Browse Forums Bathrooms and Laundry 1 Jan 12, 2021 9:58 am Hi All! I'm after some expert advice on the current best practice on what to use/how to construct the right base for tiling a bathroom floor where the subfloor is based on compressed particle board. We live in a pole home, so all our floors are generally 19mm Yellow Tongue particle boards. I'm renovating our two bathrooms and ripped out the existing floor completely and plan to do it all from scratch for the new bathroom. The old floor was basically yellow tongue boards, then a layer of waterproofing membrane surrounded by a metal band along the edges where it joins the walls, then a mortar bed and then the tiles on top. Based on some research on various forums, I'm planning to use James Hardie's Scyon Secura Interior FC flooring 19mm sheets instead of the yellow tongue particle boards. Now my question is this: Is it ok to use ie James Hardie Ceramic tile underlay on top of the Scyon sheets and then tile on top of that (with all the waterproofing in between of course) - OR - is it better practice to do another mortar bed on top of the Scyon sheets and not use tile underlay? The shower base will obviously be screed, but outside the shower I was hoping I can use the tile underlay and not have to worry about a mortar bed since the tile underlay would be easier to install. Note that since this is a pole home - there may be slightly more movement in the house/floor than a regular house - so one important point for the new floor is also to avoid tile cracking as much as possible. So not sure if a mortar bed or the tile underlay is more flexible in that regards. Any tips on that matter would be much appreciated! Thanks in advance Re: What base for bathroom floor tiling over particle board? 2Jan 12, 2021 8:12 pm How thick is the mortar bed? Is there thinset (tile adhesive) on top of that? Forget mortar outside of the shower. JH has very detailed installation documents on most of their products. See what the secura one says. Tile underlay is cheap so I would use it on top (it’s glued and screwed). Hi, I'm clearing the tiles from our horrid 50 year old bathroom and preparing to lay new ones. Bugger of a job getting the old… 0 6075 I've filled, levelled and compacted around 100mm of roadbase in preparation to lay some outdoor court tiles. Prior to doing the final compaction, I dusted the top with… 0 2606 I have seen poly marble shower bases last in excess of 30 years 1 3044 |