Drainage pressure test / Waste Test - Am I in Trouble

[JustStartingOut]

We are a long way through our build and I have had a general builder do most of the work, can't complain about the quality but just looking at what Building Control Need, I see that pressure testing of drainage and from what I understand the whole waste system.

 

I know the builder hasn't done any testing and never mentioned any was needed, I think this is the first new build he has worked on.

 

We have all the plumbing in, how will we be able to get any tests done.

 

The connection on our property off to the main sewer is around 8 foot deep and the chamber is classed as a 'non-person access' chamber?

 

We have another small chamber as there are two pipes from the property going into a single pipe running to the main chamber and is where the pipes change direction.

 

Once in the property all pipes are now covered by plasterboard and the soil pipes vent out to tiile vents on the roof.

 

What tests will the inspector expect to see or have documented?

 

How can the internal pipes be tested as there is no way to block off the venting out through the roof

 

Am i going to have major problems or are there any simple solutions or am I misunderstanding the tests.

 

Edited January 26 by JustStartingOut

[ProDave]

It is definitely a requirement here.

 

Outside underground pipes were tested when BC inspected them before filling the trenches.

 

For the final test of the house pipes you plug it at the closest IC to the house, surely that won't be 8ft down?  and you cap off any vent pipes.  In the case ot a file vent you would uncouple the flexi connection and plug the top of the rigid pipe.  I assume you have access to that in the loft.

 

Then you should be able to pressurise it up to the depth of the lowest trap, in our case that was 80mm.

 

Your "fun" starts if it won't pressurise as you would have absolutely no idea where the leak(s) is.

 

If BC ask for this test pass their request to your builder / plumber who both should have known it would be required

 

 

[NewToAllOfThis]

Thanks for the reply, the builder did all the plumbing for the waste so as mentioned not sure he knew that testing was required.

 

No actual loft so will need to cut the plasterboard to get to the vent pipe join to the tile vent.

 

How do you stop the air escaping through the plug hole and overflow or will the water in the u-bends be sufficient for the air test

 

Sounds an expensive problem

 

[saveasteading]

29 minutes ago, ProDave said:

surely that won't be 8ft down

An access chamber needs to be accessible so if it's not, then that would be a bc failure in itself.

The testing kit costs £40 or so, though there are  better (as in ease and robustness) for about £60.

Your builder not having one is a worry.

 

@ProDaveis correct that there should be ways to do all runs. If any is really a problem, then at a push, the bco may accept that you plug the downstream ends, fill with water at the appliance end, and observe that it doesn't reduce.

 

There is no reason why there should be leaks without some bodging going on, so it should all pass.

 

BTW when we did ours, I tested each run before moving on. That's plain common sense. As it happens the bco trusted us and didn't want to observe another test. I guess ' why would we cheat ourselves).

 

[Mr Punter]

55 minutes ago, NewToAllOfThis said:

How do you stop the air escaping through the plug hole and overflow or will the water in the u-bends be sufficient for the air test

 

 

That's the one.  The traps are filled with water.  The test does not require much of a head so won't blow the water traps.  You can do internal by bunging up the soil pipe and external by bunging up a drain.  You sometimes need to do smaller sections.  Make sure you do it before the BCO is there so they don't witness a fail.

[Temp]

You can get a kit from screwfix/toolstation to do the test yourself before the BCO comes to witness it. 

 

It consists of a 110mm plug with a rubber hose and a bulb you squeese by hand to pressurise the pipe and a pressure gauge. You lift an inspection chamber and insert the plug, pump it up and check it maintains pressure on the gauge.

 

The pressure test is very low pressure, typically only a few inches of water as that's all you have in the traps to resist it.

 

Worth doing before the BCO comes so you can fix any issues. I forgot to put water in the washing machine trap. Lot of head scratching with the BCO present wasn't good for the nerves.