Underfloor Heating

[Nabal]

Hello all, long time lurker here. Just was wondering if anyone would be kind enough to give me some advice?

I am getting a double extension built and we are at the point of getting quotes from builders. We have been looking at underfloor heating (UFH) downstairs (25 sqaure meters) and so far we have had a mixed response depending on who we ask....

One builder is very pro water UFH, he says it is better at heating the whole room and is more economical than electric UFH.

Another builder does not like water UFH, and says that electric UFH is very economical to run at 0.5pence per square metre per day!

Having done some research it does appear that water can cope with lower temperatures better, however electric does seem to reach temperature faster. The cost implications etc. are becoming a little confusing...

We currently have a condensing boiler and know we will need a manifold, so it is not like we have to put in a new boiler or anything.
can anyone help unravel this for me?

 

[mointainwalker]

One builder is very pro water UFH, he says it is better at heating the whole room and is more economical than electric UFH.

Fits in with what I generally hear. Do a search on electric UFH ( possibly also in the Electric forum) and I think comments will be similar.

Having done some research it does appear that water can cope with lower temperatures better, however electric does seem to reach temperature faster

Possibility you are not comparing like for like. Water UFH is generally laid in a screed 50 - 70 mm thick which acts as a thermal store and slowly releases the heat.



Electric is nearly always laid directly under the floor suface, usually as a retro-fit, and consequently has much less mass to heat. This means it both heats up and cools down quicker than UFG in a heavy screed.

Whichever you choose, ensure you have good, thick insulation beneath system to minimise heat-loss into slab and ground.