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Underfloor heating on top of an already laid concrete base

7 years ago

What type of underfloor heating could we use on top of an already laid concrete floor so as to prevent having to dig out the concrete?

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Comments (2)

PRO
Dale Loth Architects
7 years ago
Whatever type you use, you'll need to have insulation directly below the heating layer. Otherwise, much of the heat will go into the concrete slab rather than upwards where you want it. If the current slab is old and uninsulated, the problem is compounded. Gas- or oil-fired underfloor heating (warm water in continuous hose) would normally raise the floor level more than electric (cables). Electric is cheaper to install but much more expensive to run.
PRO
Floors of Stone
7 years ago
Hello helengb5,

You can use electric underfloor heating mats on top of a screed. As Dale Loth Architects have advised, insulation boards make the underfloor heating much more efficient, so would be a good idea to use.

You will have to ensure you have enough clearance for insulation boards/mats/floor covering so that you don't get any strange lips between rooms and you don't have to plane the bottom off all your doors!

Hope that helps.

Sophie // Floors of Stone
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