Underlay & Carpets for UFH

Troy McClure

Has anyone good experience of buying and using carpets and underlay for underfloor heating from Geothermal.?
I can find a couple of underlays with a tog value of 0.8 and carpets vary with the lowest about 1.1tog.
I am led to believe that you want to stay below a combined tog rating of 2.5 for GUFH.
I visited Des Kelly's and a carpetright and they simply had no idea what I was talking about. It was so bad that in Des Kelly's I showed a guy on the back of one of his carpets the tog rating. Alot of carpets dont even show this. The guy just told me how long he worked in carpets and had never seen that before!
Any advise and pointers on this most welcome especially that keeps the costs down, and please dont tell me how unsuitable you may think carpet is to UFH.

Outkast_IRE

Troy McClure wrote: »

Has anyone good experience of buying and using carpets and underlay for underfloor heating from Geothermal.?
I can find a couple of underlays with a tog value of 0.8 and carpets vary with the lowest about 1.1tog.
I am led to believe that you want to stay below a combined tog rating of 2.5 for GUFH.
I visited Des Kelly's and a carpetright and they simply had no idea what I was talking about. It was so bad that in Des Kelly's I showed a guy on the back of one of his carpets the tog rating. Alot of carpets dont even show this. The guy just told me how long he worked in carpets and had never seen that before!
Any advise and pointers on this most welcome especially that keeps the costs down, and please dont tell me how unsuitable you may think carpet is to UFH.

Look if you have to get carpet (i would wholeheartedly be against it)

Your on the right road, just get the lowest tog ratings you can within reason especially with regards to the underlay. To the best of my knowledge there is no special carpet etc available.

Basically the higher the TOG the longer you will be waiting to be able to feel the heat in the room, and it will probably have a longer cool down period too .

Troy McClure

Thanks
Is there any place to go that are clued into this issue? Or any particular brand that have a range that cater for UFH needs.

I found an underlay called everspring that has a tog value of .8 that seems quiet thick to me to have such a low value. But I guess these rating are accurate.

NickTellis

http://www.carpet-underlay-shop.co.uk/underfloor-heating-underlay-30-c.asp

Shame on Des Kelly...

bigalk

as stated above the lower the TOG rating you can get to the better (TOG of underlay and carpet combined). There are indeed specialist UFH underlays available out there, but there seems to be a hefty dose of snake oil involved around the TOG figures, especially when it comes to wood underlay for UFH.

For example - I am forever seeing sites that sell a wood flooring underlay with a TOG of 1. They will class this as "suitable for underlfoor heating". Then, in the same paragrah, go on to say something like "provides heat insulation" or "good thermal insulation properties", which is totally at odds with UFH. So which is it, a UFH underlay or an insulating underlay - it cant be both.

From my seat (im industry related) your Underlay should never go above 1 TOG for a carpet underlay, or 0.5 TOG for a wood flooring underlay. Low TOG underlays for carpet can get expensive, but with wood flooring there is no reason (be that budget or otherwise) that the underlay should be over 0.5 TOG. There are many low cost low TOG wood flooring underlays on the market.

bigalk

there are specialist underlays available for underflor heating for carpet. Google "Everspring Eclipse" for one example - it comes in at 0.8 TOG