You could remove the cementitious grout from the grout joints remove the grout in the shower pan floor to wall horizontal transitions and remove the grout in the inside corners of the wall tile.
Leaking tile shower walls.
This is usually cause by water spraying from the leak in back of the wall.
If you have a leak anywhere you will know beforeit gets tiled.
Tile shower leaks in walls if applicable if your shower water leak hasn t revealed itself with the above tests then it s entirely possible that water is leaking out through the tile on the shower walls.
The once the joints are open and clean use an astm c920 silione sealant and fill all of those joints.
The longer the leak has gone unnoticed the larger the repair will be.
Starting low on the wall splash or spray water on an isolated area and keep checking for leaks as you work your way up a couple of feet at a time.
Failure to do so puts more moisture behind the wall or under the floor which can cause mold rot in the wood structure or crumbling drywall.
If your tile shower is leaking the cause of the leak must be found and addressed as soon as possible and definitely before you take a shower again.
The first is faulty installation of the tile and the second reason is that the tub may have settled.
Determine where your shower is leaking.
Leaky tiles can occur anywhere where water is used whether it s a shower a wet room or a kitchen splashback.
In modern construction shower tile is generally installed with a moisture barrier under a base of waterproof cement board so water damage is somewhat less likely.
One other sign of a shower leak behind the wall is the drywall tile in front of the valve becomes spongy.
If your shower leaks behind wall most times you can t tell from the front side of the shower.
If the water is lower than the mark then you have a shower leaking somewhere.
In older homes ceramic shower tile was often installed directly over drywall.
Leaks typically start along the bottom of the wall where the tile meets the top of the tub or shower pan.
They can often cause damp and mould within surfaces behind tiles and can even threaten the structural integrity of walls so it s important to tackle the issue at the first sign of a leak.
If the shower drains and there is no leak then you will need to examine whether the leak is coming from missing grout between tiles on the shower walls.
Water damage happens quite often on tiled shower and bath walls especially in older homes.
The bathroom is where much of the water in your house is used making a leak in the bathroom tile a very urgent matter.
Apart from a plumbing problem there are two main reasons tile will leak.
Those areas are exposed to the most water so damage tends to spread quickly.
With the drain plugged the water has nowhere to go unless there s holes or penetrations in the liner.
These walls are susceptible to water damage if the tile s grout joints develop gaps.
When the tub is filled with water or there is weight in the tub it can cause the tile beneath it to flex and compress and cause the tub to settle.
The first step to repair shower tile after a leak is to assess the damage to determine how much of the wall has gotten wet.
Water getting behind tiles can also damage the tile adhesive which could cause tiles to come loose and possibly fall off the wall altogether.