Underfloor heating retrofit

[Cocat2517]

Hi.
Thinking of getting underfloor heating fitted in a 1900 house. Has a concrete slab on earth floor (approx 50mm thick).

Can anyone give me an idea on what to expect price wise? It's for approx 71m² split in 4 rooms.

Excavation depth?
Cost of.. excavation, dpm, new concrete slab, insulation
Cost of.. heating pipes, manifold etc
Cost of.. wet screeding to finish (75mm?)

Thanks,

 

[muggles]

You'd need to dig down about a foot, and be aware that you might have little or no foundations in a house that old, in which case you might well require underpinning to prevent the house falling down as you dig.

As a result your question is too open-ended to answer sensibly, but £30k could be possible.

Alternatively look at a retrofit kit like NuHeat LoPro Max which will come in at around £10k and require no digging

 

[Cocat2517]

House falling down? Bit of a scary thought, I've just re-plastered the bathroom ceiling too!

I'll mention foundations to anyone that quotes me for the excavation work.

Is NuHeat stuff a wet system that can run off an oil combi? Want to avoid electric because of running costs, EPC ratings. Also heard electric ufh has restrictions in where you can place furniture??

 

[Cocat2517]

Just reading up.on the NuHeat lopro Max. Seems ideal for us. How does it compare to traditional wet underfloor heating though? More expensive to run?

 

[muggles]

Should be about the same as traditional pipe in screed UFH to run, has very high output as well so it's suitable for older properties. You can lay thin insulation underneath it to prevent it warming the slab up too much.

Send them your details and they'll provide you with a quote. Their customer service is excellent

 

[Cocat2517]

Thanks Muggles, very helpful.

Looking around I can pick up 6mm Prowarm Profoam boards from Wickes, £200 to cover the area. I probably have the space to double up and put 2 layers down too.

Maybe a sheet of foil insulation inbetween the two as a bonus? https://www.wickes.co.uk/Thermawrap-Radiator-Reflective-Foam-Foil-500mm-x-5m/p/151452

Will be giving them a call, thanks again.

 

[OLLIE20]

Someone tells you your house might fall down and your reply is oh no I’ve just plastered the bathroom ceiling love it are you a woman by Amy chance

 

[Cocat2517]

Someone tells you your house might fall down and your reply is oh no I’ve just plastered the bathroom ceiling love it are you a woman by Amy chance

Erm, that was kind of a joke. Are you a bit slow by Susanne chance?

 

[SFK]

Cocat
I would not put a layer of that "foil
insulation inbetween the two" because that stuff is simply foil covered bubble wrap and I would be very worried it will degrade, pop, and compress, making layers above unstable.
SFK

 

[Cocat2517]

Cocat
I would not put a layer of that "foil
insulation inbetween the two" because that stuff is simply foil covered bubble wrap and I would be very worried it will degrade, pop, and compress, making layers above unstable.
SFK

Good point, thanks. What about flat foil sheeting? Just something that'll reflect a bit of heat back?

 

[SFK]

Foil is used as a vapour barrier to stop water movement (but if not placed properly can unfortunately act as a surface where water condenses).
Metal foil reflect IR heat when visible, eg behind radiator, but metal when burried does not reflect heat, so will not provide the extra thermal insulation you are looking for.

 

[Cocat2517]

Will give it a miss altogether then.

One other consideration is boiler. Planning on a Worcester Heatslave 25/32 combi. Likely to be any compatibility issues with the NuHeat system?