How long is too long..?

[PeterW]

Just been looking at drains layouts and I have a query.

 

How long is too long from a WC to a mains drain..? Given this is a part conversion and part extension, its going to have to be an external soil stack as I've got no reasonable internal route and as it is I can insulate the stack entry points to minimise losses.

 

Currently, the longest WC run is as follows :

 

WC to Stack - 5.2m 

Stack to IC 1 - 8m

IC1 to IC2 - 21.5m (22 degree slow bend at 6m)

IC2 to Main Sewer - 6m

 

I have plenty of ability to create a gradient, and the last IC2 will have a back drop as it will need to drop around 2.2m currently. 

 

Question is - is that too long and will it create problems..? IC1 is only to create an access point and a 45 degree turn - the rest is in 110mm uPVC and all showers, WCs and kitchen etc will use the same run, mostly joining either at the stack or with 1m of the stack bottom.

 

Thoughts..??

[Crofter]

So long as you have rodding access at frequent intervals, and maintain an appropriate gradient, I'm not aware of any limitations on distance.

[Daedalus]

Externally you've got no problems.

 

Distance between IC's is between 40 - 90m allowable. I would just make sure all the points are rod-able, especially at the base of the stack.

 

I though the length of branches was limited to 3m for a 40mm pipe although this might only be without an additional AAV (see attached). Although I've just installed an internal shower waste which is around 5 ish meters to the hopper and no problems yet.  

[Declan52]

From my external wall to where my system joins into the mains is approx 60m. I have 3 manholes along the route as well as access at the wall if needed to rod.  As long as you have enough fall I doubt you would have any problems.

Just make sure all the pipes are cut square and butted fully in place and most importantly you have filed any cuts so there are no ragged edges to catch toliet paper.