Foundation ground level

Hi all.

Been on here before, great site, and i am a bit of a lurker, tending to read
everyones replies.

However, i am just embarking on a 4.3 metre x 4.3 metre single storey extension to our bungalow ( greatly assisted in my drawings by Shytalkz....drawings all passed first time)

The question is....Over the length of the 4.3 metres for the proposed building, the ground height differs from front to back by some 80mm or so.

What level would the building control officer take as being ground level height, is it 150mm below dpc or actual ground height at the lowest point.

I am mid way digging my footings out and i do not wish to go to far down if not required, both for cost in concrete and also my self preservation.

Thanks for any help guys

Tufty

80mm what 3.1/2 inches You`ve not met " 3 metre Peter" from Wealden, then

Are we talking about an extra wheelbarrow of ground and £5 worth of concrete?

If the BCO is worried about 80mm over 4300mm, then he wants pushing in the trench prior to concreting

But to answer the question, it is the suitability of the ground which matters, so if its suitable at 920mm then that is the level to work to

Thanks guys, probably me being too fussy.

Whats the story with 3 metre peter then ?....sounds like i dont need him in my area !