Leaking shower enclosures

A leaking shower can cause substantial damage to the fabric of your home. We explore some common causes of water leaks from shower enclosures and how they can be rectified.

Why do shower enclosures leak?

Shower enclosures are generally robust and reliable structures; however, to work efficiently they must be installed and, most importantly, sealed correctly.   That is not to say that faults do not occur with shower enclosures but the more common causes are associated with incorrect installation or problems with silicone sealant.

To avoid water leaks a shower enclosure must be correctly installed

For a shower door or enclosure to work correctly it must be installed in accordance with the manufacturer’s instructions.  Broadly speaking, the shower tray should be level and fully sealed to the tiles before the enclosure is installed, the sides of shower enclosure should be vertically plumb and fixed securely to tiled walls. Silicone sealant should be applied vertically on the inside and outside where the shower enclosure fixes to the tiled walls and, importantly, on the outside only where the frame of the shower enclosure sits onto the shower tray.  However, the process may differ slightly for some shower enclosures and the installation should be carried out exactly in accordance with manufacturer’s instructions.

The shower tray must be fully sealed to the tiles before the enclosure is installed

One of the most common causes of water leaks from shower enclosures is associated with the seal between the tiles and shower tray.  The walls surrounding the shower tray should be fully tiled and grouted and then sealed to the shower tray using a good quality sanitary silicone sealant, preferably containing an anti-fungal additive.  If the shower enclosure is installed before the shower tray is sealed to the tiles water that enters the frame of the enclosure can leak from the base of the wall fixing profiles into the walls.  Water leaks of this nature will often cause damp patches on the walls next to the shower tray, as puddles of water on the floor at the sides of the shower tray or as damp patches on ceilings below the shower.

In order to rectify this issue it will be necessary to completely remove the shower enclosure and the silicone sealant between the shower tray and tiles, do not be tempted to add new sealant to old as this will often fail quickly.  Once all of the silicone sealant has been removed, and the surfaces cleaned, the shower tray can be resealed and left to cure for 24 hours before re-installing the shower enclosure.

Do not apply silicone sealant to the inside of the shower enclosure at the base

For a shower enclosure to operate correctly water that enters the metal frame surrounding the glass must be able to drain from the base into the shower tray.  For this reason, unless specifically instructed to do so by the manufacturer’s installation instructions, silicone sealant should only be applied to the base of the shower enclosure on the outside where the frame meets the shower tray.  If sealant is applied to the base of the frame on the inside water may be trapped inside the frame, often causing water to leak from joints in the frame and from around the base of the glass.

Rectifying this problem may be as simple as removing any silicone sealant that has been applied to the base of the shower on the inside, taking care not to disturb or damage the seal between the shower tray and tiles.  If this does not cure the issue, or if the shower enclosure has been seated on a bed of silicone sealant, it may be necessary to remove the shower enclosure and clean away all of the silicone sealant before reinstalling in accordance with the manufacturer’s instructions.

Water leaks caused by deterioration of silicone sealant joints

Silicone sealant can deteriorate with time, losing its elasticity and adhesive properties.   When this occurs the silicone seal can become detached from the surface of the shower tray allowing water to leak into the walls, causing damp patches, or from under the shower enclosure onto the bathroom floor.  If left, water leaking into the walls can soak into the tile adhesive cause the tiles to become detached from the walls.

The solution will be to remove the shower enclosure to assess the extent of the damage.  If the problem is identified early correction may simply be a case of removing the old silicone sealant, allowing the area to dry out completely, before resealing the shower tray to the tiles.  Allow the new silicone sealant to cure for at least 24 hours before re-installing the shower enclosure.  Do not be tempted just to seal over the top of the old silicone sealant, it will not adhere correctly and will fail again quickly.

If the water leak has caused the tiles to become displaced or your suspect that the wall is very damp it will be necessary to remove the effected tiles to allow the area to dry out, which may take some time.  In this situation it is advisable to seek a professional assessment of the damage and appropriate course of action to rectify the issue.

Water leaks caused by cracked or deteriorating tile grout

Cracked or damp and deteriorated tile grout will allow water to leak from the shower into the walls behind the tiles.  Often causing damp patches and, more commonly, the tile adhesive to fail and affected tiles to become displaced.

If cracked or deteriorated grout is identified early it may be possible to remove the old grout, allow the wall to dry and simply re-grout the tiles.  However, in the majority of cases it will be necessary to remove the shower enclosure and affected tiles in order to fully assess the damage.  If you suspect that water has been leaking into the walls or floors for some time it is advisable have the problem assessed and repaired by a professional.

Preventing water leaks from shower enclosures

Most shower enclosures will require maintenance at some time, usually the renewal of the silicone sealant.  To prevent water leaks first ensure that the shower enclosure is correctly installed and sealed in accordance with the manufacturers fitting instructions.  Ensure that the shower enclosure is regularly cleaned to prevent the growth of mould, clearing away excess moisture with a squeegee after each use will also help to control moisture.  Finally, inspect the shower enclosure when it is cleaned to ensure that the rubber seals, silicone sealant and grout joints are intact and in good condition. 

In this article we have explored a few of the most common reasons why shower enclosures leak. If you suspect that your shower enclosure may be leaking act quickly, it is often worth contacting the manufacturer or the retailer first for advice regarding the problem.

If you would like some help with choosing or installing a shower enclosure please contact the experts at Room H2o or visit our showrooms at New Malden in Surrey or Wareham in Dorset.

The images of leaking shower enclosures accompanying this article have been kindly supplied by and are the property of Shower Advisor.

You may also be interested to read the following articles

Water damage on a wall caused by water leaking from behind the wall fixing profiles of an incorrectly installed shower enclosure
A shower enclosure must be carefully and correctly installed to minimise the risk of water leaks
Silicone sealant being applied to the outside of a shower enclosure
Sanitary silicone sealant being applied to the gap between the shower tray and tiles before installtion of the shower enclosure
The gap between the shower tray and tiles should be sealed with sanitary silicone sealant before the shower enclosure is installed
A water damaged ceiling caused by a leaking shower in the bathroom above
Silicone sealant applied to the base of a shower enclosure on the inside can trap water in the frame and cause it to leak
The silicone sealant around the edge of this shower tray has deteriorated and failed allowing water to leak from the shower tray into the walls