The Brew Cabin

Posted: **Mon Oct 26, 2015 2:37 pm**

Hi Everyone

I am new here but hope someone can offer some guidance! House was built around 1896.

A new basement lightwell is being created with a grill at ground level over the top. I wish to re-route the existing clay soil pipe around the lightwell walls in plastic as it currently runs right through the middle just below ground level. See the attached diagram - the proposed drain route is in red - existing route in green.

Reading other posts it seems that building regulations say that above ground drainage has a maximum length of 6m. The pipe is below ground level but only about 200mm and would be attached to the lightwell wall .......this might be pushing the limits of the regs! The problem is that the width of the light well is circa 1.5m and the length 5.5m making the length 7m before it would disappears below ground on its way to an existing manhole.

Is there anything that can be used to break the 7m that would make it comply with regs. Would a stub-stack with air admittance valve do the trick.

Any advice appreciated before meeting with building control?

Cheers
Martin

Posted: **Mon Oct 26, 2015 2:42 pm**

Sorry the picture is so large - trying to work out how to make it smaller!

Think that is better. Cheers

Posted: **Mon Oct 26, 2015 4:49 pm**

=> "Reading other posts it seems that building regulations say that above ground drainage has a maximum length of 6m"

Where is this in the building regs?

Posted: **Mon Oct 26, 2015 5:21 pm**

Thanks Ringi for replying.

Tried more 'Googling' and can only find references that say a WC cannot be connected more than 6m from stack.
Do you think this means that I am in the clear with the 7m length above ground soil pipe from the stack................ before it goes underground to meet existing manhole?
Cheers

Posted: **Mon Oct 26, 2015 5:30 pm**

I am not an expert!

The only limits I know are about ventilation of drains/stacks etc. For example I think the 6m limit for a WC can be overcome by using an air admittance value near the WC.

Posted: **Mon Oct 26, 2015 5:49 pm**

Thanks Ringi - let's see if someone else comes along with their thoughts

Posted: **Tue Oct 27, 2015 6:07 pm**

Martin you should really talk to your BCO or architect about this
building regs can be interpreted many ways
my main concern with rerouting pipe work is maintaining falls
LLL

Posted: **Wed Oct 28, 2015 5:28 am**

AS LLL. Building regs' can be a minefield of contradictions. It 15 metres force 6 toilets but only 6 metres for one ??? I think the main concern could be one of syphoning. I have done longer runs but not domesticated dwellings, because a length of plassy drain is 6 metres long without joints maybe it would be allowed with say hdpe pipe with welded joints. Not sure because i deal in below ground drainage. My main concern woul be the 90% bend, will need to be rodable.

The Brew Cabin

Basement lightwell soil pipe