A musty smell indoors can also indicate a water leak.
Bathroom wall water damage.
You can detect leaks in walls by looking for key signs of water damage including peeling paint or wallpaper or patches of discoloration.
Mold on walls and baseboards.
Long term leaks can cause structural damage within your walls and can also lead to serious mold problems in the walls.
If there is a strong musty smell near a certain area of your wall there could be a water leak or mold growth behind it.
A common problem in bathrooms is soft or damaged drywall where the wall meets the shower or tub particularly near the floor.
Repairing a water damaged bathroom wall is a task that is within the capability of most seasoned diyers.
In some cases water damage may be fairly light usually caused by something as simple as water spray escaping around a faulty shower curtain.
In most cases the reason for a bathroom wall repair is water damage which is particularly common around the tub and shower area.
If you are in any doubt about making the repair yourself or if the repair is a large job then hiring a professional contractor may be the best option.
However not only does it depend on your diy skills but also the size of the repair needed.
Wall cavities affected by water damage are vulnerable to mold growth which also has a pungent musty odor.
How to fix a water damaged plaster wall beside the bathtub.