Heat load first
Room heat load defines how much output the floor construction must deliver.
Underfloor heating
Underfloor Heating Design: Spacing, Circuits and EN 1264
Underfloor heating design starts with room heat load and then connects heating surface, pipe spacing, circuit lengths and hydraulics.
Short answer
Good underfloor heating design is not only about choosing a pipe spacing. It depends on room heat load, available floor area, surface temperature, supply temperature and hydraulic constraints.
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Spacing and circuit length
Pipe spacing and circuit length must fit both heat output and hydraulic limits.
System temperature
Lower supply temperatures are especially important when the system is paired with a heat pump.
Pipe spacing
Spacing controls how the output is distributed across the floor surface.
Surface output
The floor must provide enough output without pushing the surface temperature too far.
Different rooms need different layouts
Bedrooms, bathrooms, and living spaces often have different heat load and spacing needs.
FAQ
Frequently asked questions
Can I choose one pipe spacing for every room?
That is often too simple. Rooms with different heat loads and usable floor areas may need different spacing.
Why does heat load matter?
It defines the output each room needs from the floor heating system.
Is underfloor heating good for heat pumps?
It can be, because large surfaces can support lower supply temperatures when designed correctly.
Why does circuit length matter?
Long or uneven circuits make balancing harder and can limit performance.
What is the main design risk?
The main risk is sizing by spacing alone instead of by room demand and hydraulic reality.