# Is it OK to insulate on top of existing ceramic wall tiles?



## chandler48 (Jun 5, 2017)

OK, I'll try to picture you putting insulation on top of tiles. It may take a minute..............Nope, won't work. Insulation goes in the stud bays behind your wall covering, whether it be backer board or sheetrock or lath/plaster. It just doesn't go on top of anything.


----------



## Andy-C (Jul 18, 2017)

Hi Chandler48,

I'm talking about insulated plasterboard, which is typically fixed (pinned or glued) to block/brick walls.

So I suppose that my question is really about whether there are reasons (moisture problems, etc.) why the plasterboard should not be pinned to the wall through the tiles - a cross-section of the wall would be:
|block|tile|insulation|plasterboard|

Must the tiles be removed before the insulated plasterboard is fitted to the wall... if so, why?

Thanks!


----------



## chandler48 (Jun 5, 2017)

More information is always helpful, like wall design. Normal walls are final outer covering-Tyvek-OSB-framing(with insulation), vapor barrier-final interior wall. So what you have is different.

Can you link us to the "plasterboard" you are referring to? If the tile are substantially adhered to the block, then removing them won't be of a concern, as they will act as an extension of the block. What are your plans for electrical? Where are you located?


----------



## Andy-C (Jul 18, 2017)

I live in Ireland, where concrete block is the norm for house construction. The external walls of the house are 9" cavity blocks, with a plaster render on the outside. The internal side of the wall is plastered and tiled with ceramic tiles. The tiles are pretty sound, and well adhered to the plaster on the blockwork.

Here's a link to commonly used insulated plasterboard
http://www.xtratherm.com/wp-content...cations/Xtratherm_UK_Drylining_Guide_11_3.pdf

I understand what you say about the tiles just being an extension of the blockwork, but the tiles and grout essentially form a moisture barrier, so I'm wondering what this does to the dew point of the wall, and any other related factors.

I haven't considered any electrical issues yet.

Thanks!


----------



## Nealtw (Jun 22, 2017)

I think you will be fine.


----------



## Andy-C (Jul 18, 2017)

Hi Nealtw,

Care to elaborate on how/why it'll be fine?

Thanks!


----------



## chandler48 (Jun 5, 2017)

I believe Neal and I are thinking alike, although he may correct me. You don't have to worry more about moisture on the tile any more than you would with the block behind them. No more moisture will be available to the tiles than is available to the block, so by being a solid extension of the block, you should be fine. I saw no where in the link where there was an R value placed on these panels. Or I missed it. 

Your construction methods are vastly different than those in North America, so getting direct information from the manufacturer is a good thing.


----------



## Nealtw (Jun 22, 2017)

Mold is what you would worry about in a wall structure.
Mold needs air moisture and food. I don't see a problem with anything in the wall 

Not sure how they seal to the floor but allowing dust air and moisture there would be a possibility.


----------

