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How to waterproof upstairs bathroom?

Hi, long time reader first post.

Reno story-

I'm renovating my upstairs bathroom on a newly purchased townhouse- the seller (sneakily) hid some water leak/damage! it's an old brick townhouse, the room is bathroom and laundry combination. I discovered a leak behind the old laundry trough, all the way through the floor cement layer underneath and through to the ceiling of kitchen below!

They had hidden this with new carpet on stairs disguising signs of leak to the wall/stairs behind that sink wall, and with plaster/paint on the same! (I did get all the building pre purchase inspections etc, unfortunately they didn't pick this up as mustn't have been tenanted for a while, all moisture reading on walls etc/inspection was cleared!)

So due to this I've essentially gutted the bathroom, ripped up all tiles and tile cement, and the (very dodgily applied leveling cement under this). I wanted to see the extent of the damage and because of the leak wassuspicious of all waterproofing to floor and shower area.

Now I've gutted the room (I've still to clean back some plaster and tile glue), I'm looking how to best waterproof.

- I've done alot of research (and reading workshop threads) and am tossing up between villaboard vs Aqua board as base sheets, will then paint the waterproof membrane layers over, then tile on top.

What is better for shower area- aqua board or villaboard? And what waterproofing membrane would be suitable for both- I've read differing opinions of both so looking for advice please!

For ease of installation, I am looking at a shower pan to install in base of shower with above.

Have read through guides/regulations for same.

Follow up question- if go with say villa board, is it then best to use all villaboard products to ensure compatibility - ie floor sheets, primer, membrane layer etc?

Any advice is much appreciated many thanks 😊

Have included pics of gutted shower (with some plaster glue still to be cleaned).

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MitchellMc

Welcome to the Bunnings Workshop community @newtorenovating. It's fabulous to have you join us, and many thanks for your question about renovating a bathroom.

If you have a choice between Gyprock AquaCheck, and Hardie's Villaboard, a cement-based Villaboard sheet is generally the preferred option for most bathroom applications, especially in wet areas like showers. Once you choose Villaboard, it’s best to use the manufacturer’s recommended products for primers, membranes, and any adjoining sheets to ensure compatibility and maintain a consistent system. This also makes it easier to get advice or support from suppliers like Hardie if needed. For the waterproofing membrane itself, the Bastion 15-kilo under-tile waterproofing membrane would be suitable for your bathroom.

Before starting any waterproofing, check with your home insurer and local regulations, as in many areas bathrooms must be waterproofed by a professional to meet building standards, and the work may need to be certified. While installing the sheeting can usually be done yourself, it’s a good idea to speak with the waterproofer about their preferred products and methods, particularly in areas like shower pans or floor-to-wall junctions, to avoid any compliance issues later. Using a shower pan at the base is a practical choice and simplifies waterproofing in the wet zone.

By sticking with Villaboard and compatible products throughout, and coordinating with a professional waterproofer where required, you can ensure your bathroom renovation is both durable and compliant.

Here are some helpful guides: How to install Villaboard in bathrooms, How to install a shower base and How to waterproof your bathroom.

Please let me know if you have any questions.

Mitchell

newtorenovating

Thanks so much for your reply!

I appreciate all the advice 😊

Follow up question-

It's brick walls/solid cement floor-- if checked out the villaboard article, would I still secure to brick walls in the same way, and does there need to be a primer/layer on the brickwork underneath the villaboard due to it being brick/mortar?

Another question also please- the drain in the shower is off centre, however as the pan will be raised (need to re level the floor etc, create shower lip area again, place villaboard flooring sheets etc) I was looking at flexible drain solutions, such as this one-

Would this be suitable or is it better to get custom tray?

Many thanks again for reading, and your advice! I am getting a professional also but would like to at least install the villaboard myself, then once waterproofing is done, will tile myself also!

MitchellMc

Here's the wet area installation guide for Villaboard @newtorenovating. Timber or steel battens are fixed to the brick, which allows you to pack them out to achieve a uniform surface for the boards. The minimum depth of the battens is 35mm, so face fixing 70 x 35mm timber would be the preferred option.

James Hardie does not recommend fixing directly to a masonry surface.

Provided the flexible outlet complies with regulations, I would presume it is suitable. This is considered plumbing work, so it will really be up to the plumber as to the type of fitting they are willing to use. They might create the offset with a solid pipe rather than a flexible length.

Mitchell

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