Sizing Calculations

Calculating the size of woodburner required to heat a space accurately is complicated and is usually left to those capable of calculating heat losses.

However, for those satisfied with an approximate size, follow these steps:

For properties that do not comply with the Part 'L' Building Regulations (pre 1995)

1. Calculate the volume of the room by multiplying length x width x height in metres, then multiply by 50
2. For rooms facing North, add 15%
3. For French windows, add 20%
4. If there is double glazing, deduct 10%
5. For very exposed properties, high altitude and windswept, add 10%
6. This will give you the heat output requirement in Watts

For properties that comply with the Part 'L' Building Regulations

1. Calculate the volume of the room by multiplying length x width x height in metres, then multiply by 22
2. There is no need to deduct or take into allowance for North facing or the fabric of the building
3. This will give you the heat output requirement in Watts