How much to extend above garage and convert garage?

[KeepLosingThings]

How much roughly would it cost at current prices (in South East England) to convert a single garage and extend over the garage, including finishing the interiors? No bathrooms or kitchens involved. Anyone know? Thank you.

I can't help re costs as haven't done a build for 5 years and prices have gone up enormously. However, have you checked you can build above. Combination of whether the foundations are suitable and deep enough, with do you have a double skin on the garage as a lot do not!

Thank you. I am not sure (I haven't bought the house yet) but a lot of identical houses in the area have built above the garage - no idea if they had to strengthen foundations first though

Most garage walls are single skinned ie just the exterior brick, no cavity wall so the foundations might be unsuitable to take the weight of anything above. A test pit will be needed to check what foundations there are. That is the starting point. The cost of the build depends on whether you need new foundations.

Ok, thank you, useful to know. So does anyone know what that cost would be roughly (a) if foundations are already ok or (b) if it needs new foundations?

A million pounds

Sorry, can't help with your situation but doing a full house extension/refurb myself and this is what it feels like. Double our initial budget. Only a builder with drawings can tell you really, as it will depend if they need to knock down the garage and start again.

Ask one of those houses?

On a previous thread, the guide was £3,000 per M2 of usable space inside. So if it's 5 x 3 x 2 floors, then around £90,000. Possibly plus Vat.

Thank you Sewfrickinamazeballs, good idea. Hope you are pleased with your extension in the end, despite the extra cost.

Thank you for the estimate Antikythera, sounds doable if that turns out to be right - hopefully won't double again by the time I actually do it!

With prices the way they are and considering you haven't moved in yet, it almost certainly makes more sense to just buy a slightly bigger house or one that has already had the conversion done.

I see your point Furier but the problem is there is only one house on the market at the moment that is bigger and meets all my other criteria - and it costs 500k more!

We have spoken to some architects about building above current extension- even if foundations aren’t suitable, you don’t need to knock it down and start again..it just needs to be reinforced which may cost about 10-20k depending on site.
we’re in scotland and have been told roughly 100-150k to do loft conversion extending out onto current single extension as well as knocking down a wall or two.
v rough price atm and we’re trying to decide whether it’s better to wait a little while because of price increases.

Thanks Michelle. Useful to know. Would be nice to have a crystal ball and find out whether extension costs are going to keep increasing or not! Good luck with your extension plans.

There is another house on now that we could afford and is plenty big enough already. But on a busy road. There's always something!

Far more than you think!

Sorry, feeling rather helpless as our workshop (garage sized) conversion costs are spiralling.