Is it worth putting on underfloor heating on existing floor?

maryg2017

6 years ago

We are refurbishing an existing house and the cost of digging up will be very expensive, and have been advised to lay heating above the existing concrete floor. Has anyone done this, and would you recommend it? Is it still efficient?

Many thanks!

Comments (2)

PRO
Dale Loth Architects
6 years ago
The simple answer is that adding underfloor heating over an existing concrete floor is usually impractical. Perhaps whoever advised you to lay heating above yours knows of some unusual circumstances making this viable.

You must have insulation immediately below underfloor heating for it to work properly - usually 75mm if the floor currently is uninsulated. Therefore, the floor level will rise, affecting doorways, etc.. With relatively inexpensive-to-fit electric underfloor heating, the build-up above the insulation can be small, but running costs are normally prohibitively high. More expensive-to-fit but economic-to-run, normally gas-fired underfloor heating in plastic piping requires additional height and is normally laid in a 65mm min. sand / cement screed.
PRO
CKL Consulting
5 years ago
There are thin underfloor heating systems that can be used in a retrofit situation. When designing an economical ufh system certain factors do need to be considered e.g. Age of property - ceiling heights - threshold heights - u value of property to establish heat losses from ufh system. If you have a set of plans and contact number happy to discuss further. Email karen@cklbuildgroup.co.uk CKL specialise in the more unusual and retrofit ufh at stems and have not only a wealth of experience in this sector but portfolio projects that have used similar systems.

Do not use electric underfloor heating unless you have some way of operating this system directly from renewable energy sources. On going running costs are extremely high.
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Is it worth putting on underfloor heating on existing floor?

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Dale Loth Architects

CKL Consulting

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