Drainage pipe under a driveway

Ramsey · Post: # 43697Post **Ramsey** Sun Dec 06, 2009 4:11 pm

Hi,

I need to run a drainage pipe under my tarmac driveway. It only needs 110mm solid pvc pipe, but will this withstand cars driving over it? It will be down 1 metre. I have the occasional heavy lorry in the drive etc. Would it be better to use twinwall drainage pipe, or even to put the pvc pipe inside a twinwall pipe just while it passes under the driveway?

Thanks

R

Post: # 43700Post **msh paving** Sun Dec 06, 2009 6:20 pm

1m deep is fine for 110mm pipe but to be on the safe side give it a 150mm covering with semi dry concrete ,allowing for expansion joints using a piece of compressable fibre board at any pipe joints, MSH

Sun Dec 06, 2009 9:05 pm

we always use 100mm of shingle around any pipe outside of buildings,leanmix when under buildings
LLL

Post: # 43708Post **Dave_L** Sun Dec 06, 2009 9:17 pm

and make sure any reinstatement backfill material for this pipeline is properly compacted using the correct machinery and not just a whacker plate.

As LLL says - leanmix around any sections of the pipe with less than 700mm of cover - pipe bedding will suffice for the rest of the run.

Post: # 43709Post **seanandruby** Sun Dec 06, 2009 9:25 pm

You'll be fine with pea shingle. make sure you backfill with good quality fill material compacted every 150ml. Cap it off then bring it up with DTP1.

Post: # 43719Post **Tony McC** Mon Dec 07, 2009 9:03 am

With plasticware, you *must* encase the pipe in concrete or it *will* deform and possibly collapse.

Much better to use clayware in such a situation.

flowjoe · Post: # 43724Post **flowjoe** Mon Dec 07, 2009 6:21 pm

Not sure about covering or surrounding in concrete ? its a load of extra work fitting joints to the system. At a metre deep plenty of granular pipe bedding will be enough with some carefull backfilling and compaction.

Post: # 43725Post **Dave_L** Mon Dec 07, 2009 6:28 pm

If there is insufficient cover then concrete is required, in my experience.

Edited By Dave_L on 1260210530

flowjoe · Post: # 43727Post **flowjoe** Mon Dec 07, 2009 7:15 pm

I think it is for 600mm or less Dave under hard landscaping or drives, personally i would always use a clay pipe just because you get a better finish on the inside of the joints.

Having said that clay pipes are easier to damage when a half brick tumbles in the trench and they fracture easily if not supported by the granular fill, both pipe materials work if done correctly