advice on existing extension foundations please...

[r6deano]

Hi guys,

Been a very long time since I have been on here. Great to see its still a thriving community.

I'm in the process of buying my next house - a detached bungalow with a room in the loft, that has undergone a single story flat-roofed extension.

I wish to replace/add to the single story extension by adding a pitched roof and connecting through to the existing habited roof space.

My question is - what is the best way of determining whether I can use the existing foundations/walls of the current single story extension and just 'add' the roof on, or whether I will have to demolish and re-dig deeper foundations?

My theory is single story foundations should bear the weight of a roof (ie bungalow) as opposed to needing double story foundations that would be overkill because I dont need two-stories and a roof?

Any advice much appreciated.

I should mention I haven't got the keys yet, I'm just trying to establish a plan of attack and this seems the initial and most obvious hurdle. Would save a lot of money if I don't need to knock down the existing 35m2 extension!

TIA, Deano

 

[roboughton]

some excavation to see what the foundations are unless existing people know but even then would you trust the info.

 

[r6deano]

Yes looks like a couple of pits to be dug. Unfortunately can't ask the chap that lived there, as he has passed away.

Would you happen to know if single story foundations are sufficient to support the roof as well, again depending on foundation width and depth. Or is there a guideline / table of regs that state what particular foundations will support what (based on soil types)?

 

[freddiemercurystwin]

Normally you would be OK, what age is the house and the extension.

 

[r6deano]

I think it was built '61, the extension was added 2002.

 

[freddiemercurystwin]

I expect the foundations would be fine then. But a trial hole may be required.