFCs (freons). It is therefore wrong to relate the damage done to  the ozone layer of our planet by freons - different spray propellants with  foam polystyrene. Either during production or in applications of EPS freons are not used, or are not present and therefore can not escape into the environment.

How is it with the presence of formaldehyde, styrene, or radioactivity in EPS?

Expanded polystyrene is very strictly monitored in terms of harmful substances content. First - there is no link between formaldehyde and polystyrene foam. Polystyrene is a substance that does not contain formaldehyde! Second - a tiny low traces of styrene were detected in freshly produced polystyrene. This was able to be measured after  the development of a particularly accurate and sensitive analytical methods. These tiny concentrations can be found in many foodstuffs, such as strawberries, beans, beer, etc., for a long time. And third – not even in connection with radioactivity and EPS there is no reason for concern. Alpha, beta and gamma radiation, or the occurrence of radon were not  been found in polystyrene.

There is the possibility of using polystyrene on other fields?

Yes, polystyrene foam has wide application. Expanded polystyrene is found in many areas of our daily lives. Flowerpots made of EPS are known almost 50 years. Flake granules of polystyrene are now obvious part of the ceramic containers for flower growing,it  serves as a drainage and ensures a healthy nutrition and rapid development of plants. Similarly, in establishing so-called. green flat roofs, in agriculture and horticulture polystyrene foam plays an important role. Major application is as an excellent fixative and protective packaging for  new electronics, kitchen robots and many other fragile or sensitive products. Health friendly properties of polystyrene are also demonstrated proved  when it is used as a packaging material for foodstuffs. From portable refrigerator containers to containers for transportation of fish and vegetables, it shows the range of possibilities of this material usage.

What is the truth about  the polystyrene foam to releasing "toxic fumes" during conflagration?

Expanded polystyrene during conflagration does not release more harmful substances than any other commonly used building materials of organic origin. In particular, it is known that during combustion of natural and synthetically manufactured materials, certain substances with  harmful effects occur. Experiments show that foam polystyrene is nota n exeption in this matter. When burning polystyrene arises almost exclusively carbon monoxide, and in such low concentrations that rats exposed to these products of combustion in many cases survived, but were killed during the same experiments with  burning wood. Alternative materials used for  insulating substances - such as cork and wood fibers – have  substantially higher concentration of CO2 during combustion than polystyrene. This is also true for almost all residential furnishings - furniture, curtains and carpets. Risk of conflagration of expanded polystyrene is also decreased by  the fact, that  it comes to construction business  exclusively in self-extinguishing arrangements.

It is necessary for insulation used in construction to „breathe“?

First, you need to realize that through walls, only cca 4% of air and moisture exchnage is done. Most of the moisture should be led out (by ventilation) otherwise (windows, chimneys, hoods, etc.). If this 4%-for example, had fallen to 2%, i tis not a problem for the house climate. Therefore, millions of wooden buildings worldwide, have vapor barrier as a part of the wall construction. For ventilated structures low insulation factor is more advantageous, while for unventilated structures (single-roof, contact facade insulation systems) high vapor permeability (low m) is less favorable, because above  the thermal insulation material with significantly higher diffusion resistance (renders and plasters , hydro - insulation) is located. These materials will retain rapidly penetrating water vapor,  in the cold part  of the structure, and then it often condenses in larger extent. For example, for the single – facing roof is best to use strong – closed water vapour insulation material which are also highly diffuse. Materials with a low m are less effective in this case and almost always require a vapor barrier to be added. EPS is a material with an average water vapor permeability (factor m = 20 to 50) and is used mostly in unventilated structures such as external wall insulating systems and single flat roofs.

It is necessary to use personal protective equipment while  working with EPS?

There is no need to use personal protective equipment. Unlike thermal insulation based on mineral fibers, it is not necessary to use personal protective equipment, such as protective clothing, goggles, gloves, respirators etc. when working with EPS.

Information was drawn from documents of the Association EPS Czech republic. Association members are manufacturers of raw materials (expandable polystyrene), manufacturers of applications of EPS (foam, expanded polystyrene) and other companies and professionals operating with EPS in Czech Republic and Slovakia. The association is a member EUMEPS, European Manufacturers Association EPS.