On 21/11/2017 12:14, Huge wrote:
On 2017-11-21, Martin Brown wrote:

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I have been impressed by how well the low profile trays behave when used
with a high flow rate drain there doesn't seem to be a problem. YMMV

+1.

We have a 1400x900 low profile Mira tray, fed by a twin head Mira digital
shower and it copes fine.

We already have a high flow rate waste, but I suspect that the the
problem we have is caused by:

- 3 long haired users who don't tend to remove hairs from the waste
during and/or after showering, and can easily find themselves in 5-8cm
of water (don't ask...)
- a long run for the 40mm waste pipe to the stack: around 3m with
several bends
- Tray raised by 90mm off the ground, with waste pip running
horizontally on top of floorboards behind cabinets to the stack.