More plumbing questions...

[Penners]

I'm looking at the dimensions of a WC on a supplier's website. It's available with an S-trap or a P-trap - I understand what those are. However, it quotes the following dimensions:-

S-trap 300mm roughing-in; P-trap 180mm roughing-in.

Please can someone explain what "roughing-in" is?

While I've got your attention, can anyone please tell me what the minimum and maximum figures are for the fall on a horizontal run of soil pipe between a WC and the soil stack? The loo is about 2 metres from the stack.

Many thanks.

 

[Gervase]

Roughing in is a term used to describe work that will be hidden. it's usually done as a first-fix, and the kit used is utilitarion and purely functional - so a roughing in P trap will be bog standard plastic and not very pretty, not chromium-plated or of a fancy design.
As for the falls, excuse me while I consult the regs...

 

[Gervase]

Part H.1 of building regs gives the gradient limits for a WC discharge pipe as between nine and 90 mm fall per metre. The maximum length of the pipe is 15metres, and the minimum bore is 100mm.
Hope that helps...

 

[Penners]

A great help, as always, Gervase. Many thanks.

I understand your definition of the term "roughing in" but do you have any idea what the quoted dimensions could mean (300mm and 180mm)? From what to what?

 

[Gervase]

You've got me there - it could just be the length of the 'tail' that connects to the pipe. Or the height of the outlet in relation to floor level. Our thunderboxes came with built-in traps, so it's not something I've had to explore. I'm not back on site until next week, so I can't grab a passing plumber, I'm afraid.

 

[Penners]

No matter - thanks for trying. I'll be putting the pipework in before the appliances anyway, so I can just position the wc to suit.

Many thanks again.

 

[tony]

Imagine not able to plumb in a toilet.

hasnt google taught uou anything

get a plumber!!

 

[tony]

yes there is a spelling mistake, as you always like to point out.

 

[Nemesis]

There's an edit button so you can correct spellings.

There's a first time for everything - go for it Penners. You couldn't make a worse job of it all than the 'professional' who was hired in a previous house to plumb in a bathroom.

He declared that the bidet couldn't be plumbed in so just left it without any waste trap and pipe (he said it was a non-standard size) and that we couldn't have bath taps in the middle of the bath as opposed to one end - and left that without any taps at all.


We managed to fit a bidet outlet and taps exactly where we wanted them.

Never hired a plumber since - it's not rocket science as we discovered.

 

[Penners]

go for it Penners.

Oh, I shall certainly be going for it. I ain't payin' no plumber's rates!

I've done plenty of plumbing before, but it's about 25 years since I tackled a waste system, and the memory isn't what it was.

Where was I...? Oh, yes - and this particular job is something of a quart into a pint pot (although I could perhaps have chosen a less distasteful analogy!)

 

[Jocelyn]

[Penners wrote:
I've done plenty of plumbing before,

but it's about 25 years since I tackled a waste system, and the memory isn't what it was.

Just so long as you remember where the p-trap is you'll be OK!

Joss

PS first time I've tackled one of these 'quote 'thingys

 

[Penners]

Just so long as you remember where the p-trap is you'll be OK!

I can normally remember until the 5th or 6th glass, then the consequences tend to get a bit random.