Anyone built over a single storey extension?

[Mn753]

Hello, we have a large kitchen extension (done before we moved in). If we built above it we could add another bedroom or two. Has anyone done anything similar, and would they recommend?

We are link detached, about 1m attaches to next door then detaches again.

TIA

I think you would need to get a professional to check the foundations and build of the existing extension to see if it could take the weight of an additional storey.

Plus you would probably need planning permission too.

you will need to get foundations checked to make sure they are suitable for a second floor - they may not be deep enough ( get a structural engineer to check ) you could check whether the original plans where for 2 floors

@cricketball

I think you would need to get a professional to check the foundations and build of the existing extension to see if it could take the weight of an additional storey.

Plus you would probably need planning permission too.

Exactly this, it depends n your existing footings, unless they are deep enough to carry the extra load you would need to tear down your existing and start from the foundations again, you need to dig a test hole next to your existing and get an architect, engineer to checked depth, you may not need planning as depending on the size this may now come under permitted development, you would still require building regs which would cover the requirements for the correct depth of foundation

How long ago was the extension built? If it was recent, it may be possible the foundations might be enough. If it was decades ago, given by the experience of neighbours, I'd say you'd be looking at demolition and rebuilding, which gets very much more expensive than doing the job without there being an extension there. (Our neighbours gave up on the idea after getting quotes). Having said that, neighbours of friends of ours have done just that, the garage (in their case) is now demolished and they are starting to dig out new foundations.
You used to be able to build over on steel 'legs' but I think that option went a long time ago!

Thanks all, I'm not sure how long ago it was built. The back of the house was a hodgepodge of outbuildings that got tidied up 10 years ago but I don't know how much was new.

Really helpful advice thank you, similar houses with more bedrooms would be around 150k so theoretically should be cheaper than moving but will ask some professionals what they think.

We can cope now with bedrooms but wfh has added strain and thinking ahead to teenagers who won't want to share a room!

Yes we did build over. Have to expose at least the corners of each building to check the foundations and depth. In addition, don't forget to check that the external wall skin is double skin as if not then you have to rectify it and have the foundations to support it