3" soil stack

[aujm98]

being in the plumbing and heating industry for 45yrs+ has never amazed me how we come across different challenges/problems to solve 99% of the time iv'e always coped this is part of the 1% time or maybe iv'e got blinkers on and can't see the wood for the trees.This one project come's with the renewal of a WC and cistern to replace.Now the existing WC is of the siphonic type which go'es into a 3" soil stack not just the outlet but the whole of the stack is in 3" cast iron.This i know was common practice for siphonic close coupled WC's.The new toilet is not of the siphonic type but of the more common ordinary flush type close coupled suit,the question i ask is could there be a problem,to start with or in the future connecting a 4" outlet to a 3" outlet my heart of heart tells me that a re-newal of the existing soil should be done but this is were the blinkers come into this question, help with idea's to let me see the wood through the tree's, would be ever so grateful

 

[SimonG]

I think I'd be following your heart and a new 4" stack.

 

[aujm98]

heart of hearts it is :66:

 

[Whn1]

I've come across this a few times where the customer refuses to install a new stack, mcalpine make a multiquick that reduces to 3" haven't had any comebacks so far. Though I have changed my number a few times.

 

[aujm98]

thankyou Whn1 its good to see that this format of stack is not an isolated one yes of course the customer will always dictate unless it's a necessity I only posted the question in the hope for an answer as to what might happen if anything at all this stack indeed has been erected since the 30's seemingly no problems the syphonic toilet is not the original just giving me the impression that a newer more conventional suit would work with no problem yes I know that a 4" stack is the standard size with this existing stack, now that poses my question and was rather wondering indeed what is the reason if any to upgrade?

 

[stevetheplumber]

unusual to get 3inch cast stacks mostly we see 3and 1/2 inch stacks round here best plan is fit with reduced multi quick with a warning of possible problems then if it works eevery ones happy if it dont youve covered your bum

 

[Paulus]

I'm with steve on this one. There are lots of times when problems with what the customer wants could occur and provided they are warned up front I have never had a problem when additional work is eventually needed.

If it's a customer you don't particularly know I would put your reservations in writing and keep a copy as some people can have short memories when they choose.

 

[Roger Welton]

Agreed, written quote for both options stating potentiol issues with the 'quick fix' both parties are then know all the facts and there is no doubt about it.

 

[Guest123]

Never known of a 3" soil stack for a toilet. Cast iron is either 31/2" or 4". For rainwater pipes combined with the waste from kitchen sinks 3" is the norm, especially in Glasgow tenements. The price of 3" plastic and fittings is now extortionate compared to 4" plastic and fittings. A classic case of supply over demand.

The good news is that there is a Timesaver reducing coupling from 4" to 3" available for cast iron, plastic and copper pipe and 4" plastic will fit into a cast iron collar with a bit of "persuasion" but leaving no space to seal it and you must thoroughly clean out the collar of the old lead and rope. Otherwise a 31/2" Multikwik pan connector or pan extension will fit to your cast iron.

Post some pics and we will be able to help you better, and let us know how you get on.

 

[E4gas]

Never known of a 3" soil stack for a toilet. Cast iron is either 31/2" or 4". For rainwater pipes combined with the waste from kitchen sinks 3" is the norm, especially in Glasgow tenements. The price of 3" plastic and fittings is now extortionate compared to 4" plastic and fittings. A classic case of supply over demand.



The good news is that there is a Timesaver reducing coupling from 4" to 3" available for cast iron, plastic and copper pipe and 4" plastic will fit into a cast iron collar with a bit of "persuasion" but leaving no space to seal it and you must thoroughly clean out the collar of the old lead and rope. Otherwise a 31/2" Multikwik pan connector or pan extension will fit to your cast iron.

Post some pics and we will be able to help you better, and let us know how you get on.

My pal works in Miami,, ( he said ) they have 2 inch waste stacks for toilets

 

[Guest123]

My pal works in Miami,, ( he said ) they have 2 inch waste stacks for toilets

No way after I've been to the loo after a kebab could any 2 inch waste cope. It would be like a plumbing armageddon.