Shower tray sand cement issue

[lostdiyer]

I’ve had a shower tray bedded down onto a sand-cement mixture, which is laid directly on marine plywood. I’ve noticed a small gap forming between the sand-cement layer and the plywood base.

The tray itself feels solid and stable when I stand on it, so there doesn’t seem to be any immediate issue with movement. However, I’m unsure if this gap is something typical or if it could lead to potential issues down the line?

I’ve attached a few images for reference.

 

[Madrab]

Looks like the mortar has dried out faster at the edges, possibly by the ply absorbing some of the moisture causing some shrinkage - did you prime/seal the ply first? It may be just on the outside edges being the areas that will naturally dry faster.

Though other who use Mortar to bed the tray's may be better suited to advise - I used it once and never again.

 

[lostdiyer]

Looks like the mortar has dried out faster at the edges, possibly by the ply absorbing some of the moisture causing some shrinkage - did you prime/seal the ply first? It may be just on the outside edges being the areas that will naturally dry faster.

Though other who use Mortar to bed the tray's may be better suited to advise - I used it once and never again.

Ply was sealed with SBR. I was debating tile adhesive or mortar but decided to go with manufacturer instructions - hope I don’t regret it!

 

[Koolpc]

That there is nowt to be concerned about...