Floor insulation

[powerdesal]

Back to the old perennial questions about insulation.

SWMBO is complaining that the tiled floor is far to cold, I can go along with that.

My thoughts are that, as we will be retiling the whole downstairs, on top of a perfectly good but naff coloured existing tiled floor, we should lay some insulation. My idea is to use the very high density pu foam sheets that are available in the brico sheds, usually pink I seem to remember. They slot together in a 'tongue-and-groove' sort of way and are available in various thicknesses.

I can afford to lose some room height but not a mega lot so wondered about laying (say) 18 / 20mm thick insulation and directly laying the new tiles (40 x 40) on top with the usual tile waterproof tile cement etc. I anticipate I would lose about 35mm on height which is doable from the doors point of view.

Any thoughts / comments from the builders?????

[Théière]

[quote user="powerdesal"]Back to the old perennial questions about insulation.

SWMBO is complaining that the tiled floor is far to cold, I can go along with that.

[/quote]

Tell her to get up off the floor [;-)]

[Le Plombier]

You need to lay a cement or concrete screed on top of the insulation or your tiles will break up in no time

Le Plombier

[Théière]

You could get away with Marmox board and flex adhesive and grout, it's what the foam shower bases are made from.

[powerdesal]

[quote user="Le Plombier"]

You need to lay a cement or concrete screed on top of the insulation or your tiles will break up in no time

Le Plombier

[/quote]

Therein lies the problem.

A screed would need to be at least 75mm and I honestly dont think I can lose that much height. The ceiling height is not a problem, I could lose 200 + mm but the doorways....................

[powerdesal]

[quote user="teapot"]You could get away with Marmox board and flex adhesive and grout, it's what the foam shower bases are made from.[/quote]

Having just quickly googled Marmox, they seem VERY interesting. 2.7 at 10mm sounds good. Are they available in France?. Bet they are not cheap!!!

[Théière]

Steve, take a look in Lapeyre, they have the insulation boards you need for tiling on (Marmox)

[Le Plombier]

I lay a lot of floor insulation, for underfloor heating

No matter how level the surface you lay the insulation sheets on there is always slight movement on the insulation panels and the tiled floor on top will crack

This is why the insulation always has a screed on top

There is a system which I have seen. sold by Point P and manufactured by the principal plasterboard manufacturer in France

It consists of lightweight polystyrene granules with sheets of placo type material laid on top, all bonded and glued which is suitable for a variety of finishes including tiling. Good insulation and would meet your depth critera for the floor

Cannot remember the name but if you have a local Point P builders merchant go and talk to them, they have a brochure on plasterboard and associated materials and the details are in there

Le Plombier

[Théière]

Le Plombier, I appreciate what your saying and the reasons behind it.  I have tiled many wet room floors without any problems using Marmox boards, I was very dubious the first time the architect asked me to do it.  With the correct adhesive and grout we have had no problems.

The boards I think you are talking about are the hardibacker type which are very good too.

 

[mike151]

i layed tanalised battens at 450mm centres & put30mm dense polystyrene in between over some nasty 1930's grey tiles, then floor boarded over them with proper floor boards. looks great & is warm, lost about 50mm floor height but was putting in new fire place Door & skirts so it didn't matter.battens would have been better thicker because i had to hammer my nails in at an angle to get some bite.

[LEO]

[quote user="mike151"]i layed tanalised battens at 450mm centres & put30mm dense polystyrene in between over some nasty 1930's grey tiles, then floor boarded over them with proper floor boards. looks great & is warm, lost about 50mm floor height but was putting in new fire place Door & skirts so it didn't matter.battens would have been better thicker because i had to hammer my nails in at an angle to get some bite.

[/quote]

In principle I agree with Mike151, a timber floor is the way forward.

Why introduce a cold surface - ie. - tiles.

Tiles may be prudent in Spain or Greece but , not in France!

[D53]

As mike said

or screw  3/4 ply sheets down then lay ]

Option 1 wooden floor or laminalte floor on top

Option 2 use flexable adhesive and tile

Option 3  screw hardibacker on top of 3/4 ply use normal adhesive and tile

 

3/4 ply will be a good insulator and very stable for any of the above

[WJT]

Powerdesal, we are doing the same when we finally get to our living room and kitchen downstairs. I agree with what has been said about tiled floors being cold and would like to use something like the product in the link below. This sort of thing is only 2.5mm thick and the insulation board is 3mm. Therefore, a total of only 5.5mm. I assume that both would need a layer of screed over though. 

We have radiators so it wouldn't be our main source of heat but just used to take the chill of the tiles.We can't afford too much height so was hoping we could get away with as thin a screed as possible. I love wooden floors but it would not be practical in this area and would like perhaps terra cotta.

http://cgi.ebay.co.uk/Devimat-Underfloor-Heating-Mat-12-0m-Concrete-Floor_W0QQitemZ350124072892QQihZ022QQcategoryZ20598QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

http://cgi.ebay.co.uk/Underfloor-Thermal-Insulation-Tiles-5-sq-m-3mm-Thick_W0QQitemZ350133611508QQihZ022QQcategoryZ20604QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

[Théière]

I agree with you WJT, almost the looky likey of Marmox (just a brand name).  Not sure about 3mm board, go thicker if you can otherwise you will be heating the sub floor tiles too.

Better than Ply which will eventually get damp through, probably 20% moisture in the boards the day they are delivererd and does not have the same insulation properties, basically the old way of doing it.

Some more information from a company doing similar, although probably not as cheap as Ebay [:)] http://www.ebeco.com/en/index.php

 

[Chancer]

Carpet? [6]

I'll get me coat!.................

I think we are on the same wavelength preffering the look of a tiled floor but not liking the cold at the moment, if you dont have enough depth for a screed then you cant use underflor heating which would be the ultimate solution, if the room is not too big could you consider using the underloor electrical heating? I know it will be relatively expensive to run (but dont forget the price of electricity is cheap and stable here) but it would only need to take the chill off during these cold snaps in addition to your normal heating. A friend used it as the sole heating in their tiled conservatory and they are very pleased with it.

Getting back to carpet, I use the horrible cheap and cheerfull Brico-depot carpet as sound and heat insulation under laminate flooring, it is more effective and far cheaper than the wafer thin ondulene or polyester stuff they try and rob you for, the best thing is when some locals thought that I was using the laminate or parquet to protect "the lovely carpet" à la toile cirée, would it not have been cheaper to use a roll of plastic[:)].

[D53]

[quote user="WJT"]

Powerdesal, we are doing the same when we finally get to our living room and kitchen downstairs. I agree with what has been said about tiled floors being cold and would like to use something like the product in the link below. This sort of thing is only 2.5mm thick and the insulation board is 3mm. Therefore, a total of only 5.5mm. I assume that both would need a layer of screed over though. 

We have radiators so it wouldn't be our main source of heat but just used to take the chill of the tiles.We can't afford too much height so was hoping we could get away with as thin a screed as possible. I love wooden floors but it would not be practical in this area and would like perhaps terra cotta.

http://cgi.ebay.co.uk/Devimat-Underfloor-Heating-Mat-12-0m-Concrete-Floor_W0QQitemZ350124072892QQihZ022QQcategoryZ20598QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

http://cgi.ebay.co.uk/Underfloor-Thermal-Insulation-Tiles-5-sq-m-3mm-Thick_W0QQitemZ350133611508QQihZ022QQcategoryZ20604QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

[/quote]

 

you wont need scread,but when working out the cost will also need a probe which is laid the same time as the mat and thermostat,use flexable adhesive for the tiles.

[powerdesal]

[quote user="WJT"]

Powerdesal, we are doing the same when we finally get to our living room and kitchen downstairs. I agree with what has been said about tiled floors being cold and would like to use something like the product in the link below. This sort of thing is only 2.5mm thick and the insulation board is 3mm. Therefore, a total of only 5.5mm. I assume that both would need a layer of screed over though. 

We have radiators so it wouldn't be our main source of heat but just used to take the chill of the tiles.We can't afford too much height so was hoping we could get away with as thin a screed as possible. I love wooden floors but it would not be practical in this area and would like perhaps terra cotta.

http://cgi.ebay.co.uk/Devimat-Underfloor-Heating-Mat-12-0m-Concrete-Floor_W0QQitemZ350124072892QQihZ022QQcategoryZ20598QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

http://cgi.ebay.co.uk/Underfloor-Thermal-Insulation-Tiles-5-sq-m-3mm-Thick_W0QQitemZ350133611508QQihZ022QQcategoryZ20604QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

[/quote]

I wonder if the floor tiles at the second link are like these;-

http://www.castorama.fr/store/polystyrene-extrude-20-mm--1-25-x-0-60-m-PPRDm952463.htm

If they are, the cost differential is substantial. UK 5.288 / m sqr and Casto euro 3 / m sqr

The Casto one is thicker too.

The inference from the Castorama link is that no screed is required.

I just finished a conversation with SWMBO and got seriously shot down after suggesting that the retiling should be changed to an insulated wood (or wood -effect) floor. [:(]

[Théière]

Hi Steve, from the look of the castorama ones, they do not have the strong stabilising faces on their exterior. That's probably why Le Plombier (hope he is not upset by my comment) was stating the need for a screed coat.

Marmox and similar have faces for tiling on directly (that should save time money and thickness of the screed).

Why did you ask SWMBO, brave man, she already told you she wants tiles. [:D]

[WJT]

Teapot, I think I will print that for my husband.[:)]

From what I gather, if we do use this underfloor matting then it wouldn't be necessary to screed over it. However, I wasn't thinking of putting it everywhere because it wouldn't be a main source of heat. For example I thought we would mainly put it in the centre of the seating area not along the edges or under the furniture. They do recommend doing this in bathrooms, they say not to put it under the bath etc.. Therefore, this would make the floor uneven.

Powerdesal, sorry to complicate your thread. [:$] Let us know what you do in the end, I would be very interested.

[powerdesal]

[quote user="teapot"]

Hi Steve, from the look of the castorama ones, they do not have the strong stabilising faces on their exterior. That's probably why Le Plombier (hope he is not upset by my comment) was stating the need for a screed coat.

Marmox and similar have faces for tiling on directly (that should save time money and thickness of the screed).

Why did you ask SWMBO, brave man, she already told you she wants tiles. [:D]

[/quote]

I agree they do not seem to be coated but the accompanying text implies that they are good insulation under ciment, carrolage (sp) or bois. not ciment + carr... (sod it - tiles ), hence the inpression that they can be tiled over directly.

I asked because:-

a. I am 4000+ miles away and hence untouchable.

b. She is usually sensible.

c. The opening shots of a campaign to change her mind.

ps the fact that we have already bought the 90 sqr m of tiles might be an issue.

[Théière]

[quote user="powerdesal"][quote user="teapot"][/quote]

I agree they do not seem to be coated but the accompanying text implies that they are good insulation under ciment, carrolage (sp) or bois. not ciment + carr... (sod it - tiles ), hence the inpression that they can be tiled over directly. Flexible tile adhesive is usually loaded with polymers so sticks very well to anything, I would be tempted to try a small piece first before commiting to the whole project.


ps the fact that we have already bought the 90 sqr m of tiles might be an issue.
[/quote]

Yep that's usually how I lose too [:D]

[BIG MAC]

[quote user="WJT"]

Teapot, I think I will print that for my husband.[:)]

From what I gather, if we do use this underfloor matting then it wouldn't be necessary to screed over it. However, I wasn't thinking of putting it everywhere because it wouldn't be a main source of heat. For example I thought we would mainly put it in the centre of the seating area not along the edges or under the furniture. They do recommend doing this in bathrooms, they say not to put it under the bath etc.. Therefore, this would make the floor uneven.

Powerdesal, sorry to complicate your thread. [:$] Let us know what you do in the end, I would be very interested.

[/quote]

Simply lay the sheets where you want them then in the areas with a point loading (Under baths for instance) bring them up to the same height with screed, ply or laytex depending on thickness of insulating board and substrate. Job Jobbed.