New ensuite questions please

[PoodlesRule]

Hi, We are putting in a small ensuite, and have a few questions for the bits we are doing ourselves, we have a plumber, wet sealer and plasterer.   We have purchased a formed shower tray (so it does not need tiles) and will be enclosed on 3 sides with shower screen to front.

1.  When building the enclosing stud wall, how much extra room than the width of tray do we leave for thickness of wet seal so there isn't too much room, but enough to slot the tray in after they wet seal it?

2.  Because it will be enclosed on 3 sides, and the need to wet seal before installing base, we will need to put extra wall paneling on the 3 sides before putting in the laminated wall panels we have bought from Bunnings to create the notch in effect.  The walls are Hardiflex wet area Villaboard.  Do we just install extra 3 pieces of Villaboard above the base to duplicate a notch in? Does it need to be sealed also? And what do we use to attach the laminated panels to the wall lining?  (prefer something low odour as I react to a lot of glue smells).  We have the edge and corner joining strips.

Thanks.

[MitchellMc]

Welcome to the Bunnings Workshop community @PoodlesRule. It's wonderful to have you join us, and many thanks for your question about installing a shower tray.

Because you’re using a pre-formed shower tray, the manufacturer’s installation instructions are really the key thing here, as different trays are designed to be installed in slightly different ways. In most cases, you don’t allow extra clearance for waterproofing thickness at the sides. The tray is normally installed first, either hard up to the framing or notched into the bottom of the studs, and the wall linings then come down over or just into the tray flange. The waterproofing membrane is applied to the wall linings after they’re installed, not behind the tray, so you’re not trying to “slot” the tray in after waterproofing.

For three-sided enclosed trays, you usually don’t build up extra Villaboard to create a notch. Instead, the Villaboard is fixed to the studs so it overlaps or sits just inside the tray’s upstand or flange, and that lining is then fully waterproofed as part of the wet area system. Any Villaboard that forms part of the shower enclosure does need to be waterproofed, even if it’s above the tray. The laminated wall panels are then fixed over the waterproofed surface, and the waterproofing remains the primary barrier.

For fixing the laminated panels, most systems recommend either a neutral-cure silicone or a low-VOC construction adhesive, depending on the panel brand. Many people with sensitivity to smells have better luck with neutral-cure silicone, as it generally has much lower odour than solvent-based adhesives. Again, it’s worth checking the panel manufacturer’s instructions, as they’ll specify what adhesive is compatible and won’t affect warranties.

If you can share the exact brand and model of the shower tray you’ve bought from Bunnings, the installation method can be confirmed more precisely, so you don’t build something that fights the tray’s design.

Here's a guide on How to install a shower base, which shows the notching of the studwork, rather than stepped sheeting.

Please let me know if you have any questions.

Mitchell