Typically it is reckoned you lose 13-15% heat through the floor. With a suspended timber floor, it’s equally or even more important than wall insulation to prevent draughts coming up through the floor. We offer a solution using a breathable membrane taped at overlaps and the perimeter of the room for airtightness.
The importance of floor insulation
A suspended timber floor tends to be cold and draughty because of the air circulating beneath it. Rooms with voids underneath, such as bedrooms over garages, or rooms over cellars, are especially prone to draughts. Filling and sealing the gaps between the floorboards goes part way to eliminating the cold air, but for maximum thermal efficiency installing natural fibre underfloor insulation is a must.
Where there is no void under the room insulating a timber floor requires pulling up the existing floor covering and boards, installing airtight membrane and insulation between the floor joists and relaying new floor covering. This is clearly very disruptive to household life and quite expensive, so it is a job that is best tackled when other building work, such as re-plastering, or removing internal walls is taking place. However, if there is a cellar below giving access, the project is much easier and more cost effective.