Cracks in shower floor - leaking?

[demuire]

One of my showers has a tilled floor ie little tiles with grout. Anyway, some of the grouting on the edge between the floor and the wall has come out. I had a go at regrouting these, but didn't have much luck, even though I left it to dry for more than 24 hours it didn't quite dry and it either cracked, or just washed away.

When I was cleaning the shower prior to grouting, I noticed the crack was always wet. I tried to use a cloth to dry it, but there seemed to be a never-ending supply of water in the crack! Tried to use a vacuum cleaner, tried to use a hair dryer...

Also, I've noticed that the previous owner has re-done some of the corners in silicone - is this better than grout?

How can I tell if the floor is leaking? When I go downstairs (it's a high set house), the floor and joists look dry. Is there a waterproofing membrane that is installed under the shower that is catching all the water?

Sorry if the questions are rather noob'ish, I'm new at renovation!

[mic-d]

If there is a 30-40mm step up into your bathroom it is likely that the tiles are laid on a mortar bed, or at least the shower section will be so a fall to the waste could be built in. Underneath this it's probable that a w/p membrane was installed since you see no water damage downstairs. The joint is constantly wet because there will be a reserve of water in/under the mortar and tiles that will wick up through the crack in the joint as you dry it. It may need a fortnight or more without use to dry and it really needs to be very dry before you silicone it so it will stick. It's best to use a flexible sealant at the wall/floor junction, grout will crack. You can try a waterbased product called caulk in colours that may work if you can't get the join completely dry.

Cheers
Michael

[demuire]

Thanks for that. Hmm, a fortnight without a shower sounds a bit long I guess I'll try the caulk and see how I travel...

[bricks]

caulk in colours from IMHO isnt absolutely water proof and does erode when washed with harsh chemicals- most bathroom cleaners.

Yeah you can use it to seal up the gaps but then you should put this stuff called shower seal in your shower- You can get it a reece and other plumbing supply companies ( don't know about bunnies or mitre 10).

If its done by a liscenced tradie they will guarantee it for ten years. If you follow the instructions it should work for you.

As mic said- a dry room is going to ensure the best results. Maybe wait till the weather warms up help to dry it out faster.

[Skew ChiDAMN!!]

When I was cleaning the shower prior to grouting, I noticed the crack was always wet. I tried to use a cloth to dry it, but there seemed to be a never-ending supply of water in the crack! Tried to use a vacuum cleaner, tried to use a hair dryer...

The crack being perpetually wet is a good indicator that there's moisture trapped under the tiles and trying to dry it out with a vacuum cleaner or hair drier is rather akin to trying to dry out a swimming pool by waving a japanese fan at it... you'll get there eventually if you don't develop RSI or die of old age first.

You've already discovered that it won't grout up well when wet and, frankly, you shouldn't be trying as it'll just trap the moisture under there where the odds are good it'll only cause even more problems. I suspect that Mic-D's "fortnight" is rather on the optimistic side, IMHO the quickest fix is to rip up the tiles around the affected area to expose the wet area, dry it out thoroughly and then relay the tiles... (I'm actually in the middle of doing this myself, dammit! Got exactly the same blasted problem. )

I'm sure that's not what you want to hear... no more than I wanted to see the same problem in our shower, anyway! But...

[mic-d]

IMHO the quickest fix is to rip up the tiles around the affected area to expose the wet area, dry it out thoroughly and then relay the tiles... (I'm actually in the middle of doing this myself, dammit! Got exactly the same blasted problem. )

I'm sure that's not what you want to hear... no more than I wanted to see the same problem in our shower, anyway! But...

Whooaa! Hold your horses Skew, lifting tiles? You know the tiles, even when installed correctly still let moisture through - the whole bed will be wet. That's why there's a w/p membrane underneath and why the floor grate has weep holes where the flange is w/p in.
Unless you start seeing water through the timber underneath don't worry until you can give it some down time to dry so you can get silicone to stick.

Cheers
Michael

[Skew ChiDAMN!!]

Whooaa! Hold your horses Skew, lifting tiles? You know the tiles, even when installed correctly still let moisture through - the whole bed will be wet. That's why there's a w/p membrane underneath and why the floor grate has weep holes where the flange is w/p in.

Yup, agreed... however there's a difference between damp and wet, especially when grouting. If the grout line keeps filling with water...

I also didn't say "best" way, just "quickest." I'm only talking about a couple of tiles to each side of the line, not ripping up the whole floor - enough to quickly dispose of the excess moisture within a day or two. Another couple of days to relay/grout and the job's finished within a week...

[Dirty Doogie]

Hey demuire! Is the wet patch in the floor grout line under the shower fittings? Sometimes a leaking tap spindle or body washer causes water to run down behind the wall tiles.

You say the groutline is always wet. It does take ages for these gaps to dry out and nothing I know about will set properly unless the groutline is dry. there is a clear sealant (silicone based) that sets under water but that will looky crappy.


You could try an absorbent paper towel folded into the gap - leave it for 30 minutes then put another paper towel there for another 30 minutes followed by a fan heater on low setting blowing on it all day.

Doog

[demuire]

Hi Doog. No, it's just sort of wet in al the cracks (2 of the 3 are not under the shower fittings). And yes, did the absorbent paper towel thing, but sort of gave up. Maybe I should have persevered...

[Dirty Doogie]

It takes a long time to get these cracks dry. I have used a blowtorch to do it but unless you have porcelian tiles or glass and cement based grout, I wouldnt suggest you try it.

A fan heater that blows hot air is generally the safest way to proceed. It will warm the tile and the water beneath and the air flow will evaporate free water coming to the surface fairly efficiently.

As other posts have pointed out - if water continues to get behind the tiles eventually they will start popping or lifting. It may take a year of shower use. Then you'll have to retile the base again.

Doog

[demuire]

Ended up scrubbing back all the grout with a plastic brush to make sure it was all nice and clean and remove all the broken bits, removed as much dampness as I could using some towels, got the heater fan in there and left it running for an hour or so. Seemed quite dry except for one corner which was still a little damp. Tried to dry it out as best I could...

Re-grouted all the cracks in the walls (only 2 really), and got some non-water based silicone and went around the floor/wall joint, apart from not being very good at smoothing it out I think it seems to have come up alright. Had some issues with the corner that had a bit of dampness, but it appears to have stuck.

Thanks everyone, hope what I did worked!

[bricks]

Tip for silicone joints.

If you apply the silicone to the joint, and then spray with a soapy water solution ( normal spray bottle) then smooth with your finger or a paddle pop stick, the joint will be real easy to get neat.