underfloor heating mats

[Brocky101]

aying underfloor heating mats in my log cabin.

I have 120mm tounge & Grove boards with 10mm insulation boards fixed down with insulation board washers.
I have taped the joints with gaffa/duck tape and used 15mm expansion tape around the sides to allow for wood expansion on the self leveling compound.

Anyway my question: Do I need to cover the metal washers with silicone or something as I don't know if any conductive materials will have any adverse effects on the heater mats/element.

Also I was told to cover the insulation boards with a foil sheet to improve heat transfer upwards but again will this have adverse effects on the mats/element.

Hope someone can help, cheers.

Untitled

• Brocky101
• 20 Feb 2015
• 2

 

[stillp]

What do the instructions for the UFH say?

 

[Brocky101]

What do the instructions for the UFH say?

Not a lot really, certainly nothing about insulation boards.

 

[stillp]

The manufacturers are the only people competent to answer. Anyone else will just be guessing.

 

[Steve]

aying underfloor heating mats in my log cabin.

why? Just fit electric heaters they'll be far quicker to warm up And possibly cheaper to run as a result.

 

[Brocky101]

aying underfloor heating mats in my log cabin.

why? Just fit electric heaters they'll be far quicker to warm up And possibly cheaper to run as a result.

Oh ok I didn't think of that !! I'll just send the underfloor heating mats back and rip up the insulation boards I've just fitted. Thanks.

 

[ericmark]

Normally the element is held by the glue or cement used to hold it all in place but there a number of different types. Some are made to length, some come as sections and can be cut at set points and still another type can be cut to any length and uses a chemical which is to an extent self regulating.

So to control again normally it uses a two sensors one in the floor and one air the floor one limits the heat of the floor so you can walk on it and the other of course the temperature of the room.

There is normally very good instructions on where sensors must go and how it should be laid.

Again depending on type it could cause the wood to go on fire if not correctly laid.

So the first answer is correct you need to ask the manufacturer.

 

[ban-all-sheds]

aying underfloor heating mats in my log cabin.

When it's all done, and you've gone through next winter, it would be good if you can remember this topic and come back and tell us if it actually works, i.e. does actually heat the interior of the log cabin OK, not just make the floor warm.

I have 120mm tounge & Grove boards with 10mm insulation boards fixed down with insulation board washers.

Surely 10mm of insulation is utterly pointless?

Also I was told to cover the insulation boards with a foil sheet to improve heat transfer upwards but again will this have adverse effects on the mats/element.

You've got to have a vapour control layer somewhere - could you post a drawing showing the overall construction from the bearer timbers up to the finished surface? (BTW - I hope your chosen flooring will come up easily when the heating mats start to fail.)

Have you done the calculations on how much heat you will need to put into the cabin, what that translates to in w/m² from the floor, and whether that will be achievable given the floor surface temperature and its radiant properties?

 

[ericmark]

I was caught out I had heard how good the system was and it was fitted in a wet room.

The tile has a maximum heat 27°C is normally considered as the maximum and to get a room to 20°C with just 7 degrees differential is hard. You need zero loses so air change will have to be with a heat recovery unit.

So covering has to be a good conductor and black normal is black tiles. See This report on use of wood it would seem in real terms wood covering on under floor heating is out.

I have found only one good use for underfloor heating. The 18W one foot square sample heating tile keeps my beer to exactly the right temperature to brew.

But that 18W per square foot is a good indexation. So for a 8 x 10 room maximum heat around 1.5kW add furniture that drops so average output is more like 700W which can heat the room but it would need very good insulation.