Water proofing a deck to use the space underneath

[jopeters]

I am planning to building in the space under my house ( qlder style ) as a rumpus room which will involve water proofing a small deck area that is directly above part of the room. 

My plan was to pull up the exisiting timber decking and place down FC flooring sheets or similar, apply a water proof layering and tile over the top.

Id love any advice on what water proofing products are recommended for this kind of job 

[Jewelleryrescue]

Hi  @jopeters 

There are a multitude of Water proof products these days. This is a decent option and good bang for buck.

The trick for you might be to water proof up the walls a little 300mm to ensure the water flows towards the exit point you create maybe? a  sink drain  hole    or a floor waste like in a bathroom if a lot of water expected in there any trapped water needs to escape just be mind full.

A light rain will evaporate  etc, so no plug hole required

Re water proofing use mesh bandage at the wall floor joins so water doesn't flow down the wall gaps

Hope this  helps

[MitchellMc]

Welcome to the Bunnings Workshop community @jopeters. It's marvellous to have you join us, and many thanks for your question about waterproofing a deck.

I'd recommend using Secura flooring, which has the tongue and groove. You can then waterproof over the top. Here's the installation guide, which also includes waterproofing details.

Please let me know if you have any questions.

Mitchell