How to waterproof flooring for kitchen reno?

[AnneDyson]

Hi!

We're owner-builders doing as much DIY of our reno as possible. Our home has been restumped and 19mm yellow-tongue placed through most. Above this will be 19mm hardwood flooring, except for the kitchen where the travertine is 12mm thick. To both make-up the height difference and add waterproofing/resistance we're wondering if:

1. We can adhere thin (e.g. 4-6mm thick) cement sheeting to the yellow-tongue in the kitchen area (if yes, which product is best to use to adhere the two)

2. If we need to also waterproof the kitchen area (which product again is recommended)

Thanks heaps!

[MitchellMc]

Welcome to the Bunnings Workshop community @AnneDyson. It's wonderful to have you join us, and many thanks for your question about kitchen waterproofing.

Kitchens are typically not waterproofed. However, I have some concerns with installing hardwood flooring over structural chipboard flooring. Generally, hardwood flooring is attached to timber joists. If it's installed over yellow tongue, you'll need to nail and connect the flooring to it, and most suppliers would not recommend that as an adequate installation technique.

Hardwood flooring also creates the issue that when floors are mopped, water can seep between the boards and be trapped by the structural flooring beneath, which could cause its own issues. Waterproofing the structural flooring could just make matters worse, as water will now be trapped at the base of the boards. There might be flooring coatings that could seal the boards entirely and prevent water egress.

It sounds like it would be best if you consider using water-proof hybrid flooring for your build. This can be installed on structural flooring and will provide the water resistance you need.

In answer to your questions, you could consider using James Hardie 1800 x 1200 x 6mm 2.16m² Ceramic Tile Underlay Flooring and it would need to be glued and fixed down as per their installation guide. Stud adhesive is what's used as the glue for particle board floors.

Please let me know if you have any questions.

Mitchell