Hi, I'm after someone's experience to guide me....
We have a particularly visible inspection cover in the middle of grass, which covers the chamber for a right angle in a buried 4"/110 waste run. I'm relaying an area of paving, and plan to cut the corner off the run with two new inspection chambers which, while adding a further cover, will be much less visible because of their location.
The job should be reasonably straightforward, using all plastic for the new chambers and pipe, except for one thing. The existing pipe runs have about a
10:1 fall, as our neighbours house is lower than ours. I know this is out of spec for foul drains, but it has worked without problem for the last 40ish years, so I don't propose to change the fall. It only takes the waste from the kitchen sink anyway...
Where I join the new chamber bases into the existing pipework I will therefore have to make a slight change of angle, or the risers on the chambers will be off from vertical. 10:1 is approx 6 degrees, and I assume the chamber bases will have been designed for 40:1, which is about 1.5 degrees - so I have to adjust by some 4.5 degrees.
I will be using rubber joint sleeves to connect new pipe to old, as the existing pipes are clay and about 125mm external diameter - link below. My question is: will the sleeves have enough adjustment to allow for up to the
5 degree offset required, or will I additionally need adjustable plastic bends. These are fairly expensive, and their length will need extra digging, so I'm hoping that someone has had a similar experience and has got away with just the rubber sleeves.
Thanks,
Charles F