I'm aware this topic has been covered numerous times on this forum, and I've probably read a great number of the threads but still seem to be failing. I've described in detail below what I've done, I'm hoping someone will be able to identify where I've been going wrong.
New upstairs bathroom. 10" joists at 400mm centers, with additional noggins added around the edge of the shower tray area. 25mm marine play base, screwed down to the joists (and noggins around the edges). Generous coat of PVA. Motor mix of 5 building sand to 1 cement (brand new bag). Various degrees of wetness of mix attempted. Laid to approx 15mm thickness and leveled with a great degree of care. The shower tray its self is ABS capped expanded polymer, 1400x900mm, laid directly onto the motor and tapped down. Pad is made a little wider (around 100mm) than the tray and then cut back once it's set-up for a few hours.
I've attempted the same method 3 times now, each time to the same failed result. The edges of the tray end up with a gap of around 5mm between the motor, thus allowing noticeable flex in the tray. Certainly more flex than I'm willing to accept.
Does anyone have any ideas as to where I'm going wrong? Whilst I could attempt with a stone tray (I know from previous reading a lot of people don't rate the lightweight trays), or even employ someone with some more experience, I'm fairly determined to understand my failures, learn from them and succeed. I'm assuming it's not impossible to install this shower tray. Any advice would be appreciated.
New upstairs bathroom. 10" joists at 400mm centers, with additional noggins added around the edge of the shower tray area. 25mm marine play base, screwed down to the joists (and noggins around the edges). Generous coat of PVA. Motor mix of 5 building sand to 1 cement (brand new bag). Various degrees of wetness of mix attempted. Laid to approx 15mm thickness and leveled with a great degree of care. The shower tray its self is ABS capped expanded polymer, 1400x900mm, laid directly onto the motor and tapped down. Pad is made a little wider (around 100mm) than the tray and then cut back once it's set-up for a few hours.
I've attempted the same method 3 times now, each time to the same failed result. The edges of the tray end up with a gap of around 5mm between the motor, thus allowing noticeable flex in the tray. Certainly more flex than I'm willing to accept.
Does anyone have any ideas as to where I'm going wrong? Whilst I could attempt with a stone tray (I know from previous reading a lot of people don't rate the lightweight trays), or even employ someone with some more experience, I'm fairly determined to understand my failures, learn from them and succeed. I'm assuming it's not impossible to install this shower tray. Any advice would be appreciated.
