London/ SE. Did you renovate recently? Need help with budget estimate

[sellotape12]

If anyone has done an extension and refurbishment in London recently (2021-23), I would love your perspective. We’re trying to work out how much cash to put aside from the sale of our current house for renovations.

1930s semi totalling 133 m sq including loft. So.
upstairs needs

• new bathroom (approx 7.5m sq)
• new windows to the back
• re-plastering of bedroom walls x3 rooms
• New architraves x4 doors and skirting boards

downstairs needs
• knocking the kitchen & dining into one and adding 3.5 meter extension. We would most likely need to use an architect too. The extension would be about 17 m².
• assume adding modern glazing like sliding doors to the extension
• new kitchen, units and appliances.
• new flooring to the entire downstairs and ideally an underfloor heating system. So total downstairs area of 51 m²
• converting 2 existing cupboards into a downstairs loo

What should I be allowing for this? Assume mid to nice level, nothing ultra high end.

We’ve just done the second exactly. It cost us around £150k. New kitchen and appliances were another £50k on top. We did splurge on authentic Crittal French doors (£13k) and a large roof light. I won’t lie, it hurt!

Beware of extra costs that aren’t included in the initial quote. Planning fees, drainage inspections, fixing bodges that have been hidden for decades. Every little change will cost time and money and you need to think about the cost of tiles, flooring, paint etc.

SE London.

Ha this is also SE London. Thanks so much @ghislaine is it ok to clarify?
Did you mean 150 + 50 = £200k? And did you also mean to add planning fees, drainage, crazy curveballs on top of that too? And did you use an architect? Sorry - so many questions!

We did all of the above bar the extension (and architect). London. £100k.

Yes, £200k all in although we didn’t use an architect as the extension was a simple one, just a box on the back of the house and converting the existing kitchen into a utility and downstairs loo. The original builder’s quote was around £100k. We had quotes ranging from £70k to £130k for the work alone.

There is a builder/labourer shortage at the moment, driving up wages and there have been massive increases in materials like cement and steel since the pandemic as well.

I know someone who has had an extension downstairs, not massively huge but boxing off their kitchen. No fold doors, new flooring kitchen etc landscaping small garden, and a new bathroom

200k

zone 3 London

@Namedmyself oh wow, that actually troubles me because I think the maximum can we could go to would be 150k. I agree there’s a trouble with labour shortage and the cost of materials going up though

@ghislaine great thank you. Oh golly gosh I don’t think we can afford 200 K.

That would eat too much of our deposit and our mortgage loan would need to be higher. Also, I didn’t realise that you could do an extension without an architect. I assumed they were essential to the design and planning. What kind of level of drawing or plan do you need to give a builder without an architect?

A fairly simple drawing is all that’s needed. You can do your own if your project falls within permitted development rules and you’re not planning some Grand Designs project. We used a company called Resi whom I wouldn’t recommend as they weren’t very responsive but essentially you can use an “architectural technician” rather than an architect to put something together. I would draw something up on a piece of A3 and then show it to builders that you have in to quote.

We did pay quite a bit for the fixtures and fittings because we wanted a very particular look. For example, non-Crittal French doors would have been around £4k. Our countertop was moulded as one curved piece - that was £5k. Our bathroom tiles we wanted a particular shade of green that was only done by one company in the UK, etc etc. You can definitely save money by going with more standard options and for a long time I looked at various secondhand kitchen websites before realising the look I wanted wasn’t going to crop up as bargain of the day. Ditto for various salvage sites.

@ghislaine honestly can’t thank you enough for sharing all of this. And sounds like you knew exactly what you wanted. So respect to you for sticking to it. It is your home after all. It’s something that you spend every day in!
yes, a couple of friends of ours found a secondhand and beautiful Poggenpohl kitchen that some rich a couple in West London had just thrown out..!

We are SE London/ Kent border. We have a 1930s semi too and have completely renovated it since 2020, and have just about finished loft conversion too. I can’t remember the exact breakdowns without checking, but plastering was extortionate. Kitchens can be as much or as little as you want dep on spec. We used Diy kitchens.

I would happily recommend our builder and architect if useful, please PM me for details.

I was going to say you won't see much change from £200k and see others are saying similar.

We just did the second part of your proposed work. 3.5m extension with no underfloor heating. All in it cost us 150k incl. architect fees and planning fees. To manage the budget we went high end on some things (sliding doors and worktops) and budget on others (DIY Kitchens). We also had to rent an Airbnb for some of the time which added another 8k. What we found is that the steelwork for the open plan space added a huge amount to the overall cost. We are in London, zone 4.

We are in york, currently about 2/3 of way through a project not dissimilar to yours, and it's costing us the best part of £250k.

We do have some very large steels though, but still seems eye watering to me. Ours was based on the best value of several quotes.

@ethelredonagoodday oh wow that does seem an awful lot. Is it a big house or are you doing something architecturally quite stunning? Good luck with it all.

Thanks @Dogsandbabies I really appreciate your perspective. I think 150k would be the absolute top of our budget with contingency included. So maybe that means we would have to sack off the bathroom and upstairs doorway/skirting as well as underfloor heating. We are London zone 3. It’s really scary how much labour and materials costs have increased.
May I ask what your experience of using an architect has been like? Do you think it’s worth the money in terms of managing the project and the budget and your stress levels?

The architect was absolutely not worth it in my opinion. If you know what you want I would have a look at the online planning portal of your council and get a basic plan drawn up. You will need a structural plan but that is required post planning permission and I should have asked my builder for a recommendation on who he works with. Also to note that we were very lucky our builder stuck to budget. Our builder cost 100k for a first fix and only went over by 3k. The rest were all the add ons, kitchen, cloakroom, tiles, floors, internal doors and sliding doors. We did all the painting and skirtings.

It was very expensive but we have been using the space for a month and we really love living in it. So for us it was worth it.

I should have added we are SE London too

@sellotape12 we completed something similar excl ground floor extension incl full rewire, new heating system, no UFH cost us around £240k including appliances.

We used an architect. We completed march 2022 (started November 2021). We likely paid more for the speed as lots of contractors/builders on site at the same time.

We started with a 3bed/1bath +downstairs loo1930s semi with garage (c.1500sqft) and ended with a 4bed/2bath +downstairs loo +utility room +garage (c1650sqft)

London, Zone 6

I don't think £150k will get you far. You basically need to pick between the loft extension and the ground floor and extension

It's an Edwardian double fronted semi, but the extension isn't full width and other than wanting to not have a column in the new extension, I would say, is nothing particularly out of the ordinary. Like you is 3m extension, with rooflight, glass sliders, underfloor heating and new kitchen/utility and downstairs loo. We are having some outbuildings rebuilt (think coal shed and wash house type thing) and some patio put down, plus some canopies over outside space to create sheltered outside seating, so that will have added to the cost and you might knock off £50k for that? I just think everything is so expensive at the mo.
We were hoping to do loft conversion too out of the same funds and there's no chance any of the quotes would have covered that. 😵‍💫

Sorry just jumping on this thread as we're renovating, wanting to extend the downstairs and add a utility and bathroom. We paid £10k for our tiny en suite upstairs, renovated the bedroom, plastering, new carpet, we did the skirting ourselves. This was about 4K but that includes our new lovely super king size bed.

@Dogsandbabies would you mind sending over who you worked with?

P.S. were in SE London, zone 4.

I agree with others, £200-£250k. We spent more than this but we went higher end and also did the loft. Glazing is so expensive. Our sliding doors cost £12k.

We are also London Zone 3.

I think if I were you I’d get the upstairs sorted (but do you really need all the re-plastering, most of the time you can fill and repaint or paper?) and then think about doing the downstairs but without the extension- so just knocking the kitchen diner together and doing the downstairs loo. Chances are you could do the extension in the future. Then you’d do it for your budget. There are a couple of episodes of love it or list it where people have just reconfigured houses internally and it worked really well.

Or as others have said get the extension and downstairs loo done if you think that will make a massive difference and then gradually do everything else when funds allow.