Heating load in Fairbanks
A home in Fairbanks has to be heated against a design temperature of −42.0 °C. That figure is measured, not modelled: it is the 1st percentile of daily minimum temperature over 30 years at Fairbanks International, 9 km away.
Design temperature
−42.0 °C
Heating degree days
6,499
Coldest month
Jan
Coldest night on record
−50.0 °C
How many kilowatts
Heating power needed at the design temperature, in kilowatts, for a detached house. Pick the row that matches the building.
| Construction | Detached | Semi-detached | Terraced | Top-floor flat | Mid-floor flat | Ground-floor flat |
|---|---|---|---|---|---|---|
| Uninsulated, single glazed | 40.0 kW | 35.0 kW | 31.1 kW | 34.1 kW | 16.6 kW | 20.4 kW |
| Unfilled cavity, early double glazing | 27.1 kW | 23.3 kW | 20.4 kW | 19.8 kW | 12.0 kW | 15.0 kW |
| Insulated to 1980s standards | 15.5 kW | 13.9 kW | 12.6 kW | 11.9 kW | 8.5 kW | 10.9 kW |
| Modern, roughly 1995-2010 | 9.5 kW | 8.7 kW | 8.0 kW | 7.7 kW | 5.8 kW | 7.0 kW |
| Current building regulations | 7.3 kW | 6.7 kW | 6.2 kW | 6.0 kW | 4.5 kW | 5.5 kW |
| Passive house | 4.3 kW | 3.9 kW | 3.6 kW | 3.4 kW | 2.3 kW | 3.1 kW |
Where the heat goes
For a 120 m2 detached house of this construction, at the design temperature.
| Element | W | Share |
|---|---|---|
| Walls | 5,093 | 33% |
| Roof | 1,488 | 10% |
| Ground floor | 1,004 | 7% |
| Windows | 2,902 | 19% |
| Thermal bridges | 852 | 6% |
| Ventilation and draughts | 4,111 | 27% |
| Heating load | 15,450 | 15.5 kW |
Calculate it for your own home
The climate half of this is measured. The building half is yours to supply.
Monthly mean temperature
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| °C | −22.2 | −17.7 | −11.7 | 1.1 | 10.6 | 16.3 | 17.2 | 13.8 | 7.5 | −3.1 | −15.2 | −20.0 |
Where these numbers come from
- Measured: the design temperature, the degree days and the monthly means. All of it from one station, Fairbanks International, over 30 complete years.
- Assumed: everything about the building. The U-values are typical published figures for each construction era, not a survey of your house. Two houses of the same age and size can differ by a factor of two.
- No credit is taken for sunshine or for the heat given off by people and appliances. That is the EN 12831 convention, because the design condition is a still, dark night.
- This is space heating only. Domestic hot water is a separate load.
- This is a calculation, not a survey. Before spending money, have the building assessed.