The technology of polystyrene foam insulation

Expanded polystyrene is one of the most popular heaters used at all stages of the private construction: for the foundation, basement, walls, roofs, etc.Low thermal conductivity, low weight, durability and cheapness - not all the advantages possessed by the material.In today's article we will talk about technology polystyrene insulation with his hands.

overview performance

foam or polystyrene foam prepared from a polymer mass, which is under high pressure is exposed to water vapor.The resulting polymer beads are increased ten times, and the foam is obtained.In fact, millions of air bubbles enclosed in the thinnest polystyrene shell, which account for only 2-3% of the total volume of the material.Styrofoam - is solid and strong enough foam is created with one purpose - to keep the heat in the room.

main characteristics of expanded polystyrene:

1. Teproprovodnost - mineral wool is the main competitor of polystyrene foam, but if you compare their heat conductivity, it is clear that mineral wool significantly loses.At this level of thermal conductivity of polystyrene can be varied by selecting different material density - the denser the structure, the higher thermal conductivity.
2. Water vapor permeability - a conventional foam zero vapor permeability as dense polystyrene shell air bubbles are not capable of passing the wet evaporation.Extruded polystyrene is different from the usual, because it uses cutting molding method, which means couples can climb in through the slits.
3. Dehumidification - the situation with the water absorption is somewhat different.The usual polystyrene, submerged in water, absorbs 10 times more water than thick extruded polystyrene.For this reason, it is recommended to use extruded polystyrene for the exterior decoration of houses.To foam served for a long time and went on a qualitatively retain heat, it must be properly protected from the wet.
4. strength - extruded polystyrene is ten times stronger than usual, because it has a more dense structure, and accordingly tighter bond between the molecules.Flexural strength is from 0.4 to 1 kg / cm² while a conventional polystyrene it is 0.02-0.2 kg / cm².
5. Soundproofing - many sellers foam argue that it is equally well protected from the cold and the noise, but this is not true.Air bubbles can only slightly dampen impact noise and only if the foam layer is laid thick and subject technology.With air noises that usually give us discomfort, the foam can not cope.
6. Environmentally friendly - there is a perception that the polystyrene foam insulation from the inside, and in general, the use of this material in the construction of residential houses will be detrimental to human health and the environment.In environmental terms polystyrene safe, but there are some reservations.Firstly, the oxidized material outdoors, it happens especially quickly with the usual non-extruded foam.During oxidation in the atmosphere, toxic substances: toluene, formaldehyde, acetophenone, ethylbenzene, methanol, etc.That is why after the installation of the foam insulation you need to immediately block insulation and finish.
7. Flammability - if you look at the advertising polystyrene in the construction market, you will notice that many manufacturers have focused on the fact that their production in terms of fire safety harmless wood.In fact, for fire wood needed a lower temperature than for the ignition of expanded polystyrene.But before you ignite it will melt and thus give off toxic fumes.If the manufacturer claims that it is capable of polystyrene flame is extinguished, do not believe.To see the falsity of the statement, read enough with the Russian GOST 30244-94, which states that polystyrene foams are a group of the most dangerous material flammability - T3 and T4.
   Many manufacturers presenting their products, use European standards for determining the flammability of biological, chemical and integrated response.So it turns out that the most dangerous and highly flammable material is wood.Styrofoam Toxicity is determined approximately, since there is no way to accurately compare the products of combustion of foam and wood.As for the diligence that can provide accurate information about the product, then it simply does not include a common list of specifications.The user receives only part of the information that is inaccurate characterization of the chemical and biological analysis foggy.Also it is necessary to take into account that, over time any foam, even with flame retardant additives, literally ages and loses its quality indicators, including flammability class (it becomes more susceptible to fire).
   
8. Durability - the rate depends on many factors, ranging from the quality of the material itself, ending with the operational conditions and climate.An important role is played by the observance of assembly technology and the use of suitable adhesives and protective compounds.If wall insulation polystyrene foam produced according to the rules, the material guaranteed to last for 25-30 years.

How to choose a polystyrene

The most important mistake in selecting polystyrene for insulation boards is wrong calculation thickness.Many people think that the thicker the insulation, the better, but besides that it leads to an increase in cash expenses, so also reduces the life of the heater and the wall.

foam - one of the cheapest heaters, with the laying of which can be managed without professional skills.That is why the demand is so great, and because the demand creates supply, types of expanded polystyrene is very, if not too much.A layperson immediately entangled in such a variety, and he had no choice but to trust the seller consultant.This deftly played by many manufacturers, not promoting something that fits exactly in your case and what you need to sell.So before you go for the foam, carry out a detailed analysis of what you'll be warm for what purposes, especially the climate in your area, financial capacity, etc.

If you need to insulate the walls of the house from the outside, choose a polystyrene PSB-S is not less than 40 marks.If you see a number on the label 25 or less, the material is not suitable for any construction works.After defining the brand, select the density of the material - for PSB-C40 it can vary from 28 to 40 kg / m³.Be sure to pay attention to the density, not only on the mark!

Tip: If you are assured that the density of Styrofoam chosen not less than 35 kg / m³, ask how it was produced.The conventional method provides a foam density less than 17 kg / m³, while a high-quality material can only be made by extrusion (high pressure).

Finally, break off a small piece from the corner of polystyrene - if the edge break off cleanly, and will be visible at the turn of small balls, so the quality of the product is low.A quality extruded polystyrene breaks off smoothly, and at the turn of you will see the regular polyhedra.

Features polystyrene insulation

Despite many claims to the expanded polystyrene, for many years he remains the most popular insulation.The reasons are more than satisfactory: it is cheap, easy to cut, easy to assemble, is a long and well-kept warm.However, most importantly, what to remember when warming - as quickly as possible to close the expanded polystyrene insulation layer to protect it from direct sunlight and oxidation.For this purpose, special plasters mineral-based exterior finishes and plasterboard - for internal.Next, we describe how to use polystyrene foam for thermal insulation of the main parts of the house.

Insulation of the basement and plinth

Since the construction of any house begins with the foundation, consider the technology of its insulation first.If you Insulate the foundation, it immediately will increase the thermal insulation performance of the whole house, as well as prevent the freezing of the soil.This means that the floor insulation, the walls and the roof, you will need less money, time and effort, and the foundation last longer, since there would be an annual freeze and thaw.

technology foundation polystyrene insulation:

1. insulate the foundation can be under construction house and even after its commissioning.In the second case, the foundation must be completely dig around the perimeter, cleaned of dirt, rust and any spots.If the outer walls are the remains of the roll of waterproofing, they need to be removed.Insulate foundation walls as you can and the outside and inside, but experts as one is advised to do it outside.
2. for insulation of the basement and plinth best to use extruded polystyrene, taking into account the choice of its density and the estimated thickness.The density must be at least 35 kg / m³.
3. Before attaching the EPS, it is necessary to make waterproofing the external walls of the foundation.For this fit any materials except asphalt mastic on organic solvents, as in contact with polystyrene she quickly destroy it.If you want to use mastic, choose a mixture of water-based or polymer-based.
4. Now you can attach the polystyrene plates.Use a special adhesive designed exclusively for the polystyrene.Apply it around the perimeter and a couple of bars in the center, wait a minute, that he podzastyl and press firmly to the wall for 2-3 minutes.Perform the mounting plates on the level to prevent distortions in the connection point.If you want to lay two layers of polystyrene foam, are attaching sheets of the second layer so that their seams are offset with respect to the joints of the lower layer half plates (ligation sutures).Slots remaining after the fixing plates, fill with foam.
5. Even extruded polystyrene does not have high mechanical strength and susceptible to various injuries, including damage by rodents.For this reason, after laying the tiles from the top is necessary to attach the reinforcement mesh or wooden boards.Fix them on the perimeter of the foundation dowels to the height of its filling.If you are using a grid over it is necessary to put cement plaster with waterproofing additives.
6. If you warm up you house foundation located on the wet ground with a high level proleganiya groundwater, it is necessary to make a drainage.To do this around the perimeter of the house set the perforated pipe, putting it on the powder sand and gravel.Cover up the foundation in this case the need to sand or soft soil.
7. For warming plates polystyrene cap must first stick to the prepared foundation, and after 1-2 days, when the glue hardens, strengthen fixing plugs-umbrellas.Each plate should be strengthened by such dowels 3-5.To reduce the number of fasteners which can be installed in umbrellas joints between slabs.To protect the Styrofoam from atmospheric and mechanical influences it is necessary to lay the masking grid and the surface of the mineral plaster mixture.You can then proceed to the decorative trim.

Despite the popularity of the practice, the foundation is better not to insulate foam - this is not quite suitable for such material operational loads.Experts recommend replacing polystyrene stronger counterparts: Penoplex or polyurethane foam.

Wall insulation

Many people mistakenly believe that there is no difference between the thermal insulation of the walls inside and out, moreover, to insulate the wall from inside much easier, because you can do it at any time of the year and do without the equipment for work at height.However, in reality the situation is quite the contrary - experts recommend not to insulate the wall from inside unless absolutely necessary.A need for this can only occur if the house is an architectural or historical value, or if the insulation of facades with polyfoam impossible for technical reasons.

What problems arise in the inner wall insulation:

1. dew point - a place where the cold temperature from the street faces the heat coming from inside the house - moves into the premises in the space between the heater and the wall.As a result, there is accumulated dampness, developing fungus, mold, the wall collapses.
2. Since moisture is gradually destroyed wall, the service life of the building itself is also reduced by several times.
3. Indoors, whose walls are insulated on the inside, there is a constantly high humidity, and if you do not provide additional ventilation of rooms, interior decoration and furniture will also begin to deteriorate.Moreover, due to the change in the internal climate of residents suffer health.
4. For insulating walls inside the insulation layer should be thicker than the exterior.This leads to increased costs and reduce the useful interior space.

All of these factors in the amount of lead to the rapid destruction of the walls of the house and uncomfortable accommodation, but because it is better to hold a polystyrene foam insulation from the outside.More useful information about this can be found in the article "Warming of house facade foam."

Winterizing floor

Even if you have warmed the foundation and base, it does not mean that the floor insulation can be neglected.Particularly acute, this problem for the residents of the first floor high-rise buildings and owners of private houses.Warming of the floor expanded polystyrene can significantly reduce heating costs, and eliminate the causes of "household" diseases associated with hypothermia.

If you work with the floor on joists, insulation for better use of polystyrene PSB-C15, since the main burden is not on them but on the joists.In power for thermal insulation of floors on the first floor of 10 cm is required, and for intermediate floors - 5 cm

for insulation of concrete needed a more durable polystyrene from PSB-C35 and higher..First carry out a rough alignment of the boards of various capacities, but experts advise to make insulation leveling screed.Before you put the insulation boards on the floor lay a waterproof film.Styrofoam cover 2 cm layer of cement mortar, wherein the reinforcing mesh utaplivajut then make finishing screed thickness of 5-8 cm. Process gaps filled with foam or glass perimeter.

Warming attic

In recent years, many began to remodel cozy lofts in the attic, thereby increasing the useful living area of ​​the house.But that there was really warm and comfortable, the walls and ceiling must be qualitatively insulate.In this case, a particularly strong pressure on the surface is not, but the insulation is exposed to different influences.Since the attic under the roof, all the warm air rises from the house is there, and if you do not create a serious obstacle for him, he just left the house, and you will spend a lot of money on heating.For this reason, in the attic is always a few degrees warmer than the lower floors of the house.

ceiling of the attic is more prone to condensation than other floors in the house, so it must be not only qualitatively warm, but also take care of vapor barriers and ventilation.

attic Warming of polystyrene occurs on more stringent requirements.More information on this topic is discussed in the article "Thermal insulation foam roof."

following video - polystyrene insulation of attic premises:

Styrofoam can serve as an excellent tool to create a warm home for many years, but only if you carefully examine all aspects of its use.