What material is recommended to apply in between stormwater grate and concrete slab?

[CarlL]

Hi, 

Im installing a new stormwater grate. Should I apply any tile adhesive or cement (I have GP cement and Earl's concrettemate expanding cement in my garage) in between the grate and concrete slab? or other material is recommended instead?

Please see photos attached.

[Jewelleryrescue]

Hi @CarlL 

look s like  you have a 5mm  gap under the grate to the   cement  I would just silicone it in and the outer  edges too the tiles  Gray  or  clear,

That way you can always  take it out if ever at need.

Builders liquid nails OUTDOOR  will hold strong but need  gray stuff for tile to insert join.

Some tile  glues not  water proof .  Plastic insert may not stick to cement  long.  

[JacobZ]

Hi @CarlL,

Similarly to @Jewelleryrescue, I'd suggest using silicone on the base and around the sides.

This Selleys Clear Wet Area Waterproof Silicone Sealant will be perfect for this application.

Apply a good amount of silicone to the bottom and on the walls of the rebate. Press the plastic piece into place ensuring the silicone compresses and spreads. You'll then want to run a small bead of silicone around the top edge to ensure water can't get in behind the plastic piece.

Check out How To Silicone a Gap for some further guidance.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[CarlL]

Thanks @Jewelleryrescue for your advice. Much appreciated.

[CarlL]

Thanks @JacobZ for the suggestion. Instead of applying a small bead of silicone around the top edge of the plastic piece (storm grate), what would you think if the gap between tile and plastic piece is grouted? Is this also a good practice at all?

[JacobZ]

Hi @CarlL,

Grout is not waterproof and the aim of adding the bead around the top edge is to stop water from getting in behind the plastic piece. If you did grout it, water could seep through the grout and sit under the plastic piece which can then cause mould to grow.

If you're concerned about how it looks, have a look at where the floor tiles meet the walls. There will almost certainly be a silicone join, likely in a colour to match the tiles. If you can try to match this silicone, it will look nicer than clear silicone.

This Sika 300ml Mid Grey SikaSeal Kitchen And Bathroom Silicone Sealant could be a good option which can also be used to stick the plastic piece in place instead of the clear silicone I mentioned above.

Let me know what you think.

Jacob