We have a concrete subfloor, on which we intend to use 75mm insulation where the shower tray will be installed, with liquid screed on top. We can go for 47mm thick screed, which with the 28mm thick tray would bring it to the same height as the 100mm insulation and 50mm screed in the rest of the bathroom. Looking at how the linear drain and waste fit, would we be best to shutter off this area and fill this later after the waste has been fitted? We intend that the waste pipe is channelled into the floor insulation to the external soil pipe. One other question is about using mosaic tiles. They obviously can't follow the exact line of the angles on the shower tray. Is it Ok to use mosaic tiles, using a little more adhesive where the angles meet to avoid any air pockets?
Thank you for your question.
You can either install the tray at it's future destination (if that's possible) and screed around or do the shuttering off and screeding. If mounting the tray at appropriate level before screeding is not possible, you should shutter the area off, fill with concrete and then insert the tray, with grooving some space if needed.
The tray is suitable for mosaic floor as long as it's not smaller than 10 mm x 10 mm. Having the small mosaic tiles not aligned perfectly with the slopes of the tray is not an issue, there will still be difference in height of the tray on the edges and near the drain, so water will still flow towards the drain.
I will be happy to answer if you have any questions.
David 0800 080 8859