BCO and access chamber

[sm_jamieson]

I have used a mini-access chamber 300mm diameter (floplast from screwfix). Max height 600mm (in line with building regs). All exposed at present / no infill. The drain was a little deeper than I thought and and height from invert to ground level is around 700mm. Max height with risers = 600mm, but I am going to use an inset lid over the whole thing anyway, to contain the patio paviours, i.e. there will be the plastic lid and another cover over. How likely is it that the BCO will fuss about the depth from ground being a little over 600mm ? Thanks, Simon.

[Bruce]

Why not ask them?

[sm_jamieson]

For some reason I never consider just phoning them outside of the inspections. But its still good to get some idea first so you can choose your approach ! Simon.

[Bruce]

I think most of them prefer to be asked, rather than find a problem at an inspection.

[Lobster]

I certainly agree with that; however it runs the risk of not getting the answer you want! Eg, if the OP asks the question directly, he might be told no, 700mm is too much, whereupon he has no option but to do the needful; on the other hand if he doesn't ask, the BCO might not notice or care about the extra height and he could get away with it.

(I haven't a clue how significant the actual issue is, BTW)

David

[Hugo Nebula]

On Fri, 18 Apr 2008 23:02:38 +0100, a particular chimpanzee, Bruce randomly hit the keyboard and produced:

However with something like this, if you phone up and ask the question, "is it acceptable to install a 300mm diameter chamber deeper than the maximum?", you're likely to get a negative answer.

OP: OTOH, if you were to install it, it might not be picked up on the inspection. OTOOH, it might. "Ya pays ya money...".

Think about why a wider chamber is called for at greater depths, and try this little experiment: lying on the ground, can you get your hand to the bottom of the channel? If you can't, how are you going to be able to clear a blockage if it did occur?

[Jim Alexander]

No idea but here is how I solved a similar problem.

bottom outlet means the inlets don't need to be so deep resulting in less digging for the inlet trenches.

Jim A

[sm_jamieson]

Well, I've sent him an email saying I've done it and realised after it was a little deeper. To be honest the final ground level is a little uncertain anyway. The house next door does not use a 450mm chamber at the same location for the drain. Also, do people really get down into a 450mm chamber to clear it ? More likely to poke with sticks I would have thought. And my arm is over 700mm long. Also of course the issue of bending the drain rod in a smaller diameter chamber is relevant. Simon.

[Andy Hall]

Send for Dynorod?

[sm_jamieson]

Well, the original BCO did not reply (still working there ?) so I sent it to the general building control email address, and some numpty there said "it appears you have used an unsuitable chamber" etc, so I will have to change it. I thought about lowering the ground level by

100mm, and it will be lowered slightly anyway in fact, but it would look like and would in fact be, an attempt to beat the system. Which you cannot ! Another 100 quid then ! Simon.