How much does a UK house extension really cost?

So how much did our self-build extension really cost? Today we’re taking a deep dive in to the actual costs of a home extension construction project in the UK. We’ll look at what you can expect to pay per square metre along with a full detailed breakdown of exactly how much our extension cost.

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Extension Cost Chapters:
0:00 - Introduction
2:58 - Cost per square metre
11:26 - How much we paid
15:29 - Cost breakdown
22:16 - Would we do it again?

#Extension #SelfBuild #Construction

[thedigitalemotion]

The cheapest way I’ve found to get the cost down is to talk yourself out of the idea 😊

[JohnARoake]

As a retired project manager, 8 years out, I found your extention costings extremely useful in order to bring me up to date on current material costs for 22-23. I am still asked to do work and to give advice, so costwise, your advice was first class, uncomplicated and suitably brief. I commend you sir. John Roake

[benjaqsonworkshop]

Thanks for posting such a detailed spreadsheet breakdown of the whole process. It's very open and generous of you to share your costs and experiences of the build. Very helpful and very interesting. I do feel like I have a sense of investment having lived through your last four houses though now! All the best for 2023.

[colinmiles]

Thanks for taking the time to do that breakdown of costs - very useful.
And I'm glad you mentioned the costing of your own time. The trade off is your eye is always on the ball.
As some of your earlier posters mentioned, Building Regs change all the time, adding to your costs.
The great thing about being involved is that it (usually!) gets done how you want it.
I'm 67 now and have got 2 projects on the go for two of my sons. I think these will be my last
Particularly as they bought me the latest 1:24 scale Spitfire from Airfix for Xmas!

[tonydeltablues]

Very, very useful; I've forwarded this to my brother-in-law who is thinking of extending their 1930s semi in South Liverpool. Appreciate the time and generosity of sharing. Tony

[siggy_]

We're planning our extension at the moment; your breakdown is excellent and has put my mind at rest that my finger in the air costs are about right. Looking forward to your guidance on trades - normally I do everything myself but for speed and sheer amount of effort I'm considering getting blockwork and the like done by someone.

[tayyz]

Eventhought I am not planning for the extension, the amount of knowledge and insight is amazing.

[tomstroud]

Great video. I’m a builder of 20+ years running my own business and even after all that time pricing jobs is my nemesis. I hate it with a passion, each job is so different and intricate that guide line costs per m2 are sometimes very vague and I certainly wouldn’t quote based on them alone. I have always considered it as gambling really. You can so easily come a cropper by not quoting enough and nothing is more soul destroying and financially crippling like under quoting and working for free, especially as it’s a very hard job both mentally and physically.
One thing I would add is that I’ve deliberately not quoted for twice as many jobs as I’ve actually quoted for. This is because the job is comprised in some way e.g poor access, lack of room to operate, awkward neighbours etc. The number 1 reason though is because I’ve not gotten good vibes from the client. Too abrupt/rude, disorganised, unprepared for the realities of having your home turned upside down temporarily. It’s very much a two way thing. You must trust me to dismantle and rebuild the most expensive asset you will likely ever own and I have to trust you’re going to pay me for my work and be able to adapt and understand when things don’t go to plan i.e unforeseen problems and changes.
As a final thought, most of the very best tradesman are the best because they do what they do best and that’s create actual real 3 dimensional objects and installations. That means they usually, like myself, hate doing paperwork and quoting otherwise they would just get a cushty office job in the warm and dry without breaking their back for what seems at times like not enough money. I’ll stop whingeing now 😂

[kevinclark]

I did my own extension 4 years ago and came out at £26, 000 with kitchen. That was 3m x 8m with bifolds toilet and utility.
Bare in mind I only had a brickie, electrician and plasterer. Everything else I done myself including making sure building standards were met. But I've done projects in the past with work. It's not easy especially working full time as well but it's definitely worth the effort.

[olivermorrissey]

Coming from a Engineering background and having worked on construction projects for over 18yrs now, it's good to see someone breaking down a project on a residential extension.

I've done extensions and I would have at around £96k from information and sizes off your plans.

And that would be making a modest 10 to 12% I reckon.
We only work to specification and above.

Looks a nice job, well done.
Regards

[leejames]

I’ve been waiting for some time for such a detailed and honest appraisal video. Absolutely fantastic. Subscribed

[PCNxx]

It has been a great following your journey with this project. Looking forward to the next one. Well done👍🏻

[davidstorm]

Great video, really informative. We have an old (Victorian) stone-built detached house, to which we've done extensive renovations that have so far taken us 21 years, but we've done everything ourselves, except for some structural steelwork which the house needed in the cellars. One of the jobs we did was a full cellar restoration after the steelwork had been installed, this was a huge task as the cellars are full height rooms which cover the entire house footprint. I reckon we completed the work for about one tenth the cost of what it would have been if we had used contractors to do the same job, plus we probably got a higher standard of finish and everything was exactly how we wanted it. It is very hared work and very time-consuming, but you can't beat doing it yourself if you have the skills and the inclination

[pazt]

I've only come across your channel yesterday but you are definitely one of my favourite content creators! So knowledgeable and just and all around nice guy!

[laidbackLUKEY]

Thank you for taking your time and sharing this with the public, top man 👍🏻

[domsaneria]

Most insightful of all the building videos I've watched, so many about the different ways to build but no one has broken in down by doing it yourself as opposed to asking the builder. thank you

[rdtheskald]

Good thing I can do the planning myself and also build it myself, all I would need to pay for would be materials and the groundwork! It is extremely beneficial to acquire construction skills in your lifetime!

[Banshee]

Really useful information. Thanks for taking the time to go through it all. Great job 👍🏼

[moanahughes]

Wow I comprehended all of that! Your itemizing is really useful template for putting projects together to consider and maybe stagger stages of development to budget. Thanks 😊

[BischBaschBosch]

Well done mate. We mainly did large commercial/corporate jobs when I was still in it but did do a few small builds and extensions too. I just dug out my last set of builders bibles from 2009. Its m2 averages are £750 for basic going up to £980 for high spec (stone, thermal etc). We had our own formula that fell in between at the time. My earliest edition (early 00's), from £350 m2! Gone a bit crazy eh? Again though, excellent video and grand job on the extension.👍