Bedding low profile stone resin capped shower tray on plinth

[bojitbond2000]

I'm about to install a 40mm, stone resin quadrant shower tray on a wood plinth and 18mm exterior plywood. My shower tray instructions say to bed the tray on a sand / cement mix but doesn't go into any detail.

Firstly, can anyone tell me if this needs to be a wet or dry mix? Also, would I need to prime the plywood with something to prevent it sucking any moisture out of mortar mix? I'm sure the mortar would just crumble without the plywood being primed. Any suggestions as to what product to use to prime it?

Also, how on earth am I going to put the shower tray onto the bed of mortar and get it level? Is there a tried and tested way of doing this? Sounds like I need a crane

Many thanks.

 

[oilboffin]

There's no black art to doing this use good plywood 18mill I use exterior grade then prime it with waterproofer then wet mix mortar 4-1 about 1inch thick put the tray on it and push it down then use a level get it flat by pushing down once it's level leave it for a day you should have no probes all the very best good luck

 

[bojitbond2000]

Thanks for the info, can you suggest a product to waterproof the plywood? Its 18mm exterior grade. I've got some plasterboard primer for tiling, should I use that or is there a specific waterproofer for plywood?

Many thanks

 

[joe-90]

Any old primer will do. Make sure you get it DEAD LEVEL or your shower doors will never work properly.