Some simple SAP calculations show how specifiying a wood stove for secondary and or primary heating can effect the DER (Dwelling Emission Rate). This helps the building reach the TER (Target Emission Rate), and also reduces the building's CO2 emissions.
The results of 4 SAP calculations are shown below, starting with a SAP calculation for our 'standard house'. A wood stove was then specified for secondary heating, the gas boiler was then replaced with a wood stove (but no secondary heating specified), and lastly a wood stove was specified for both primary and secondary heating.
| Primary Heating | Secondary heating | DER | CO2 t/yr |
| Gas condensing combi with a SEBUK of 88%, with heating controls of Programmer, room thermostat and TRVs | no secondary heating | 22.10 | 2.70 |
| Gas condensing combi with a SEBUK of 88%, with heating controls of Programmer, room thermostat and TRVs | 80% efficient wood stove | 20.11 | 2.57 |
| 80% efficient woodburning range cooker | no secondary heating | 8.54 | 0.78 |
| 80% efficient woodburning range cooker | 80% efficient wood stove | 6.40 | 0.78 |
As you can see very significant reductions to the DER are possible, for example specifiying a woodburning range cooker stove for primary heating reduces our 'standard' house's DER by more than 60%, and the CO2 emissions by more than 70%.
Do you want to see the documents that back up these calculations?
Wood heating not only lowers emissions, it is also a sound investment for the future....
Document L and wood stove pages:
1 - What is Doc L?
2 - CO2 emissions from fuels
3 - Effect on SAP calculations
4 - Fuel prices
5 - Consultation and installation design by experts in the field
6 - A stove is a valued feature in a house
7 - Summary