BUILDING ENVELOPE


Insulating a better future


uentin assieu o Huntsman uilding olutions eplains why minimising air leakage must go hand in hand with better insulation


cynene H oam ite spray applied insulation rom Huntsman uilding olutions


pray applied insulation eectively seals the comple voids in a uilding structure


High performance insulation,


B


etter insulation of domestic households is seen as one of the most important ways of reducing carbon emissions and slowing the effects of climate change. A recent environmental audit select committee report says that 19 million UK homes are poorly insulated and that unless urgent action is taken to improve energy eficiency o homes, the  will fail to meet its climate targets. nortunately, as over  o our


current housing stoc was uilt pre when little thought was given to heat-loss prevention, the challenge is significant verall, roughly  o  caron emissions are generated through heat- ing, hot water and cooing in domestic properties. Even more troubling was the act that in , emissions rom uildings actually rose y  over those of the previous year.


BASIC PRINCIPLES


 we go ac to asic principles, heat loss in a building occurs through a com- ination o our processes conduction,


mar/apr 2022


convection, radiation and mass transer he colder the outside temperature, the warmer the inside, and the worse the thermal insulation of the building en- velope, the greater the heat loss will e n the , the construction industry focuses primarily on U values – some- times referred to as heat transfer coeficients  as a measure o conduc- tive heat loss. These are used to measure how effective elements of a building’s fabric are at insulating against heat loss. The lower the U-value of an element of a uildings aric, the more slowly heat is ale to transmit through it, and so the better it performs as an insulator. ery roadly, the lower the value, the less energy is required to maintain com- fortable conditions inside the building. nortunately, measuring the ther- mal eficiency o a structure y value alone fails to take into account heat loss through air leakage. If you spend any time in high mountain environments you quickly realise that it is the wind that strips the heat from your body. And it is the same in buildings. It doesn’t matter


effective control of air movement and air quality, in combination with low carbon heating are interconnected elements that need to be addressed as one in the design of new-build housing to


ensure heat loss mitigation


what your U-value is if there are draughts. Traditional forms of insulation are


relatively ineficient in preventing air leakage through draughts. They can’t completely fill the comple voids and cracks in roof structures or seal the interface between the insulation and the building components. They can also struggle to cope with small structural movements which can lead to air gaps. hen  o a uildings heat loss is caused y air leaage, an insulation


www.sbhonline.co.uk 51


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84