Help on underfloor heating and tiling

[xdrive]

Hi

I'm going to be tiling my kitchen. It's suspended floor. Has been laid with plywood.

There are small gaps between the Plysheets and also the wall (expansion gap)

What do you use to fill seems before screeding?

I will prime Plysheets, place under floor heating mars, then. Screed. Prime again apply flexible adhesive and tile.

Is this correct order.

Thanks.

 

[xdrive]

Any tilers out there?