Inspection Chamber Install

[christianbeccy]

I'm just in the process of installing a long drainage run for my self-build. All is going well, but what's the best way to bed the chambers in?

I've installed 3 Osma 450mm chambers each with 2 risers, 1 will be positioned in a shrub border so won't be driven over, but 2 of them are in the middle of the driveway track. The drive will be geocell with gravel infill and top coat. So far, I've bedded all the drainage pipes and the chambers into 10mm pea shingle. I've backfilled most of the trenches now, just leaving the area around the chambers open.

So, at this moment, the chambers are sitting in pea shingle, I can see the tops of the ports still. What would you suggest next? More pea shingle, then a 150mm concrete top collar?

 

[Bonni]

I always bed the 4" inch pipes, manhole bases and manhole sides in pea gravel.

 

[^woody^]

Fill it in with soil, wait about a year for it to consolidate then form your concrete ring

 

[oldbutnotdead]

BCO up here is a big fan of concrete under the manhole base (and pea shingle around the tubes of course,)

 

[^woody^]

BCO up here is a big fan of concrete under the manhole base (and pea shingle around the tubes of course,)

That's what we do as standard. I was a bit surprised when I just checked the Osma guide and it says gravel!

 

[noseall]

We always pack concrete around/under, etc our chamber bottoms. Keep the knock-outs clear though, just in case.

 

[christianbeccy]

That's what we do as standard. I was a bit surprised when I just checked the Osma guide and it says gravel!

That's what got me. I called their Tech Help too, no use whatsoever! He basically regurgitated the text from the diagram