Fitting large shower tray.

[sprite1275]

Hi. Fitting a 1500x800 thin shower tray upstairs on floorboards. What's the best way to go about it? Has to be risen up as the joists are in the way to lay flat to the floor.

Would you batten it with 3x2 then a sheet of 18mm ply?
Or use the riser legs it comes with but they just screw round the outside of the tray. Surely the middle needs to be supported?

Also do most bed them on a bed of 18mm morter ontop of the ply?

 

[Mr Chibs]

I had a large low profile shower tray laid, on plywood, then solid mortar bed. Mine was touching three walls, and it made it difficult to lay onto the mortar bed... I used flat ratchet straps to lower down and then slide them out when down, a little level and tap down, all was good. Tray was 70Kg.

Just be aware your floor height will be higher, you might have to fashion a threshold etc.

Think some use tile adhesive, but I can't comment. Presume yours is stone resin?

 

[Wayners]

Watch skillbulder on youtube. Covers trays following manufacturers advise.
Also covers the problems some have

 

[sprite1275]

I had a large low profile shower tray laid, on plywood, then solid mortar bed. Mine was touching three walls, and it made it difficult to lay onto the mortar bed... I used flat ratchet straps to lower down and then slide them out when down, a little level and tap down, all was good. Tray was 70Kg.

Just be aware your floor height will be higher, you might have to fashion a threshold etc.

Think some use tile adhesive, but I can't comment. Presume yours is stone resin?

Yes stone resin. Surprised it has bolt holes at the edges for the riser kit but nothing for the middle. Was thinking of glueing 18mm ply to the bottom of it then resting it on 3x2. Also use the riser legs to level it.
Or cold make a plinth with the 3x2 and ply then do what you did on top.

Did you use marine ply?

 

[Mr Chibs]

No I just used 'normal' ply, sorry can't help with riser, as mine is just sat on mortar bed.

It feels like a concrete floor when you are in it.

 

[Madrab]

Never use the riser legs, they always cause problems longer term, always build a plinth and level that off, baton size usually dictated by the trap clearance required and then top it with at least 18mm WBP ply or OSB3. Then tank the wet space.

 

[sprite1275]

Cheers folks. Made plinth osb3 and sat it on bed of mortar. Just don't feel right putting mortar on ply. Just feel like the mortar will crack to dust over time with natural wood movement. I must be wrong though as it's what the manufacturer instructions say .