Myth 3: The Green House Must Breathe
Surprisingly, buildings simply do not have the physical ability to “breathe”. Most often, speaking about the breathing of a building, it refers to the removal of moisture, which should not condense on walls or other surfaces.
To explain this physical process, there is the concept of vapor permeability, that is, again turn to Wikipedia, the ability of a material to pass or retain steam. As a result, the house must be insulated in such a way as to prevent the formation of excess moisture, which can lead to the appearance of mold, fungus, and harmful microorganisms. And provide ventilation through ventilation.
And thermal insulation is responsible for ensuring that cool air does not escape from the house and warm air in winter. Thermal insulation creates comfortable indoor conditions, saves heating or cooling costs, and improves the quality of air that you and not your home breathe. And so that condensate does not accumulate inside the wall and roof, it is necessary to correctly determine the thickness of the insulation. This applies to all types of thermal insulation materials.
The material does not lose in environmental friendliness if it needs to be updated.
Environmental friendliness is a comprehensive concept that considers the entire product life cycle. From production through transportation and operation to disposal.
We have already said that polyols can be produced from plant materials or carbon dioxide, and with regard to the service life, in 50 years polyurethane foam can save at least 100 times more energy than is required for its production. And if the service life of the building is 50 years and after 30 years it will be necessary to replace the thermal insulation, then the environmental load will double: after all, the house will have to be insulated twice.
As for the transport component in the ecological footprint of production, 100 mm PIR have insulated as efficiently as 260 mm panels with mineral wool or a 1.68-meter thick brick wall. It is easy to calculate how much less transport is needed to transport polyurethane foam insulation.
In Europe, studies were conducted on a sample of polyurethane, which lasted 33 years.
It turned out that the thermal conductivity of the sample changed slightly and amounted to 0.0272 W / (m * K) with a slight decrease in thickness from 60 to 59.05 mm.
As for the production and reuse of PIR, unsuitable for standard operation polyurethane can be used as the basis for window frames, partitions, doors, countertops, and even ship furniture and high-speed trains. Because polyurethane in any state retains its properties: it does not rot, is resistant to mold and moisture.
The illusion of high cost can be attributed to the same myth. Indeed, at the time of purchase, PIR is more expensive than other heaters. However, if you consider what the cost of heating is, the cost of replacing popular and supposedly environmentally friendly heaters, when they crumble or draw water, estimate the usable area that is formed by using a thinner PIR and try to evaluate comfort from the once and for all solved problem, then the cost will turn out to be comparable to cheaper materials, and in some cases will be even lower.
Says Ilya Evdokimov, head of the R&D center ProfHolod:
“The environmental friendliness of PIR insulation can be compared with the environmental friendliness of elastic PPU, the well-known“ foam rubber ”used in the manufacture of mattresses. “Foam rubber”, consisting of open cells, is compressed when a load is applied, and then takes its original shape. PIR – rigid polyurethane foam, the elasticity of which is negligible. Compared to “foam”, PIR consists of closed cells in which air convection does not occur. PIR has high strength and can be destroyed only under significant load, for example, when struck with a hammer.
With such destruction, the blowing agent, in our case, pentane hydrocarbon, will really be released from the cells, however, all environmental indicators will remain normal. The maximum permissible concentration (MAC) of pentane in the room is 300 mg / m3. Take a panel 100 mm thick and 1185 mm wide.
The average cell diameter is 40 microns. We get that when the panel is cut, 2666 cells are destroyed. One cell contains no more than 0.13 nanometers3 of gas. To achieve the MPC, it is necessary to break 1382 panels in an unventilated room with a volume of 100 m3. It is impossible to achieve such conditions in life.
Foaming agent diffusion usually occurs over the decades. At the same time, the cells do not collapse, and the amount of foaming agent freed statistically tends to zero.
In addition, thanks to the closed cells, the material does not retain moisture, thereby eliminating the appearance and development of bacteria and fungi. ”
Myth 5: Green House is a house with LED lamps
According to British experts, 78% of all electricity consumed is used to heat a house. 11% falls on water heating, 7% on other electrical appliances and only 4% (!) On lighting.
So even if you replace all the lamps with LEDs, but put two TVs instead of one, then your savings will bring a meager result. While thermal insulation at home with PIR with a coefficient of thermal conductivity of 0.022 will save you the cost of heating and or heating.
In the UK, according to experts, improved thermal insulation at home can save about 400 pounds or 33 thousand rubles a year. In our country, only gasoline prices are growing rapidly, so the amount of utility bills, of course, is less. Till. But nonetheless.
Indeed, in some areas of construction, natural materials, brick, stone, wood, and conditionally natural, like concrete, are irreplaceable. Entirely made of modern materials, it is still difficult or impossible to build multi-story buildings or bridges. However, in terms of insulation, construction speed and ease of installation, PIR is an excellent choice. Especially if you care about the environment.