Create New Inspection Chamber to Access Another Junction for Rodding

[Blueberry100]

I have a kitchen extension built over an inspection chamber. Looking into this chamber, there is a junction where two pipes (from kitchen and upstairs bathroom) drain into a bigger pipe that then carries on outside of the extension (no neighbouring houses are using the bigger pipe - just me). If I create a new inspection chamber just outside of the extension (i.e accessing the bigger pipe) in order to create a new rodding point for the junction upstream, is this sufficient to cover any blocked drain issues? In other words, is it possible to rod a junction point (i.e. with branch pipes) from a point further down? How would you control which pipe you rod (kitchen or bathroom) if you were accessing the junction remotely? Just trying to see whether this is a viable solution as I want to tile over the extension floor without leaving the old inspection chamber visible (it is currently raised and sealed to scree level). Thank you.

 

[Newboy]

Not really a viable solution and very dependant on the distance between two chambers.

In the event of a serious blockage you'd end up having to break out the tiling to gain access to the existing chamber.

 

[Blueberry100]

The new inspection chamber would be around 8 feet away from the old one. Thanks.

 

[Hugh Jaleak]

Use an internal grade cover on the existing chamber. If tiled with care the joint isn't too noticeable. No method I'm aware of to steer a device into a lateral to unblock it, regs do state all drain runs should be accessible for rodding.

Sods law says the jetting hose will fly off up the lateral when you don't want it to though.....

 

[bernardgreen]

One solution to the problem is to add rodding access points as shown in green.

 

[Blueberry100]

Thanks for the response Bernard. I'm hopeful for what you've described, but your layout isn't quite what we have.
The situation we're in is like this:

The blue sections are current inspection plate locations. The "inside" area is the new extension.
The two branches outside lead to the downstairs cloakroom and the upstairs en-suite, but both will remain accessible, so I didn't bother labelling them.
The pipes inside and the pipes outside never intersect (as far as we can tell).

The kitchen sink one would be fine, we think, as it could be rodded from the kitchen or from a new inspection point on the main drain, outside. It's the one that leads to the upstairs toilet that we have concerns about. And then only if the blockage occurred in the upstairs toilet branch, at the bottom of the soil pipe.

We also checked and the bath, sink, and toilet in the upstairs bathroom all drain into the same soil pipe, which runs through the loft and out to the roof. When it enters the loft space it's connected to a flexible hose that looks like it's from a tumble dryer! If that was disconnected, could it be rodded from the loft down?

Thanks again for your help and assistance.

 

[Newboy]

We also checked and the bath, sink, and toilet in the upstairs bathroom all drain into the same soil pipe, which runs through the loft and out to the roof. When it enters the loft space it's connected to a flexible hose that looks like it's from a tumble dryer! If that was disconnected, could it be rodded from the loft down?

To be honest, the upstairs bathroom drainage sounds like a bodge job - you would never use any form of flexible connector in the location described.

If that was disconnected, could it be rodded from the loft down?

If the blockage was below the flexible connector in question and it was separated then you could end up with the contents spilling into the roofspace.

The advice given by Hugh is the most logical solution.

If this is a new extension then consideration should have been given to extending the drainage outside the building footprint and installing a new chamber.

 

[Blueberry100]

Agreed, flexible hosing doesn't sound like the right thing there. Personally, I think that if the blockage backs up that far then the zip ties won't hold it and we'll have waste in the loft anyway.

It's brand new, screed was laid today. We were told it'd be a small, round inspection cover that would fit under a single tile, but they put a large rectangular plate in place instead. Is conversion a possibility? Can we make the entrance to the chamber a mini inspection cover, the 250mm round ones or the 300mm square ones?

 

[Newboy]

zip ties

Oh dear God!

It's brand new, screed was laid today. We were told it'd be a small, round inspection cover that would fit under a single tile, but they put a large rectangular plate in place instead. Is conversion a possibility? Can we make the entrance to the chamber a mini inspection cover, the 250mm round ones or the 300mm square ones?

Bear in mind that the cover is to allow access to the chamber - it may not be pretty but it may be necessary.

How deep is the base of the chamber (what's the invert depth?)

To fit a smaller cover would need a significant amount of work to bridge the existing opening - your build sounds to have progressed too far to consider that option now.


Whilst having the cover visible (with the right choice of cover it doesn't need to be obvious) may seem inconvenient, it's a lot more inconvenient to have no access having to destroy the floor at some point in the future due to an inaccessible blockage.

 

[Blueberry100]

Bear in mind that the cover is to allow access to the chamber - it may not be pretty but it may be necessary.

How deep is the base of the chamber (what's the invert depth?)

To fit a smaller cover would need a significant amount of work to bridge the existing opening - your build sounds to have progressed too far to consider that option now.

Whilst having the cover visible (with the right choice of cover it doesn't need to be obvious) may seem inconvenient, it's a lot more inconvenient to have no access having to destroy the floor at some point in the future due to an inaccessible blockage.

From the top of the opening to the base of the pipes is somewhere between two and three feet. They built raised brickwork up around it to bring it up from ground level to internal floor level. I can't measure it as the floor is still wet.

I appreciate it might be a significant amount of work to reduce the size, but I'm tempted to enter discussions with the installers about having them do it. I feel that we were misled and the implications of the decision we took weren't explained to us. As I think someone said, it would have been much easier to do this from the start.

I know what you're saying about having it accessible, and you're absolutely right of course. It's just frustrating that we have to make that compromise given all the work we've done. If rodding or jetting it from the outside or from the loft is an option (even if it's not the preferred option) I might be happy to take that gamble, knowing that it'll cost more or end up with sewage in loft!

I think I need to get someone out to have a look at the whole set-up and see what they suggest. I'd like someone independent of the installers if possible. Any recommendations or suggestions?

Thank you all for your help, this is really useful.

 

[Newboy]

I would discount any chance of clearing a blockage from the external chamber.

The only practical way forward is to express your concerns asap with the contractors and see if you can find a solution.

I might be happy to take that gamble, knowing that it'll cost more or end up with sewage in loft!

That may seem like a reasonable gamble but, trust me, if you do have problems in the future you'll look back and regret it.

Inspection chambers are needed - if they weren't needed then they wouldn't be specified & installed.


I'd also be inclined to get the pipework in the roofspace sorted out - I can't think of any flexible pipework (rated for foul drainage) that would be fitted using cable ties! If the flexi is taking bath, basin and WC then do you really want a whole bath's worth of water pouring through the building.

 

[Blueberry100]

Understood. I'll speak with the project manager as soon as I can. Helpfully, the project manager has changed since the start of the project. The guy that said moving it would be "too expensive" and that it'd be a small inspection plate isn't the project manager anymore.

We'll speak with the tiler as well and see if he can reassure us about it's visibility. Maybe just getting the grouting to match the tile colour as close as possible would mean you really can't see it. The tiles will likely be dark grey so maybe it'll be ok.

As for the pipework in the roofspace, I'd never really considered it backing up to up there. I guess eventually it'd come out of the roof? It's got to go somewhere, I suppose! Currently I think the flexible pipe is in place because the roof vent isn't directly above the soil stack. Two 45 degree elbows will sort that out though, I suspect. I'll speak with my plumber about getting that replaced.

Thanks again.

 

[Newboy]

Sounds like two (or should that be three?) good plans

Best of luck.

 

[Ian H]

If you get a lid that can take tiles make sure they don't get any grout between the lid and frame because it will be a pain to get up.

 

[Hugh Jaleak]

Forget any idea of rodding from the loft down, you'd make a hell of a mess, that's if the rods will even get round the bend at the base of the stack. Only seen it done once, a regular job where it actually blocked in the stack, just below the junction for the WC. My boss went up the ladder with 2 rods and a plunger, quick shove and the blockage cleared. Pressure fluctuation also blew the contents of the (full) pan all over the bathroom....

Flexible pipework on the vent section is quite common, the flexible section couples with an appropriate tile vent, to avoid need for weathering slates to be needed. http://www.aboutroofing.com/manthor...55mm-to-fit-roof-tile-vent-tile-adaptors.html

The waste is never going to reach that height if the stack blocks, if there's a shower fitted, the level cannot get any higher than that, (or the WC if no shower present).

Look at the internal covers, full size and designed to be infilled with the appropriate floor covering to blend in. I'm not aware of any smaller covers that can be filled. An example here, http://joe-cornell.co.uk/s/cc_images/cache_2412651684.jpg?t=1329824065