Hi all, my pool builder has just finished a conversion of our pool from pebblecrete to tiles.
The result is great except for one 'detail' that isn't a detail in my book. The grout between the porcelain mosaic tiles is cement colour grey which is a relatively light shade of grout.
For our coping we chose bluestone which has been grouted with dark grout. The grouting of the coping was done after the grouting of the rest of the pool had long been done.
I already had concerns, when the grouting was being done for the coping, that there was too much residue left behind on the pool tiles but the pool builder told me it would all work out and to leave everything alone as he doesn't like owners getting involved in his work and messing things up which I can understand.
However, on final delivery day when they did the big clean-up and handed over the keys so to speak, turns out the dark coping grout has effectively stuck to the lighter grout of the pool tiles as I had been afraid of...
This was their last working day before heading into the Christmas break so the earliest they can do something about this is after the holidays. Of course, we'd like to fill up the pool and actually use our pool during the break. Given that we hired the pool builder back in July with the express intent of getting the pool finished before the middle of November, I'm a bit annoyed at the moment to say the least.
So my questions are:
- Given that the cement colour grout between the pool tiles turns darker when wet anyway, will this problem go away/blend in (at least for the parts under water) or will it still be visible when you're in the pool that there's different shades of grout under water? Knowing this will at least allow me to determine whether I can already fill the pool up or not.
- He's suggested coming back after the break to put some light acid on the groutlines and give them a scrub for the ones above the waterline. Will I have to drain the pool to allow that to happen? Or is this something that can safely go into the water and that I just need to rebalance the chemicals of the water afterwards?
- Will the suggested solution even work? I mean it's not that the light cement grout is dirty. It's just received an additional layer of darker grout basically... My concern is that no amount of cleaning is gonna resolve this. Cleaning dark grout is basically still just going to result in clean, but still dark, grout... I'm afraid only a mechanical removal of the top layer of the grout where the dark grout has stuck is going to resolve this. Am I correct in thinking this?
I've actually just gone over a dark groutline with a bit of sandpaper and that seems to do the trick. Problem is that doing this is going to take forever so we'll definitely be in the pool for the holidays, just working our asses of on hands and feet for something that shouldn't have happened in the first place and not in any water with a cocktail in hand
- Or could a viable alternative be to apply an additional 'coat' of the lighter cement colour grout over the dark one... Problem there I assume would be that if the groutline is full then you can't really add more.
- Additionally, the bluestone hasn't been sealed yet and the grout has only been applied to the groutlines, not the full tiles, so now the coping looks super streaky as well. He's told me, since I need to get a different guy to come and do the sealing (to which he's provided a contact), that that person will be able to fix that issue.... Not convinced that he will though unless if he grouts the entire tile which is something my wife was trying to avoid as she likes the lighter shade of bluestone.




The result is great except for one 'detail' that isn't a detail in my book. The grout between the porcelain mosaic tiles is cement colour grey which is a relatively light shade of grout.
For our coping we chose bluestone which has been grouted with dark grout. The grouting of the coping was done after the grouting of the rest of the pool had long been done.
I already had concerns, when the grouting was being done for the coping, that there was too much residue left behind on the pool tiles but the pool builder told me it would all work out and to leave everything alone as he doesn't like owners getting involved in his work and messing things up which I can understand.
However, on final delivery day when they did the big clean-up and handed over the keys so to speak, turns out the dark coping grout has effectively stuck to the lighter grout of the pool tiles as I had been afraid of...
This was their last working day before heading into the Christmas break so the earliest they can do something about this is after the holidays. Of course, we'd like to fill up the pool and actually use our pool during the break. Given that we hired the pool builder back in July with the express intent of getting the pool finished before the middle of November, I'm a bit annoyed at the moment to say the least.
So my questions are:
- Given that the cement colour grout between the pool tiles turns darker when wet anyway, will this problem go away/blend in (at least for the parts under water) or will it still be visible when you're in the pool that there's different shades of grout under water? Knowing this will at least allow me to determine whether I can already fill the pool up or not.
- He's suggested coming back after the break to put some light acid on the groutlines and give them a scrub for the ones above the waterline. Will I have to drain the pool to allow that to happen? Or is this something that can safely go into the water and that I just need to rebalance the chemicals of the water afterwards?
- Will the suggested solution even work? I mean it's not that the light cement grout is dirty. It's just received an additional layer of darker grout basically... My concern is that no amount of cleaning is gonna resolve this. Cleaning dark grout is basically still just going to result in clean, but still dark, grout... I'm afraid only a mechanical removal of the top layer of the grout where the dark grout has stuck is going to resolve this. Am I correct in thinking this?
I've actually just gone over a dark groutline with a bit of sandpaper and that seems to do the trick. Problem is that doing this is going to take forever so we'll definitely be in the pool for the holidays, just working our asses of on hands and feet for something that shouldn't have happened in the first place and not in any water with a cocktail in hand

- Or could a viable alternative be to apply an additional 'coat' of the lighter cement colour grout over the dark one... Problem there I assume would be that if the groutline is full then you can't really add more.
- Additionally, the bluestone hasn't been sealed yet and the grout has only been applied to the groutlines, not the full tiles, so now the coping looks super streaky as well. He's told me, since I need to get a different guy to come and do the sealing (to which he's provided a contact), that that person will be able to fix that issue.... Not convinced that he will though unless if he grouts the entire tile which is something my wife was trying to avoid as she likes the lighter shade of bluestone.




Last edited: