Laying Concrete Foundations

Once you've dug the trenches they will need to be inspected by the BCO, for width and depth.

When you lay the concrete the most important thing is it's level, also, it is an exact number of bricks below DPC.

 

Is it a small extension, level and solid ground, no services (gas, water) nearby ?

 

Apart from the bridging it is just a matter of getting the base of the founds flat and square to the sides. Remove any loose material from the bottom of the founds.

Only dig the founds out if you are going to get the concrete in within a day or so. You can get into an awful state if the sides collapse and you have to re-dig.

If using readmix make sure you have enough to do it in one pour and a use for any excess

 

As Phil says, I understand your BCO needs to examine the trenches before you pour the concrete.

They can make you do exploratory digs alongside it to prove the depth of the poured founds if you don't...

 

#doublework

 

And a cross BCO who will treat you with suspicion from that moment on...

 

And some BCO's are sticklers for sides of trenches being straight & flat bottom trenches.
A upset BCO can make your life hell.

 

Out of interest what depth you are planning on ?

 

Thats going to be quite a bit of digging and spoil to shift a lot of work this time year

 

Definitely involve BC. Few years ago I did a small 3m x 3m single storey extension on a new house. Because it was on made up ground (as the developers tend to do to avoid carting away much of the dig), and was <10m from an oak tree (about 9m away!) had to go down 2.5m and have it tanked!! So much concrete went down the hole it would never move in a million years, but BC was happy.

 

Can you drive a machine?? Might be easier/safer to do it by hand often a machine can be too much on small footings especially when close to your exciting house

 

How exciting is the house?

 

Whist it takes practice, getting reasonable results with mini digger inst't that hard - much less than hand digging 1m in heavy clay