Hi,
We have a terrace with tiles where the grout has cracked and water risks seeping down to the neighbor living below. The tiles were laid in the spring of 2010, and after the first winter, the grout has cracked and large pieces are coming loose. Could it be that the builders used bathroom grout?
Do we have to break it up and lay new grout?
Grateful for any answers!
We have a terrace with tiles where the grout has cracked and water risks seeping down to the neighbor living below. The tiles were laid in the spring of 2010, and after the first winter, the grout has cracked and large pieces are coming loose. Could it be that the builders used bathroom grout?
Do we have to break it up and lay new grout?
Grateful for any answers!
Well, I have read about it now as well.
Then I suppose they are more of an aesthetic issue, it looks quite bad as it is now. The building is alive and moving, especially when they are building the "city-tunnel" under the city, but all the seals are cracked and come off if you pick at them a little.
Question 1) Could it be bathroom sealant that was used and doesn't withstand freezing temperatures?
Question 2) Do you break it up and redo it, or can you apply new sealant on top (what do the standards/regulations say)?
Then I suppose they are more of an aesthetic issue, it looks quite bad as it is now. The building is alive and moving, especially when they are building the "city-tunnel" under the city, but all the seals are cracked and come off if you pick at them a little.
Question 1) Could it be bathroom sealant that was used and doesn't withstand freezing temperatures?
Question 2) Do you break it up and redo it, or can you apply new sealant on top (what do the standards/regulations say)?
You always apply the grout last, after the tiles have been set with the adhesive, so if it needs to be redone, you can scrape away the grout in all the joints and then apply new grout. The question is just how long it will last if everything keeps moving. It's possible that the freezing temperatures combined with water in the grout have led to the damage, but if the substrate is moving and flexing, that could also be the cause of the cracks.
Thank you Taken,
What I meant was that it might be a crack, a length if it was about movement in the building. Since the joint is equally bad everywhere, I rather think that there might have been water in the joint and freezing temperatures that have caused it to flake today.
Good point!
Good point also that you put the joint last anyway. Then it will probably be easier to chip away the old joint and apply a new one.
What I meant was that it might be a crack, a length if it was about movement in the building. Since the joint is equally bad everywhere, I rather think that there might have been water in the joint and freezing temperatures that have caused it to flake today.
Good point!
Good point also that you put the joint last anyway. Then it will probably be easier to chip away the old joint and apply a new one.
Well, rubber mat was a bit misleading, more like a film, not sure what it can be called but it was black on one side and gray on the other side, which they then put some kind of glue on top of. Rigid as it did not cause movement. Must have been the temperature that caused all the joints to crumble apart.
Unsure about what the film was about, didn't see all stages of the setup. But regardless, I don't think it caused the joint failure.
The question is, is this common? Does it happen that sometimes there is water left in the mixture that then cracks when it freezes? Should one use silicone-based joint outdoors? The one currently present is like adhesive, meaning like concrete, and crumbles apart. Shouldn't it be more elastic?
The question is, is this common? Does it happen that sometimes there is water left in the mixture that then cracks when it freezes? Should one use silicone-based joint outdoors? The one currently present is like adhesive, meaning like concrete, and crumbles apart. Shouldn't it be more elastic?
The grout does somewhat absorb water when it comes onto the surface, and this then dries over time (same thing in bathrooms), and if it's wet when frost comes, I can very well understand if it cracks. The same also applies to the tiles, you need to have frost-resistant tiles if you are going to use them in an application like yours. However, I don't know how the grout is usually handled when doing such work for outdoor use in subzero temperatures, but someone here surely knows about it 
Thank you Taken,
Yes, that actually sounds like a natural explanation. That the joint lets through some water and simply breaks if it freezes before it dries up.
The tiles are frost-resistant, we were careful to check that. But the problem with the joint should have been known before. This must have happened earlier. There must be a joint that withstands outdoor use?!!
Yes, that actually sounds like a natural explanation. That the joint lets through some water and simply breaks if it freezes before it dries up.
The tiles are frost-resistant, we were careful to check that. But the problem with the joint should have been known before. This must have happened earlier. There must be a joint that withstands outdoor use?!!
ANSWER:
I have talked to several tile setters now;
It is not uncommon to use the same grout in the bathroom as on the patio, provided it is a good grout, a good brand should withstand outdoor climate. So, the fine/expensive/good brands should handle this, apparently. All grouts let through some water, the good ones withstand freezing temperatures, bad ones (like mine) or old ones (+5 - 10 years) may crack. Then you need to use a "fog kratsa" to scrape out the grout (remove the old one without touching/damaging the waterproofing). It is enough to remove half so that you can apply new on top, as it is mainly about appearance rather than function.
I have talked to several tile setters now;
It is not uncommon to use the same grout in the bathroom as on the patio, provided it is a good grout, a good brand should withstand outdoor climate. So, the fine/expensive/good brands should handle this, apparently. All grouts let through some water, the good ones withstand freezing temperatures, bad ones (like mine) or old ones (+5 - 10 years) may crack. Then you need to use a "fog kratsa" to scrape out the grout (remove the old one without touching/damaging the waterproofing). It is enough to remove half so that you can apply new on top, as it is mainly about appearance rather than function.