I get asked about this often as I’ve just added them to two recent bathroom renos.
There’s two products on the market that I recommend and are affordable. They are – Easycraft Wet Area Panels & James Hardie External Cladding. Both are available at Bunnings (I am not sponsored or never have I been gifted any of their products).
I don’t recommend one over the other because it depends on stock! Easycraft is a lighter and more manageable product to cut yourself. James Hardie is cement sheeting so a bit trickier to cut but it’s very heavy duty and meant for the water.
They just replace the need for tiles. You will still need to sheet behind with regular bathroom villaboard , then wet-seal as per building code, then attach the sheets over the top. I recommend ripping old cornice off adding a new one after as the sheets will be thick and you’ll need a better finish. Around the base you can either silicone (if you get a perfect finish on the bottom) or if your walls are out you can add skirting tile, or painted and sealed regular skirting.
These cannot go in your actual shower. Only on the surrounding/adjacent walls.
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