Wedi, Devi and Tiles over ply

[andy63]

I am currently refitting the home bathroom using 300x600 large format porcelain tiles using Mapei adhesive and grout.

I have done most of the wall tiles and having done a fair bit of research just wanted to know if I have missed anything in the spec for the floor build up which I am due to start (area about 4m2).

I have removed the existing floorboards and screw fixed 18mm ply to joists at 150mm crs including all edges. I have also added some extra noggins to support the ply edges and where the bath will go..
The joists were all over the place so I had to level them with ply shims before laying the floor,
even so we still have a slight shallow in one corner.

Next Wedi board over the floor then a devimat then the tiles on top of that.

My questions are:
1. Should I use a SLC to level the ply before laying the wedi?
2. Do I need to bed the wedi in keraquick to the ply as well as screw fixing with wedi washers?
3. Mapei advise bedding the devimat in keraquick/ latex and laying the tiles in the same mix – do I do this in one go or wait for it to go off over the mat first before laying the tiles?

Thanks in advance for your help

cheers

 

[DHTiling]

Sounds ok to me...i would use a SLC over the devi to protect the mat as you tile and it will also level any indulations you have...

Mapei fibre plan is excellent for this type of application.

Just to add, make sure any gaps around the perimeter are siliconed to prevent SLC from levelling your ceiling...:smilewinkgrin:

 

[andy63]

Thanks Dave

Would that be Fiberplan with latex over the devi?

Also would you recommend adhesive bedding the wedi to the floor as well as screwfixing?

cheers