Calculate tubing length, loop count and output for underfloor heating.
Tubing length is the area divided by spacing, with an allowance for the run back to the manifold. Loop length is capped by pressure drop, which is what determines how many manifold ports are needed. Floor covering can cut output by 40 per cent, so specifying carpet after sizing the system for tile leaves the room permanently short of heat.
Radiant Floor Heat
Tubing length = area ÷ spacing, plus an allowance for returns to the manifold
Tubing length = area ÷ spacing, plus an allowance for returns to the manifold Tubing length is the area divided by spacing, with an allowance for the run back to the manifold. Loop length is capped by pressure drop, which is what determines how many manifold ports are needed.
Floor covering can cut output by 40 per cent, so specifying carpet after sizing the system for tile leaves the room permanently short of heat.
This calculator takes 5 inputs: Heated floor area, Tube spacing, Maximum loop length, Heat output, Floor covering. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.