Using black soil pipe below ground

[Mr M]

I need to fit a couple of new plastic rainwater gullies. I only need about a 1ft length of pipe from each new gully, down to get me past the 1st socket on the existing salt glazed pipes which I am connecting onto. I already have some offcut lengths of black above ground 110mm dia. soil pipe over, from when I Installed this previously. Would I be OK to use a short length of this below ground to avoid having to buy a 3m length of the brown coloured pipe.

Would the black soil pipe be compatible with the offset bend push-fit fitting which I need to fit between the gully and the pipe (to get the change in direction)

 

[Richard C]

Building Regulations state underground soil pipe must be brown to distinguish it from other services. If you were doing work being inspected, the BCO would in all probability reject the use of black underground. You can get 1m lengths of soil pipe.

As far as I understand it, the black stuff is primarily for external soil stacks & has a strong pigment in it to help prevent Uv damaging the plastic & I also seem to remember something about preventing ingress of light & rats ; I’m not really sure why there is also grey & white other than aesthetic reasons! They are all made the same size & so each will fit the other.

 

[noseall]

There is no difference other than the 'coloured' plastic is unjustifiably more expensive because of its weather tolerant colour. Neither will degrade underground.

As for distinguishing from services, then no, there is not a precedent.

 

[Richard C]

As for distinguishing from services, then no, there is not a precedent.

So is that another myth blown then? Must admit I was relying on a “Chinese whisper” rather than something I’ve actually seen any reference to it in the Regs. It does seem a bit silly; but then a lot of the Regs are.

 

[Thermo]

they all look the same when you hit them with an excavator anyway!

 

[noseall]

they all look the same when you hit them with an excavator anyway!

Or a pick!

 

[Richard C]

they all look the same when you hit them with an excavator anyway!

A little story that hopefully will make you smile. I have a long time & very good friend who is an NHBC builder & developer & I see him at least weekly. He told me he’d been doing a job today, dealing with a surface water drainage problem on a drive which involved providing new drainage pipe work to a new soak away. He digs the trench, lay’s new pipe & starts digging a soakaway pit with the JCB; suddenly he feels something not quite right, gets out of JCB, looks down hole to see what appears to be a large cast iron main surface water drain with a JCB tooth sized hole in it; shines torch in, sees water flowing freely, adds a saddle, connects up his new pipe work & fills it all in & is going back to finish off/repair the drive tomorrow. I’m no lover of cowboys but he loves to wind me up & it’s more outrageous than a bodge; I just couldn’t help but laugh.

 

[Mr M]

Thanks for the responses. A couple of quick questions regarding the correct Installation of the gully and short length of pipe for connection onto the existing.

BTW, I am having the whole driveway excavated out to about 300mm deep and then stoned up with 8" of MOT 1 (40mm to dust) next week, but I am going to Install the gullies this weekend

1) I am going to bed the gully on some concrete, probably about 4" under the base of the gully. Is this adequate?

2) Do I need to shutter off and surround the sides of the gully in concrete as well or should I just leave the MOT1 to surround it?

3) Should I bed and surround the short length of pipe (probably only 1ft long) in concrete or just leave the MOT1 to surround it?

Cheers.

 

[Thermo]

they all look the same when you hit them with an excavator anyway!

Or a pick!

no thats your head!

 

[noseall]

1) I am going to bed the gully on some concrete, probably about 4" under the base of the gully. Is this adequate?

More than adequate.

2) Do I need to shutter off and surround the sides of the gully in concrete as well or should I just leave the MOT1 to surround it?

Loose fill material will be fine

3) Should I bed and surround the short length of pipe (probably only 1ft long) in concrete or just leave the MOT1 to surround it?

Pipes passing under driveways or surfaces busy with vehicular traffic should be encased in concrete.

 

[Mr M]

Job done today. Many thanks

Mr M