What budget would you want for this project?

[Muuuuuuuum]

If you've done similar, or are in building trade, would appreciate any insight into approx costs for the following:

Single storey extension, replacing old lean to kitchen.

Architect plans and Planning already done.
Engineers / technical drawings still needed

Demolition of old building
3 steels required
New extension will be c. 5m x 4m
Refurb of existing rooms totalling 28 m sq
Underfloor heating for all
2 sets of French doors
New kitchen and appliances (good high street rather than bespoke / top end)
New flooring (engineered oak probably) through new and refurbed areas

We are not in London/SE but do live in a property hotspot so builders likely to be on the more expensive side.

DH doesn't want to do work unless we can pay from savings so trying to gauge how much more we'd need as I am sick of living in a wreck.

I am planning something similar, though a little further behind than you (currently waiting for architect plans). No idea how much it might cost yet which is worrying. Our architect says pricing is more unpredictable now than it's ever been because of lack of builder availability, plus materials prices are volatile and ever-climbing

50k but it really depends on fixtures & fittings & whether any problems are uncovered during the building work.

Yes, had heard that too, which worries me.

But also think we are likely to have to wait a year for a builder so worth getting one booked in - we can keep saving still and hopefully supply issues, whether Covid or Brexit related, will have settled down by time we start.

But maybe that is just wishful thinking....

50k would be amazing @imamule

I do worry what might be uncovered in a Victorian house though. But guess if we made sure we had a big contingency fund it would hopefully be ok.

I have heard that average cost of extensions is around £2,200-2,500 per sq m, so you'd be looking at £44-50k just for the extension part, and depending on the kitchen spec, you'd probably need to budget to spend £75k to include everything.

Mine was probably conservative & the absolute minimum.

We have just started some building work for a really similar project. It’s £55k and we aren’t having new doors, underfloor heating, engineered wood floor or top end appliances. I’d guess £75k for yours.

100k

Demolition of old building
3 steels required
New extension will be c. 5m x 4m
I'd say at least £2k plus VAT for the above, so rounding to £50k
Refurb of existing rooms totalling 28 m sq Depends how extensive - plastering/ painting/ lighting £5k
Underfloor heating for all Guessing £8k?
2 sets of French doors £3k
New kitchen and appliances (good high street rather than bespoke / top end) £20-25k depending on size / appliances / worktops etc
New flooring (engineered oak probably) about through new and refurbed areas So about 50sqm - about £6k?

So I agree with a budget of about £100k with a contingency.

You haven't factored in decorating and any costs for your garden which is likely to need money spending on it once it's been trampled by workmen.

£2k plus VAT per square metre!!

We did similar but in a rural area where prices are reasonable (forest of Dean) and only one set of patio doors and no underfloor heating. Totalled £42,000 after being told it would be £33,000. This was in 2015. I suspect in a booming area in today’s prices and with underfloor heating £60k would do it. I will say my husband laid the travertine floor throughout himself which saved £2k in labour.

We were quoted £28k to replace a lean to room (2.5x6m) with a side extension just to shell stage, no kitchen or electrics and plumbing etc. I’d definitely think £75-100k to get yours finished.

Thanks all. We have £110k so feel like we're in a good place (although garden will be an issue afterwards, although probably something we can tackle ourselves if no budget left).

Now just need to persuade DH...