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Considerable part of heat which is made by means of the warming devices often is spent in vain because of significant heatlosses. This problem is especially widespread in old houses in which the heat-insulation layer has not been provided at construction stage, and windows and doors are cold source. The ideal solution of this of problems – warming by polyurethane foam which advantages, shortcomings and features will be considered in this article.
Warming by polyurethane foam: production technique and putting material
Such material as polyurethane foam is received as a result of mixing of two components – polyol and diisocyanate. In spite of the fact that both of these components are toxic and represent threat for human health, as a result of their mixing quite safe polyurethane which does not bear any danger turns out and at contact with other substances does not react. Moreover, the material received as a result of two toxic agents is quite often used even in the food industry.
Process of production of polyurethane is followed by active gas emission as a result of which large amount of carbon dioxide is formed. Thus, it appears in thin polyurethane cover which provides high rate of heat-insulating material properties.
All this procedure is carried out by means of special gun in which very high pressure, and temperature which in it is maintained is 45 °C. As a result of such influence the particles similar to dust are small mix up then they are sprayed on surface, allowing to foam and harden.
In order that the received material had all necessary characteristics, its making components (polyol and diisocyanate) have to be in equal proportions. If the quantity of one of components is more, it will have an adverse effect on characteristic of material. Exceeding of quantity of diisocyanate leads to the fact that foam quickly “sits down” and collapses, without performing the main function – heat insulation.
Polyurethane foam in which there is more polyol is characterized by high fragility, though is capable to perform the functions fully. Apparently, the quality of warming by this material directly depends on that, initial components and also from quality of the equipment used for this purpose are how well prepared.
Mixing of components can be carried out qualitatively only on condition of availability of special high-pressure units. Therefore it is necessary to pay attention to that what equipment is used by the firm chosen by you. Production of polyurethane foam in the conditions of insufficiently high pressure leads to significant decrease in heat-insulating material properties.
Kinds of the polyurethane foam used for warming
In spite of the fact that the polyurethane foam manufacturing techniques one, final product have several versions differing from each other in properties and characteristics. Let’s consider each of options in more detail.
Light open-mesh polyurethane foam. Heat conductivity of this material is often compared to the characteristics inherent for mineral wool, at the same time it possesses the same shortcoming – hygroscopicity. The cost of light polyurethane foam is much higher that does its use not too justified.
If desired to use light open-mesh polyurethane foam for warming, it is necessary to take care of availability of layers of waterproofing and vapor barrier materials and also to think over facade ventilation system to delete excesses of moisture. But if to compare this option to the same mineral wool, then It should be noted that sound-proof indicators in this case will be higher.
This material is extremely seldom used as heater for roof or facade as he not too copes with the task, being susceptible to influence of external factors. And here if it is about need of warming of internal overlappings or partitions, then its use is quite justified.
Closed cell polyurethane foam has much more acceptable characteristics: well grabs on any surface (the exception can make unless polyethylene) and it is not hygroscopic at all. Depending on consistency value, is divided into three categories:
low density (28-32 kg/m ³). More often than other options it is used for sputtering on walls and ceilings for the purpose of creation of heat-insulation layer. Coefficient of thermal conductivity of this material makes 0.02-0.028 that practically corresponds to indicator of air (0.022). As for vapor permeability, the indicator is closest to wood – 0.05;
material of average density is intended for filling of cavities. Its only difference from the previous material – the smaller speed of expansion that allows to use comfortably it for filling of space of layered walls, etc.;
polyurethane foam of the increased density (40-80 kg/m ³). It is intended for warming of surfaces which should be exposed to serious mechanical loadings. At the same time more high density provides also higher coefficient of thermal conductivity.
How much is warming by polyurethane foam
Considering question of the prices for warming of polyurethane foam of 1 sq.m., It should be noted that cost directly depends just on what type of material has been used. The cheapest – light open-mesh polyurethane foam. However, in order that work has been carried out not in vain, it is necessary to spend also for waterproofing and vapor barrier materials that in total will lead to the same expenditure, as well as heat insulation material of average density.
Of course, a lot of things depend on thickness of the put layer, it has caused expense, but similar subtleties are discussed individually just before the beginning of work.
Helpful advice! If desired to pick up the most favorable material, it is possible to request at the same time in several firms calculation of cost of works taking into account the required area of covering. So you obtain information on all relevant offers and will be able to give preference to that option which will suit you more than the others.
Warming by polyurethane foam: pluses and minuses of use of technology
The technology of warming of the house polyurethane foam has the mass of the most various responses, both positive, and negative. Let’s consider what it is more, advantages or shortcomings and whether it is worth giving preference to this type of heater.
Positive characteristics of warming by polyurethane foam: responses of users
The main advantage of this way to provide to the building qualitative heat insulation, is — high performance. Thanks to the cellular structure, this material perfectly keeps heat. But there are also other advantages of which you should not lose sight:
the lack of seams and joints excludes emergence of such phenomenon as, “cold bridges” that positively affects heatpreservation;
it is possible to raise dust polyurethane foam on any, even difficult on design or surface texture;
low level of hygroscopicity of material positively affects waterproofing qualities of surface;
polyurethane foam grabs on any surfaces except polyethylene. It is interesting that this positive at first sight, quality it is possible to carry also to shortcomings as it is almost impossible to wash polyurethane foam, and solvent for it does not exist. The only way to get rid of it – to tear off manually, and it practically always leads to essential surface damage on which it has been applied;
the operational term of polyurethane foam with full preservation of all technical characteristics of material – 25 years. After that heat insulation continues to work though heat conductivity of sputtering increases;
the sputtering is made quickly enough so carrying out all necessary works will not take a lot of time;
material self-extinguishing and does not sustain combustion even in case of fire;
the coefficient of vapor permeability makes 0.05-0.06 that allows to take away effectively excesses of moisture after warming of walls polyurethane foam.
Helpful advice! All shortcomings and defects come to light within the first year of operation. If for this period no shortcomings have been revealed, the next 25 years it is possible not to worry about it.
Warming shortcomings polyurethane foam: minuses and pluses
Apparently, the amount of positive characteristics of this material is high, and, one may say, that all these positive aspects quite justify its use as heater. However, polyurethane foam also has shortcomings, and about them it is better to foreknow:
the cost of sputtering of polyurethane foam is about 1.5-2 times higher, than if to use mineral wool as heater;
respect for technology of sputtering directly determines the term and quality of its service. Only on condition of availability of the high-quality equipment and the corresponding experience of the master, it is possible to receive desirable result;
warming by polyurethane foam the hands is very difficult and often unjustified process. In many respects it is connected with the high cost of the required equipment and also lack of due experience in this sphere;
polyurethane foam does not burn, however, in case of fire it allocates a lot of dangerous caustic smoke;
as a result of influence of ultraviolet rays foam spoils, losing the initial exterior, changing color from white with dark brown.
Fortunately, the most part from the offered shortcomings can be neutralized, for example, having invited for work of the experienced specialist with the equipment and having provided surfaces finishing finishing which will protect further polyurethane foam layer. But the major restraining factor for warming in polyurethane foam sputtering — the price which, nevertheless is quite justified by long life cycle of covering.
What conditions are necessary for warming by polyurethane foam: responses and councils
In order that carrying out expensive the procedure of sputtering of polyurethane foam was not vain, it is necessary to carry out qualitatively all preparatory work and to create necessary conditions. It concerns both warming of walls in the apartment from within, and other works: warmings by polyurethane foam of roof, facade, etc.
First of all it concerns surface preparation. Even at good adhesion it is necessary to remove everything that can be showered, for example, old paint.
Helpful advice! One of the worst enemies of polyurethane foam sputtering – greasy spots. They shall be neutralized and removed prior to work.
After that it is necessary to secure all surfaces which are not subject to warming. As it was already mentioned, foam cannot almost be washed away so it is necessary to close everything polyethylene film, having properly fixed it by adhesive tape, not leaving gaps.
If it is about warming of penthouse or roof, then for this purpose there are two ways. In the first case constant furring on which evaporate foam is prepared. Other option of warming of roof polyurethane foam – temporary framework which represents two planes located in parallel.
If the sputtering is carried out on external walls of the building, whether it be warming of hangar or the house, availability of finishing finishing is considered obligatory. By the way, warming by polyurethane foam of hangar or warehouse – very widespread phenomenon. It is important to take care of that on wall it was possible to fix covering as foam of it will not allow to make only. For this purpose in advance fill wooden or metal levels which serve further as fastenings.
For example, if you have decided to make warming of the house polyurethane foam under siding, the price of work will be slightly higher as will include mounting of fastenings and all necessary fastenings for further fixing of panels. Though it is worth recognizing that it is esthetic, and, above all – efficiently.
As process of sputtering of polyurethane foam is carried out
Having ordered in firm of the corresponding profile work on warming of the building polyurethane foam, you stipulate convenient time to which there comes the minibus with all necessary equipment. To ensure functioning of the high-pressure apparatus, line voltage has to be 380 V therefore for its work usually start the generator.
Helpful advice! Pay attention that from network only devices of low pressure which provide much more poor quality of sputtering can work with voltage of 220 V.
To surface on which will evaporate polyurethane foam stretch hose through which in gun necessary components will move. At the same time all people who accept fate in work or just are nearby shall put on special protective suits and respirators. It is necessary for protection of airways against toxic evaporations and also in order to avoid hit of foam on skin.
Apply foam gradually, moving from below-up so that to avoid admissions. Because foam extends, it is necessary to watch thickness of the received layer in process of its drawing. Though It should be noted that excesses can be removed by cutting while it will be impossible to eliminate defect further. If to proceed from technology data, then thickness of layer has to be 2-3 cm, however, practically always do more – about 5 cm.
Having made the decision to warm polyurethane foam warehouse, the house or any building, the most important – to find professional specialists who will be able to render you really high-quality services. Only in this case your investments will not be vain and will be able to be repaid. At respect for all technologies and recommendations about warming of the house polyurethane foam, the price of works will not be low, but will serve at least 25 years, and it is the considerable term throughout which you will be able comfortably to live, without worrying about anything.