Shower Room floor

[LeeElms]

We plan on having the floor of our en-suite shower room tiled. The floor consists of 18mm tongue & groove floor boards. The person giving us a quote for this job wants to cover these with 6mm ply, and then tile on top of this.

I have 2 problems with this:

- the floor boards are quite 'bouncy' ... I am worried about the tiles or grout cracking as I can't see 6mm ply will do anything apart from providing a flat surface.

- there will be a step from the floor surface in the bedroom to the surface of the tiles, which is a trip hazard

I recall a few years ago reading on this site an approach where 18mm ply was used to fill the gaps between the joists, supported on battens fixed to the joists, and then this was covered with 12mm ply, all glued & screwed, to make a solid surface. But I can't find the post for the details.

All input (a pointer to the original post or any helpful advice) appreciated ...

 

[OLD]

How will the drain be arranged.

 

[jasonB]

As you have not mentioned wetroom I'll assume there is no floor drain needed and its just a tiled floor with standard sanitaryware.

I have used the method you mention when fitting walk in showers where ply is fixed to battens between joists and teh "tray" sits on top and is the same thickness as the rest of the subfloor - 22mm.

Depending on spans, area and size of tile you want a minimum of 12mm ply or tilebacker board if overboarding which will give you more of a step. I usually remove all the old subfloor be it square edge, T&G or chipboard and replace with 22mm flooring plywood. This is a 22mm WBP ply that comes in 8x2 sheets and is T&G grooved just like flooring chipboard. You can tile straight onto this with suitable flexi adhesives & grout. Have a look for "sprucefloor" by Wisa.

J

 

[LeeElms]

Correct ... not a wetroom.

Thanks for the confirmation and detail. I think it might have been a post you made that I was remembering.

 

[YorkshireDave]

The problem with tiling is that you have to have a vast range of experience to understand wether the floor deflection can be taomed. Deflection is what you describe as bounce. Personally I'd call the BAL technical rep or Weber technical rep in to see what they suggest. That way you are guaranteed to have a floor that, long term will not crack. I can tell you from experience that very little deflection can be ruinous!

 

[DaveyP]

Tiled bathroom floors look great in estate agents photographs but in the UK climate maybe are not the most practical of floorings.

Sure there are exceptions.. like wet rooms and underfloor heating but for the 'bog' standard en suite / bathroom there are
many other practical, good looking and cheaper methods of flooring.

But I'm concerned in the existing 'movement / bounce in the boards' if the boards are moving then the the boards need removing and the joists need looking at. (is this a loft conversion ?)