How to fix torn waterproof membrane?

[cmvergara]

I am currently redoing our laundry but whoever built it did a weird job. 

I am removing the wall tiles and accidentaly torn part of waterproof membrane. I am not sure if it is waterproof membrane.

Can some please let me know how to fix this and what I need to buy from bunnings?

Thank you

[EricL]

Hello @cmvergara,

Welcome to Bunnings Workshop community. It's fantastic that you've shared your current laundry tiling project with us. We're looking forward to seeing more of your laundry project. I'm sure our community members would love to see the whole laundry once you've finished your renovation.

Thank you for posting the pictures, it really helps in determining what steps and suggestions we can recommend. Having looked at the pictures, I can't see any water proofing membrane currently attached to your wall. When water proofing membrane is applied a reinforcing mesh is usually placed in the corners and is approximately 100mm past the edge of the wall. 

Although it is not visible, you can check on that piece of tile you've taken off near the corner and see if there is any mesh attached to it. If you don't see any mesh attached, there is always the possibility that they used a moisture compliant plasterboard wall panel. If you wish to secure the wall from moisture before tiling you can use products from Crommelin or Dunlop which have a wide variety of water proofing membranes for different situations.

If you are re-plastering the wall one of the easiest waterproofing membranes to use prior to tilling is Crommelin 1L Shower Waterproofing Membrane. It's suitable for use in bathrooms and laundries. It can be tiled over with any good quality cement based tile adhesive. It's water based and does not emit solvent fumes.

It's great to be part of your renovation project, please keep us updated with your progress. I hope my suggestions help. If you have any other questions or need assistance with any other projects please post it here on Workshop.

Eric

[cmvergara]

Hi Eric,

Thanks for your help and tips. 

I checked the torn part but I don't any mesh. Do I need to put primer before painting the crommelin shower waterproofing? 

What is the best primer I can use for both crommelin waterproofing and fixing the plasterboard? 

I need to fix the torn plasterboard too. 

Cheers

Cmv

[EricL · Accepted solution]

Hi @cmvergara  ,

Thanks for your reply. Happy to help further. Let me answer your questions in order.

Once you've removed all the tiles you are replacing, you need to give the area a good clean. Please make sure to remove all tripping hazards on the floor. When handling broken tiles please make sure to use safety gloves to avoid getting cut by the edge of the tile.

Your next step is to prepare the area for plastering. You will need drop sheets for the floor and cover any furniture and appliances you don't want covered in plaster dust. This information should be helpful when it comes to plastering: How To Patch Plaster.

After the damaged area has been repaired, you can now put primer on the wall and the bare plaster. I recommend the Dulux 1L PRECISION Maximum Strength Adhesion Primer White. By putting primer on the repaired wall, it will prevent the water proofing from being absorbed into the bare plaster.

Next step is waterproofing the area. One litre of waterproofing will cover approximately one square meter. You want a strong moisture barrier with no weak spots. Please make sure to follow the instructions on the back of the can and provide enough drying time to achieve maximum barrier toughness.

When the waterproof barrier is totally dry, next step is to tile the prepared area. I recommend using Dunlop 5kg Trade Resaflex Tile Adhesive as it is an excellent rubber modified tile adhesive. The spacing of the tiles and grout colour will be up to you. This guide should be helpful if you need it: How To Tile A Splashback.

Thank you for getting back to us. We are more than happy to assist you further and I’m looking forward to seeing the finished wall.

Eric

[cmvergara]

Hi Eric,

Thanks for your help.

I am not tiling that area anymore, i will just cover it with gyprock csr 2.25 kg less mess topping compund. I will only tile the lower part where the waterproof membrane.

Cheers

Catherine