Cost of UFH

[volcane]

Hi All,

 

We are at the stage of laying underfloor heating prior to concrete pour. The quotes coming back are mad,

 

I want to know how much I should expect to pay to design the layout, supply the pipe and manifold and fit. I know it should be possible to DIY it but I'm not really able to. I have planned to go with a Sunamp stack plus a split ASHP to provide the heat source.

 

We have a large area but have a low heat requirement, I had hoped that the contractor would purchase the pipe and lay it without too much fuss

 

 

thanks

[Dudda]

What area is the house as that depends a lot on cost and how well is it insulated will determine how much pipe you need? A medium or poor insulated house will need more pipes and they'll be closer together (100mm or 150mm) while a super insulated house can have the pipes further apart (eg 200mm).

 

Putting in the UFH myself was one of the easiest parts I've done. You need to spend the first hour working out where things will go and planning it to make it easy (eg mark out kitchen units). You can put down the pipe yourself and get a plumber later to connect up the manifold and system making less work. You don't have to do it all yourself. If you go to a company like Wunda (which I used) they'll design the layout for you but most companies supplying the underfloor heating will design a layout I think. It's not much work when you use a programme (LoopCAD I think it's called and you can probably use the free trial). Post the design here the software or company proposes and the members here will suggest further improvements to the design they've got from experience. 

 

 

[Alexphd1]

First off send your plans off to some companies ie wunda, uponor, speedfit etc they will supply you back a spec (but not drawings most companies will keep hold of these until you actually buy their products). Then its easy for you to price up the material but remember a lot of material is interchangeable with other material, I used uponor mlcp (not pex!!) pipe but bought manifolds off ebay and still havent made up mind on the controls. 

 

[ragg987]

3 hours ago, volcane said:

I had hoped that the contractor would purchase the pipe and lay it without too much fuss

It will probably be cheaper, and definitely much quicker, to have a specialist (e.g. liquid screed company) lay the perimeter insulation, membrane and UFH pipes to the manifold rather than your builder who has not done it that often. Ours took less than a day (210m2) including screed pour.

2 hours ago, Dudda said:

... while a super insulated house can have the pipes further apart (eg 200mm).

ASHP runs most efficiently if you can reduce flow temperature. Pipe spacing is an important factor. This link suggests a 5C increase in flow temperature at 200mm vs 100mm spacing: http://johncantorheatpumps.blogspot.co.uk/2014/03/getting-best-from-underfloor-heating.html