Good morning all,I'm a newbie on here so be gentle! I am replacing an old ptrap drain with a bottle gully, I would like to bypass an inspection chamber that is 1.5 metres away from drain it has just the ptrap going in and out at a 90degree right turn. Can I put an adjustable 90 degree pipe on the new one or must I have an inspection chamber there. Oh yeah from the first chamber to the foul chamber is around 2.5 metres. Thanks for any guidance and information. Oh and the new bottle gully can be rodded.
How to install a replacement drain gulley (Ed.)
- Thread starter gdgman
- Start date
Is there a reason for this or is just best practice?
If the 90 degree turn in not acute or it has a long slow turn should I still put an inspection chamber in.
If the 90 degree turn in not acute or it has a long slow turn should I still put an inspection chamber in.
Slow bends are acceptable.
So do you think an adjustable 90 degree floplst turn is acceptable?
Don't see how an adjustable 90 degree bend is slow, when you describe it as a replacement for an existing bend of that angle. Perhaps a sketch of new and old would clarify the angles
A buried 90 degree tee would be a botch.
A buried 45 degree branch with a 45 degree single socket inlet would be less of a botch, but still a botch.
I've never seen a longer swept tee, I doubt they exist.
Tees are intended for use vertically, e.g. for a toilet to plug horizontally into a vertical soil stack.
Use a bottle gully so it's roddable.
But you should have a chamber.
A buried 45 degree branch with a 45 degree single socket inlet would be less of a botch, but still a botch.
I've never seen a longer swept tee, I doubt they exist.
Tees are intended for use vertically, e.g. for a toilet to plug horizontally into a vertical soil stack.
Use a bottle gully so it's roddable.
But you should have a chamber.
I am going to use a bottle gully but I don't understand the tee part of your advise. The current drain and pipe will be removed and filled. The proposed pipe is my issue, I still don't quite understand why it must have a chamber when it is only grey water, no solids. But if I must I must.
I see now, it won't be a junction as everything to its left won't be there.
Any underground 90 degree corner needs a chamber, as they're prone to blocking. 90 degree bends are for horizontal-vertical turns, not for underground corners. That's why they're 87.5 (or 92.5) degrees, so the "horizontal" pipe has a 2.5 degree slope.
Depending on depth, you should be fine with a mini chamber. Put it in at 45 degrees, with a single socket 45 degree corner plugged into its inlet and outlet ends. Do not use the side branches at all, leave them all capped off.
This splits the 90 into two 45s, making it much less prone to blocking. It also gives you access to each from the chamber itself.
You may think it's easier and cheaper to use one of the 90 degree side inlets. But then you'll end up with the chamber full of dead water and sludge sitting in that centre channel. It will stink and will be prone to blocking.
Any underground 90 degree corner needs a chamber, as they're prone to blocking. 90 degree bends are for horizontal-vertical turns, not for underground corners. That's why they're 87.5 (or 92.5) degrees, so the "horizontal" pipe has a 2.5 degree slope.
Depending on depth, you should be fine with a mini chamber. Put it in at 45 degrees, with a single socket 45 degree corner plugged into its inlet and outlet ends. Do not use the side branches at all, leave them all capped off.
This splits the 90 into two 45s, making it much less prone to blocking. It also gives you access to each from the chamber itself.
You may think it's easier and cheaper to use one of the 90 degree side inlets. But then you'll end up with the chamber full of dead water and sludge sitting in that centre channel. It will stink and will be prone to blocking.
https://www.screwfix.com/p/floplast-push-fit-3-inlet-adjustable-mini-access-chamber-base-300mm/18837
Just examples. All available for less elsewhere. Add risers as required and a lid. There is a maximum depth allowed for a mini chamber, I forget what it is but I'm sure someone else will know the number or google will.
Have to ask, why are are you replacing the entire run?
Depending on depth, if the drain invert is less than 0.6m deep, you may get away with a mini chamber on that bend as Ivor has described above. Any deeper and you'll need a 450mm diameter chamber.
Building Regs require a chamber at every change in direction of the drain, mainly due to the old school method of using rods to clear blockages. Appreciate it's only a Gully going on the end, but these still can and do block, and it also futureproofs the run, should anyone wish to put a WC onto it at a later date.
Depending on depth, if the drain invert is less than 0.6m deep, you may get away with a mini chamber on that bend as Ivor has described above. Any deeper and you'll need a 450mm diameter chamber.
Building Regs require a chamber at every change in direction of the drain, mainly due to the old school method of using rods to clear blockages. Appreciate it's only a Gully going on the end, but these still can and do block, and it also futureproofs the run, should anyone wish to put a WC onto it at a later date.
If you do have sufficient chambers then you'll probably never even need rods. Just lift the lids and squirt the hosepipe in until it clears in each chamber down the run.
At least with a bottle gully you can rod from the gulley if you remove the sleeve.
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