I would square it off and replace the windows and single door with a sliding door to the garden. You would have to weigh up if you would gain enough space to warrant the cost of building works and a new kitchen. I would not move it into the lounge as moving the services would be very expensive and you would lose a large sunny living room. Before you decide see how much extra storage/worktop space you would gain by extending to make sure it is worth it. Could you widen the whole kitchen rather than just squaring it off? This would give you far more options.

The quoted cost seems high considering how little extra square footage you gain. It’s high because you have to change a lot of the steel structure previously put in. Consider if you would rather spend the same on a bigger extension where you just add extra behind the garage. Alternatively what about converting at least part of the garage?

Converting garage was immediate plan but ceiling quite low in there so wouldbt work well for kitchen. garden not that deep so wouldnt really want to go too far back

I would just extend further out. £20000 for such a small gain is not worth it.

Yeah i dont think we can extend further so will park the idea and embrace small but functional kitchen

The only other option is to go sideways into your lounge and make it one big kitchen, dining family room. It could look really good.

Is your garage used as such? (car or mere storage?) And is it single storey? Because a roof can be raised if there's nothing above it.

Theres a bedroom and en suite above the garage so roof cant be raised. we’re going to get garage properly insulated and converted to a utility at back, storage at front. weve a decent size drive (3 cars fit) and corner plot with a good 4/5 metres to border at side, but as garden not that deep at back, and garden east facing with large side area south facing, its a good outdoor space to keep.

i dont think we’re going to extend, its choice of keepinh as is (just doing garage into utility to move washing machine/tumbler/ironing board etc into there and free up space in kitchen), or knock through to make big lounge diner.

with knock through though, still not sure what to do with galley bit in kitchen