Silicon internal corners...

[Rich]

As above. I grout first, then when the grout is just setting off, I run a paint scrapper (gently) along all the joints that are going to be siliconed to remove the grout. Then I come back to Silicon when the grout is dry and the room clean.

 

[carole m]

I want the internal corner in my shower just grouted with bathroom grout, i hate the sight of Silicon, in many hotels in showers you never see Silicon and in many new builds i do not see Silicon, i have had Silicon in bathrooms before and it has gone mouldy and looks bad, i understand i would have to re-grout every so often. if it is the case that it is because it is an internal corner. can ti be siliconed and then grout on top so as to make all the tiling look the some.

 

[DJS]

Hi Carole, the internal corners should not be filled with grout. The gap is filled with flexible Silicon, so that it does not crack due to heat expansion. If it is filled with grout it will crack, it is not the way it should be done.

I'm not saying all contractors working on commercial projects such as hotels and new builds are bad, I have seen both excellent and some shocking examples myself.

If you are having problems with mould growth, then you need to ensure your background is prepared properly, use suitable grout protector, and a decent mould resistant Silicon (preferably matching your grout colour, so it look like a grout line). Plus using a proper cleaning product, to remove soapy residues from grout and tile surface once every few months, should all add up to keeping it looking like new.

Also, if your tiler uses a Silicon shaping tool, and cornertape/masking tape, then the Silicon joint will be nice and tidy. Not sploged in and smoothed over with a finger, which I guess is what alot of people are used to seeing. So, just because your used to seeing something done a particular way, doesn't mean it is the right way to do it!!

Good Luck

 

[diamondtiling]

HI Carole and welcome to Tilersforums. All good advice from DJS, you do need Silicon rather than grout in the internal corners. Just get a quality brand and someone who can apply it properly. Silicon turns black and unsightly because of soaps and bodyfats during showers etc
and showers are always worse than baths for these types of problems.

 

[Rich]

I agree with both the guys above and I doubt you will find anybody on here that will say we are wrong. I really couldnt count how many rooms I have put right after thousands of pounds worth of damage has been done to the house just because the "tiler mad2" didnt know or couldnt be bothereds to use Silicon.

It is not that we like to use Silicon, it would be a lot easier and quicker just to grout the joints in but it WILL fail and water will destroy the wall and floor behind the tiling.

As has been said above, a neat Silicon joint that has been done by a pro will blend in with the rest of the room, a bad messy joint done by a monkey will look awful.

 

[jubba]

Hi Carole, the internal corners should not be filled with grout. The gap is filled with flexible Silicon, so that it does not crack due to heat expansion. If it is filled with grout it will crack, it is not the way it should be done.

All makes sense about using Silicon in the corners.

So when you fix the tiles should a deliberate gap be left (use spacers) in the corner rather then butting the tiles together?

 

[Rich]

All makes sense about using Silicon in the corners.

So when you fix the tiles should a deliberate gap be left (use spacers) in the corner rather then butting the tiles together?

Yes, I use wedges and leave about 2mm

 

[FreeD]

I alway use a flexible grout, and grout everything, then Silicon when grout is dry.

 

[jubba]

Would the same expansion gap be left when tiling down to bath, to leave a void to fill with Silicon?

Or should the tiles actually rest on the edges of the bath then Silicon across the joint?

 

[hillhead]

Jubba and FreeD, leave a gap down the internal corner 2mm minimum.
Do not use flexible grout then silicon over.
Grout all walls leaving the vertical corners clear of grout.
When grout dry and any cleaning off done silicon the corners with a colour to match the grout.

 

[hillhead]

Would the same expansion gap be left when tiling down to bath, to leave a void to fill with Silicon?

Or should the tiles actually rest on the edges of the bath then Silicon across the joint?

Yes jubba, leave again about 2mm along bath and fill gap when grout is dry.

 

[Rich]

As above, if you grout then Silicon over the top, the grout will tend to crack and come loose and take the Silicon away with it over time.

 

[RichieHall]

I'm just about to do a similar job, so let me just recap the above advice to make sure I understand,

For an internal corner I would need to leave a gap between the wall and tile of the tile depth (+ Adhesive) plus about 3mm on both walls, leaving a 3mm diagonal gap between the two tiled walls, then fill the gap with Silicon?

 

[JMW]

I'm just about to do a similar job, so let me just recap the above advice to make sure I understand,

For an internal corner I would need to leave a gap between the wall and tile of the tile depth (+ Adhesive) plus about 3mm on both walls, leaving a 3mm diagonal gap between the two tiled walls, then fill the gap with Silicon?

Spot On.

 

[Mike]

I'm just about to do a similar job, so let me just recap the above advice to make sure I understand,

For an internal corner I would need to leave a gap between the wall and tile of the tile depth (+ Adhesive) plus about 3mm on both walls, leaving a 3mm diagonal gap between the two tiled walls, then fill the gap with Silicon?

i'm trying to understand your post, when tiling the first wall into the corner, leave a gap of 2/3 mm for expansion. when tiling the second wall into the same corner leave a gap of 2mm between the 2 tiles again for expansion. rake out any grout from the expansion joint prior to siliconing