Water damage to bathroom wall fibre board

Many bathrooms repaired or renovated by Advance Shower Repair have old asbestos, Blue Board or fibro cement cladding as their wall coverings underneath the tiles. Those materials deteriorate over time due to capillaric water damage, causing mould and tile damage.

What causes it, and how can it be prevented?

Here’s a typical example. In some bathrooms from the 70’s and 80’s, a copper tray was installed as shower waterproofing. Then 8mm asbestos, 6mm Blue Board or 4.5 mm fibro cement sheeting was either nailed or screwed to the batts. A cementous screed was layed out as the shower floor, and the floor waste was soldered to the waterproofing copper tray. So far so good.

But the lower edge of the shower wall sheeting was covered by up to 30mm by the screed, and later exposed to the edge of the tiles on the shower floor and walls. In those days an adequate sealant was not applied between wall-to-wall or wall-to-floor shower joints. Instead, stiff grouting or plain sand / cement mix grout was used.

The result? Over the years, water will seep through those shower joints and enter the cavities behind the tiles, soaking the cladding. Fibro cement and similar materials are made of layers that disintegrate rapidly when exposed to water. This results in bathroom mould, rot and the tiles loosening or even falling off – causing a danger to you and your family.
How to prevent water damage to your shower walls

In our experience it is much better to screed the shower floor first, then install the cladding as the next step. Most importantly, a bondbreaker bead should be applied between any two shower walls and wall-to-floor joints, before the waterprooofing is carried out. Adequate curing time for the materials used should also be allowed for.

A freshly repaired and resealed shower

This is Advance Shower Repair’s practice when carrying out Sydney bathroom renovations or shower repairs. This technique will permanently stop water from entering your bathroom substructure, preventing bathroom water damage and providing a long lasting shower for years to come.

Note: Please take special care when removing and disposing of asbestos materials!

Leave a comment