What board best under shower tray?

[yartin]

Hi
What to put under shower tray? Floor boards will be removed, I need to put something on the joist to support shower tray. I have read 18mm treated ply wood is used a lot. But my installer is suggesting Aqua panel boards, I looked online and they're used for walls before tiling and 50kg per m2 is max weight, am I looking at the wrong aqua boards?

It will be done in March so am preparing parts etc.
Shower try size will be 900mm X 1200mm , still not purchased.

Thanks

 

[Burnerman]

I’d go for OSB, but both materials are ok but ply especially mustn’t get wet.
Ensure any ends are supported on noggins or whatever as any deflection must be avoided.
John

 

[foxhole]

Aqua panel is ideal , the weight mentioned is for wall tiles , not flooring .Under compression it’s nearly indestructible .
What type of tray ?

 

[yartin]

Aqua panel is ideal , the weight mentioned is for wall tiles , not flooring .Under compression it’s nearly indestructible .
What type of tray ?

duh

 

[freddiemercurystwin]

Aquapanel alone will not be sufficient to support a shower tray, plywood would be OK. Or if you are tiling the floor then if funds permit I would go belt an braces with plywood sub-base, then 6mm aquapanel then tiles, no need to aquapanel under the shower.

Hardiebacker board is an alternative equivalent product to aquapanel, there may be other brands, just google them.

OSB has no place anywhere near a bathroom.

 

[yartin]

Is this the Aquapanel?

Knauf AQUAPANEL® Floor Tile Underlay - 6mm x 900mm x 1.2m | Wickes.co.uk

Knauf AQUAPANEL® Floor Tile Underlay - 6mm x 900mm x 1.2m

www.wickes.co.uk

 

[freddiemercurystwin]

yes

 

[yartin]

.duh.

 

[Mike13]

Aquapanel is brittle, it will need support between the joists, with ply for instance.

 

[yartin]

Aquapanel is brittle, it will need support between the joists, with ply for instance.

That's exactly what I thought, it's made of cement can easily crack between joists, specially with 1000mm plus long span shower trays, they may survive with small shower trays.
What is used for support between joist?
I believe best option is an 18mm marine plywood (or treated plywood) screwed directly over joists for a 900mm X 1200mm shower tray.

 

[Burnerman]

The reason for me considering OSB......picture this scenario, although different from yours!
Imagine two pitched roofs, draining down onto a leaded gulley, maybe one foot wide and with a gentle fall to a hopper head.
I was all set to use exterior grade ply beneath the code 4, but the building inspector insisted on OSB claiming that the ply was anything but waterproof and would delaminate if it got wet....so OSB it was.
Either way, either timber board would be fine, but mustn’t get wet so it’s up to you with the silicone!
Any ends should be supported with noggins that can span the joists so there is no deflection.
Good luck with your project......ensure you can access the shower drain easily if possible and solvent weld drain is best.
John

 

[yartin]

In the pic below, black are joists, blue is shower tray plus plywood/OSB. What timber do I use for the brown?

I guess fix 2 battens on the sides of the joists then plywood/OSB sheet screwed to the battens?

 

[Burnerman]

Just glue and screw bearers on the sides of the joists, keeping them level with the top of the joists so they can bear the weight. Treated softwood will be fine.
Will the tray drain be accommodated ok?
John

 

[yartin]

I am looking now to buy shower tray & enclosure, few questions please:
1. Any recommended manufacturer? I've been told Mira, any others?
2. I am going for 1200x1000, can I buy tray and enclosure separately of different makes?

 

[Burnerman]

I have been very satisfied with the Mira Flight series trays......stone resin with a quality capping and they come with a quality outlet.
They must be installed completely flat and on a medium that gives a cushion - the rep said that a thick bead of silicone was fine. Check if the outlet position suits you!
I don’t like the leg riser kits, and prefer a timber plinth if I need it raised.
As for an enclosure, buy the best you can afford - mine all came from Screwfix, delivery direct from the manufacturer.
John