On Apr 10, 11:07*am, "Ret." wrote:
harry wrote:
On Apr 10, 12:34 am, Cordless Crazy 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?

--
Cordless Crazy

You shouldn't need any sealant. Silicone sealants adversely react with
some plastic shower trays.
There are special traps availabe for shower trays. *Shower drains
don't block up much. If they do, one of the pump type things usually
clears it easily.
No drain should be horizontal, you are asking for trouble.

I suppose it all depends upon what you mean by 'horizontal'! A perfectly
horizontal pipe will not drain that well - but the drain from my shower
(which is in the opposite corner of my bathroom to the soil stack) has only
the slightest 'fall' on it - but it drains without problem.

--
Kev

+1 with Kev. But I would be wary about saying that shower traps don't
block - it does obviously depend on which type; I have one that is
accessed from the drainage grill and it does tend to collect long
hairs building up and being the hosts for slime films.
Rob