Underfloor Heating Guidelines

Below we have compiled some useful guidelines to help answer some common questions about the installation of water underfloor heating;

Flow Rate

To calculate the flow rate for each underfloor heating loop, take the loop length and divide by 40. For example, 100 m loop length/40 = 2.5 l/min flow for the underfloor heating loop.

Debris In The Pipes

If the underfloor heating system contains any debris, it should be power flushed and a “Magna Clean” added, see link below;

Adey Magna Clean Professional

Expansion Vessel Calculation

This guideline should help you to decide what expansion vessel to use, – 1000 m of pipe needs a 4l vessel. So if the underfloor heating system has 3000 m of pipe, then the underfloor heating system will need a 12l expansion vessel. This does not include feeder pipes to the manifolds or any radiators in the heating system.

Clip rail usage for underfloor heating systems are 1.5 m per sqm floor area.

Water Capacity Calculation

To calculate the water content in our underfloor heating system use 0.12l of water per m pipe. So, for example, 500 m of 16 x 2 mm underfloor heating pipework will have 0.12 x 500 = 60 l of water in the underfloor heating pipework.

For further installation information view our installation guide or get in touch to see how we can help.