Underground Drainage

[val101]

hi all

i am fitting a new sink to an extension on the house. all internal pipework has been done. the problem i am having is on the outside.

because we have a manhole/drain near to where the sink is to be fitted i was advised to take the waste pipe from inside the extension to the outside and fit a new drain outside for the waste water to collect then take a 4" pipe to the main manhole/drain.

the problem i am having is that after digging the trench to a depth of about 1m i am still about another metre away from the bottom of the main drain, thats where the additional connectors for the 4" pipe are. one plumber told me that it might be possible to just drill into the side of this main drain and connect the 4" pipe into the side of it

however he did say that because the water would then have to drop 1m to make its way out into the main sewer the water and waste might end up hitting the sides of the main drain and the splashes from the water hitting the bottom of the drain may cause problems with blockages.

without digging down another metre i was thinking is it possible to drill into the main drain and then on the inside connect a 90 degree elbow some more 4" pipe then another 90 degree elbow to help the waste water take the correct route to the sewer instead of having it splash about. any ideas would be welcome, many thanks

 

[justlead1]

Hi. It is possible to fit that which you described. However it come under building regs some of the officers have their own ideas on the practice used and do not like the tumbler to be inside the manhole. Although contra to regs you would not be the first to discharge from 100 mm pipe at high level into the manhole. Good luck

 

[ifielding]

The last post is spot on and I have seen it many times. I would advise you to contact your local building control and ask advice and even better get them out. It is free advice and you get the SP at your local level. I often phone them to double check on connections etc. Just be aware if you go down the wrong route and blockages/damage occurs to main system you are liable, which is mega bucks! It is the age old question... 'what to lose, what to gain' good luck mate.