Air Tightness

Air tightness in buildings has become an issue due to los of energy through gaps in the fabric of the building which is being caused by windows, doors, bad workmanship or bad design. The direction of regulations is going towards a value of uncontrolled air changes in a building of 2M3/M2 of floor area per hour at an air pressure of 50pascal.

In order to maintain a healthy living space, we need fresh air and the concept behind making a building airtight is to introduce controlled methods that give us the amount of fresh air that we need. This can equate to approx. 20% of the air being replace each hour - this being done with air directly from the outside environment which means this air has to be heated to the require temperature. However, if a heat recovery system is installed, this will fall to below 4%, dependant upon the fabric U-value and the air tightness.

Fabric first with IJM

IJM Timber Frame Carbon Footprint


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With our wide range of experience and knowledge, IJM are happy to design and build any timber products you may desire