Three indicators that you've got a shower leak
Look for the following signs:
Presence of mould or mildew in the bathroom, especially around the shower
Water stains on the ceiling directly below the shower
Paint that is peeling or flaking
These are all tell-tale signs that there is a leak that needs to be fixed. This is when identification of the source becomes a priority. It could be a really straightforward issue, such as shower doors not being closed in the correct manner, so when you are looking for reasons for your leaking shower, it’s always best to start with the basics.
The First Steps to Take
It's essential to make sure that your shower door is not closed incorrectly, or that there is an ill-fitting shower curtain or shower screen, as both of these can be the cause of water related problems.
To check this:
Splash water against the closed glass, or the drawn curtain, and check to see if any water shows up outside the shower. If your shower curtain is not doing the job it should, you may want to think about fitting a shower screen.
If you have rubber edgings on your shower screen or doors then any wearing can lead to gaps appearing, so you should check to see if any water is present outside the shower in this area.
Check any areas of caulking around the bottom of the shower where it is attached to the wall. It is possible that the caulking can break and crack with age and leaks can occur.
If either the rubber on your shower doors or the caulking is causing the problem, good news - you can easily replace the rubber shower seal at the bottom of the glass with a new one.
If however, after splashing water in the shower you cannot identify any obvious leak, you will need to take further action.
Spray water around the shower
In order to check the entire shower area for obvious signs of leaking, you should stand inside the shower, to put the same amount of pressure on it that is there when you believe the leakage is happening.
Begin by spraying at the bottom of the shower, where the panelling meets the shower tray, and work your way up the walls, checking for any water exiting the shower as you go.
One common problem that you may identify with this process is the hollow shower profile filling up with water. This usually happens because the area around the shower screen has been sealed; this should not be the case. If this sealing takes place then the profile or frame is unable to leak into the shower tray as it fills up, and it simply overflows.
The solution to this is to unseal around the screen so that the water can leak into the shower tray.
If spraying the water around the shower does not reveal any obvious leaks, you should check the shower tray in more detail.
Testing the shower tray
One of the most common places for a leak to occur is in the shower tray; the base of the shower. It’s possible that there may be crack in the grouting, an unintentional gap between the shower tray and the wall, or a problem with sloping.
If the leak is in the shower tray then it saves you taking time testing the drain, so checking the shower tray first makes good sense. You need time to thoroughly check the shower tray, so you need to choose a day when you are going to be in the house the whole time. Then you need to follow these steps.
Make sure the shower drain is completely water tight. You can do this using plenty of duct tape.
Use a bucket or other method to fill the shower pan from a source other than the shower head. Obviously, if you use the shower head this negates your ability to isolate the shower tray as a potential leak location.
Once the shower tray contains approximately one inch of water you will need to watch for signs of water around the shower and on the ceiling below.
It’s important to note that if the leak is relatively small it may take several hours for any signs of water to become visible. This is why you need to give yourself plenty of time in the house to check for the leak.
If water becomes visible, and it is evident the problem is with the shower tray, you can take temporary measures by applying some masonry sealant around the tray. It should be noted though that this is not guaranteed to be successful, and in the long run you will probably need to call in a plumber to successfully re-fit the shower tray.
Checking the shower drain for leaks
It’s not uncommon for leaks to occur around the drain in your shower; this is especially likely if you have a plastic of fibreglass shower, as when you put pressure on the shower by standing in it, you can break the seal around the drain.
There are a couple of ways you can check your shower drain to identify if a leak is present, both of which involve the same basic process.
If you have access to the underneath of the shower drain then you should plug the drain completely with a rag and switch on the water. Watch the underside of the drain and see if any water is coming though. If it is then you know that there is a leak around the drain.
If you don’t have access to the underside of the shower drain then you need to use the same method, but slightly differently. Again you need to plug the drain with a rag, and switch on the water. This time you should let a puddle form in the shower tray and mark the edge of it with a bottle of shower gel, or another available item. Watch to see if the puddle diminishes in size. If it does then you know there is a leak around the drain.
Fixing a drain leak can be simple if you have access to the area underneath the shower, you may just have to tighten the nut that locks the drain in place. If this doesn’t work then you will probably have to replace the drain assembly. If you do not have any access to the underside of the shower via a panel, you may have to gain access through the ceiling below. This is a more complicated task, and you may want to hire a professional pair of hands.