Foul drain question - Foul drain question

[emailuser]

Hi everyone, this is my first post so please be gentle , i have seen lots of good information on this site, hopefully someone can help me out as Severn Trent are driving me mad.
I am having a rear extension done on my property ( 1935 detached house ), currently next doors foul drain (green line on image) runs under my conservatory and then into my manhole where all my foul also goes(black line) , then it travels approx 15 metres to the road where it joins the main sewer line , i have now found that in my garden there is a combined sewer and drain water pipe 450mm at a depth of 5ft , with the extension work it males sense to apply to severn trent to make a connection to this pipe to save the pipework going under my side extension(purple box old garage), first of all do you think they will allow me to make a saddle connection to this ? ., from reading their site it feels like a potential yes .. secondly the distance from my current manhole to the 450 pipe is approx 3.5 - 4m , but the drop is significant the current manhole and pipework is only around 0.75m deep from ground level while the pipe we would like to connect to is probably about 1.75m - 2m deep , are there any regulations about the steepness of such a drop ??? .. this is all new to me so any help really appreciated
image can be found here
diagram of drain

[msh paving]

I would be surprised if they let you saddle onto a 450dia. pipe with such a sharp fall and short run,as you allready have a sewer connection what will you gain,all you can do is ask the question to them and get them out to take a look, there could well be a charge for a new connection,which may far out way the cost involved working around the pipes as they are MSH

[emailuser]

Thanks for the reply , it just seems to make sense to go into this pipe instead of running the foul for 2 houses under the new extension

[digerjones]

just did around pipes and suround in concrete. to be on the safe side, renew pipe under new build with plastic unless it all ready is. i have done this type of thing a few times dose'nt take any longer just have to take your time digging around pipes. wound'nt bother with severn trent it would be a can of worms.

[GB_Groundworks]

if building control are involved they'll want you to isolate the pipe either side of the footing with rubber couplers, and protect the pipe where it passes through the concrete.

also your footing will have to below the level of the drains and there is the angle of repose rule that a 45 degree line from the bottom corners of your footing has to miss the pipe, as thats the way force is dissipated throughout the ground.

i doubt they'll let you connect into the main sewer, and at 2m down you'll need trench shoring to stop cave ins, ask the question but i doubt it.



Edited By GB_Groundworks on 1301599439

[emailuser]

Alas building control and severn trent are involved , we are trying to do the right thing, we have agreement to build close to the 450 sewer pipe for our extension foundatinos will be 650mm from th edge of the pipe we have had to cctv the pipe which shows ok, i probably agree from experiences to date severn trent are not very helpful and it will probably make everyones life easier to replace the pipe that currently runs under the garage ( then new build extension ), we now have another issues the pipe that runs from next door to our manhole is leaking , digging the ground to check foundations we see water !!! looks like sink water , we had the pipe cctbved at the same time as the 450 pipe and it shows the joints misaligned , probably been like it for years , but we will have to fix , now waiting for severn trent to come and tke a look as both houses are pre 1937 so i think it falls under section 24 and thus severn trents responsibility ... ( hopefully !! ) , i guess lining it will fix it .. the pipe run is about 8 metres ....

[Mikey_C]

i personally wouldn't put a foul run under a extension, especially a joint, one I would go round the extension.