Backer rod

[Android 07]

I am re-doing the silicone on my bathtub and upon removing the silicone, I have seen cracked or missing grout/filler behind the area where the silicone used to be.

After doing some research, it transpires that grout is non waterproof and should not have been there in the first place. So, I now intend to chisel away the grout and then squeeze in a backing rod and then apply silicone on top.

The problem is I cannot find backing rods in Screwfix/Toolstation or B&Q. Can anyone post links if it is called something else by these places?

 

[jj4091]

Grout is moisture proof although not completely waterproof, you can however get grout sealer which makes it waterproof rather than chiseling it out.

 

[tell80]

Silicone is typically used between the rim of the fixture and the bottom edge of the last row of tiles - best practice is using it at vertical inside corners as well.

On the tub rim push back the grout you mention, and dry & clean off the rim.
Then apply the silicone bead, keeping the nozzle inside the "crack" - squeeze until the silicone is just proud of the tile face.
Then use a soapy finger to compress and make good the silicone.

 

[Alastairreid]

 

[Harry Bloomfield]

The problem is I cannot find backing rods in Screwfix/Toolstation or B&Q. Can anyone post links if it is called something else by these places?

Have you considered alternatives to exposed silicone sealant? I used white plastic quadrant mouldings around our bath, intended for use by double glazing installation. it comes in two sizes, is stupid cheap, very easy to fit and stays clean. All I did was cut to size, apply sealant to both faces and press into place, then remove the excess silicone. https://www.eurocell.co.uk/ stock it, as no doubt will other suppliers.

 

[tell80]

Android 07,

With respect to the above poster,

Please dont use any kind of custom seals on fixture rims. Stay with silicone.
There's all kinds of seals, & methods of sealing on offer - basically they are fitted pre-tiling or post-tiling.
Sooner rather than later most fail - they often lift which allows mould & slime to collect, eventually allowing penetrating water up behind the tile, and down the wall.
Keeping them clean and dealing with them after failure can be a nuisance.

 

[Android 07]

I have chiselled off the already cracked/mouldy grout.

I will post a pic to show where I stand.

 

[Android 07]

 

[freddiemercurystwin]

Why do you need to use a backer rod anyway? I can't see why one would need to be used in this situation.

 

[Android 07]

Why do you need to use a backer rod anyway? I can't see why one would need to be used in this situation.

There is half an inch gap between the tub and the wall and there is also the gap between the tile and the tub. This was previously filled by grout ( I think ) . The silicone sat on top of it.
Now, do I use tile adhesive grout or Easifill filler and then silicone on top ?

 

[Harry Bloomfield]

There is half an inch gap between the tub and the wall and there is also the gap between the tile and the tub.

Which was why I suggested the quadrant moulding - it will hide and seal all of that neatly.

That looks like a metal bath, is it?

 

[freddiemercurystwin]

OK, the gap doesn't really look that big in the pics but anyway, there's nothing wrong with a big silicone seal it'll just take longer to go off and will take some more skill to make sure it looks good, you can use a backer rod if you really want to then I guess to prevent wasting silicone and it just being squeezed down the gap, the silicone quadrant just needs to lap onto the bath and the bottom of the tile by a mm or so. There are a few threads no here about getting a good seal around the bath which would be worth searching for, meticulous cleaning beforehand, some masking tape to get a perfect line on the tiles and bath, fill the bath beforehand, good quality silicone and a wet finger.

Personally in the first instance I'd also steer clear of any quadrant stuck on the front.

 

[Android 07]

Which was why I suggested the quadrant moulding - it will hide and seal all of that neatly.

That looks like a metal bath, is it?

No, definitely not.

 

[Harry Bloomfield]

Personally in the first instance I'd also steer clear of any quadrant stuck on the front.

Each to their own, but I hate to see lashings of silicone sealer and it quickly goes black. Quadrant strip never goes black and not visible silicon, it can just simply be wiped down with a cloth.

3M do make a strip for the job, which comes in a roll. It hinges down the middle and is flexible with sealant on the back. Half sticks to the wall, the other to the bath. It works, is a step up from silicone and a lot tidier, but in time it does deteriorate in colour. The quadrant is cheaper, permanent and tidier.

 

[Harry Bloomfield]

No, definitely not.

Then as above - what ever you settle on doing, it needs to be done with bath filled with water.