TermoFlo calculators
Four simple tools that help you make decisions about your home: which insulation to choose, how much heat the house loses, which heat source is cheapest, and what pipe diameter you need. No engineering background and no sign-up required.
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Wall insulation and dew point
Find the thermal resistance and U-value of a wall, check the insulation thickness, and see where the dew point sits so you can avoid damp and mould.
Required thermal resistance and the city's climate zone come from DBN V.2.6-31.
Building heat loss
Work out how much heat the house loses through walls, roof, floor and windows, so you can size the boiler and the radiators correctly.
Q = U·A·ΔT — heat loss through each surface, from the values you enter.
Heating cost
Compare the cost of heating with gas, a heat pump, pellets and other fuels, and find out which heat source is cheapest to run.
A comparison built from the fuel prices and source efficiencies you enter yourself.
Pipework hydraulics
Choose pipe diameters and the circulation pump for the heating system, so heat reaches every room evenly.
The Darcy–Weisbach equation: flow rate, velocity, Reynolds number, pressure drop.
What's next
We keep an open list of what we are working on. No dates — intentions only.
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