Cordless Crazy wrote:
A few questions:

1. When fitting a chrome shower waste grid with a back nut and two
rubber seals, would you use silicone to provide an additional seal to
the tray when clamped?

2. Am tiling the floor of my new bathroom, so any access to the trap
after the shower tray is installed, will be nigh on impossible. What
is the best trap to fit in a situation where I can really never get
back to it in a hurry? Anti-vac bottle trap or regular 75mm P trap?

3. Due to the arrangement and levels of the pipes, the shower waste
will being connecting in to a horizontal soil pipe on the side.
Should I be overly concerned with a possible blockage in the stack
and back-flow up the shower waste? Would hate to see parts of Mr
Hankey popping up in the shower tray. Is it wise to fit a McAlpine
non-return valve? How reliable are these with hair and gunk from a
shower?

When I did a complete bathroom makeover three years ago, I replaced the
airing cupboard with a shower cubicle and connected the drain from the
shower into the same pipe that the sink and bath drain into prior to
reaching the soil stack.

Of course I should have foreseen that when the bath was emptying the water
would back up and start to fill the shower tray! Fortunately for me I had
had no choice but to fit a raised shower tray and so I was able to remove
the trim below the tray and get in to fit a horizontal hepvo valve just
after the normal shallow shower trap. It has worked fine since fitted and
has not clogged up or required cleaning.

--
Kev