Surveyor has rejected foundations...

[jasel]

I am part way through my first project part of which involves a small 2mx3m side extension with architects plans that say the depth of the foundations required are 1.1m. I have been away and returned to find that the foundations were dug and the builders had drilled a hole ready for the inspector to come and look at... The inspector has subsequently come round and stated that a depth of 2m is required as there is a Willow tree 20m away that may be an issue in the future.

I would be grateful for advice on:
1) Is there any options to overcome having to dig 2m?
2) If the builders have to dig 2m vs. 1.1 what would the cost differential typically be. i.e. Had a builder been quoting for 1.1m and then had to quote for 2m for a 2m x 3m space, what would the difference for the digging and concreting only be...

Total newbie would be grateful for any advice you can offer...

Many thanks,
J

 

[DenzB]

I had a situation like this where building close to a tree. The only solution was mini-pile foundations (100mm dia piles driven into the ground). It's not cheap though, but you have compare that against the cost of digging 2m foundations with associated precautions such as trench shoring and the extra cart-away. Also (depending on location) you may have problems with the Party Wall Act. This regulates against digging too deep close to the neighbours property.

 

[freddiemercurystwin]

I hope you mean the builder has only dug the trench not poured any concrete? The inspector should always inspect before concreting.

1) Only by getting a structural engineer involved
2) You'll have to pay what it costs. Ask him to break down the extra costs for you.
3) This is what your contigency was for!

 

[jasel]

1) Only by getting a structural engineer involved
2) You'll have to pay what it costs. Ask him to break down the extra costs for you.
3) This is what your contigency was for!

Thank you. Have put aside contingency, but want to ensure that I only use whatever is required of it and not be coersed into parting with more than is fair and reasonable.

 

[noseall]

to dig the extra metre or so is a heck of a lot more difficult than digging the first metre. the trench may need shoring up, plus it is at the limits of say a micro excavator.

there may be water table issues too. plus, if there are any drainpipe runs close to the trench, shoring may be essential or a cave-in, complete with broken drainage, is likely to occur.

 

[Fluffster]

Cut the bloody tree down.
Pete

 

[Mr M]

Root barrier maybe?

http://www.hy-tex.co.uk/ht_geo_rb.html

Potentially, still a lot of digging out though

 

[jasel]

Thanks for the replies folks - the builders have just got on with it and I came to an arrangement with regards to the cash. Looked into some other options with regards to the tree and managing the spread of it's roots, but they are far more time consuming and expensive.

Thanks for taking the time to reply.