Travertine in a bathroom - preparation

[johnfrench10]

Hi

I've been looking everywhere for advice about tiling with travertine in a bathroom and the more I read the more confused I get.

I want to put travertine in a bathroom, floor to ceiling on the walls and also on the floor.

My plan for the walls is:
1. Remove the existing plasterboard on the stud walls and replace with a backer board, possibly nomoreply or hardibacker.
2. Fix backer board to the outside wall which is brick and plaster skimmed, the backer board will be screwed to the block and fixed with adhesive
I think I am fairly happy with this approach for the walls.

For the floor I am not so sure. The subfloor is wooden joist with 18 mm chipboard tongue and groove. I want to put travertine tiles with electric underfloor heating in.

I know i have to screw down the chipboard to the joints securely as they currently creak but I am not sure about what to put on top. Do I need 12 mm ply and 12 mm backer board or can I just use backer board screwed down and with adhesive? I don't want the tiles to crack but don't want to raise the level of the floor loads either to get it stiff enough. I am using Mapei flexible adhesive for the tiles from Tile Giant.

Thanks very much.
John

[Phil Hobson]

Hi John, I would remove the 18mm chipboard, replace with 18mm exterior ply. Then over board with a cement backer board (James Hardie) or the like, glued and screwed. You should be fine with wall prep. Hope this helps

[johnfrench10]

Phil

Thanks the quick reply. The existing 18 mm chipboard goes under the walls on each side of the room so not sure how much of this I can remove. If I cut it at the walls the joins won't be on a joist which I want to avoid. If it turns out I can't remove the chipboard, can you suggest a back-up plan?

Thanks

[Phil Hobson]

If you have no issues with floor height, you could overlay the chipboard whith min 15mm ply then glue and screw Hardie board. ( may be a good idea to brace joists with extra noggins)

[Dave]

Phil

Thanks the quick reply. The existing 18 mm chipboard goes under the walls on each side of the room so not sure how much of this I can remove. If I cut it at the walls the joins won't be on a joist which I want to avoid. If it turns out I can't remove the chipboard, can you suggest a back-up plan?

Thanks

You can cut it back to the walls and then add noggins to strengthen any area's unsupported at the edges..

Pky has more structural strength than chipboard but will need noggings
at approx 300mm intervals.