Hi everyone, I posted the below on a Facebook group and had a lot of greatful people thank me for the advice, so I thought by cross posting here it might also help others out.
I have recently completed a front (20sqm) and rear (30sqm) two storey extension and a single storey side (25sqm) extension, including structural alterations and knock throughs. This post isn’t to ask for advice, but to share my experience of project managing the build and doing a lot of it myself DIYer and hopefully help some of you save money if you’re also planning on having work done.
I initially went down the route of getting quotes from building companies and they were coming in at £250-350k (this was in 2022 as well!). I ended up project managing myself and spent £175k. This spend is for plastered finish, complete re plumb, underfloor heating and rewire of the house, new tiled roof for the whole house and new aluminium windows and bifolds for whole house and new kitchen
My advice:
1. Get a good architect that can see the project through from drawings, to building regs to structural drawings. A good architect will think a few steps ahead, recommend materials such as insulation (down to the specific type). This will help keep things consistent throughout the project.
2. Learn, live, breathe, study and understand every aspect of the plans, building regs and s/e drawings. You’ll 100% be asked questions by every trade and you need to be able to make decisions quickly to avoid delaying trades.
3. Get things quantified. I used Proquant. There are several others, such as the build aviator which is a service provided by jewson.co.uk. This will give you a material list and estimated prices, estimated amount of days per trade broken down by skilled labourers, labourers, bricklayers, joiners ground workers etc.
4. The materials will have a cost to them, take this with a pinch of salt and set up an account with merchants such as Parker’s - tell them the size of the project and est spend on materials and agree a discount for a trade account. You’ll be surprised how much you can save vs going to travis Perkins as Joe Public. On average I’ve saved 15% but on some things the discount has been almost 50%. Some building merchants will also offer to QS the materials for free as long as you buy them all through them. Even when you have a trade account somewhere you’ll be able to get your prices beaten. Merchants are all gunning for your business, so use something like pricenailer.com to make sure you’re getting a good deal. This site also has a very comprehensive extension cost calculator and planner.
5. Don’t worry about lining up all the trades in advanced. Unlike main building contractors who much have 6months to a year waiting time, sub contractors are usually available within a few weeks notice.
6. Don’t use checkatrade / my builder to find trades. Once you’ve found your ground workers, they’ll have good contacts for brickies. The brickies will have contacts for joiners etc etc. Build up your network and it will be easy. Try to also work with very local trades I.e within 15-30mins away.
7. I’ve sent out emails or called up around 8-15 of each trade to get best prices. Based on labour only, I had ground works quotes ranging between 16k and 42k. I went with the cheapest and they were outstanding. Knowledgable, tidy, considerate and hard working. I found my ground workers via digger hire companies - get creative!
8. Use your local authority for building control. It’s easy, and once you’ve met the inspector 50% of things can be approved / discussed over call or WhatsApp and you don’t have the risk of a private company going into administration.
9. Get a portaloo. For £25 a week, trust me it’ll be the best investment you make.
10. With buying materials yourself and only paying trades for labour, they should all be fine with paying week by week, reducing your risk to losing cash if a building company goes broke.
11. You’ll be surprised how much you spend on waste removal. Skips are pricey. If you shop around you’ll find a grab lorry willing to take 17 tonnes of utility waste for 250 cash.
12. If you want to do things yourself and you’re handy or a quick learner, skill builder have an entire series on YouTube for building an extension. In my opinion things like 1st fix carpentry (Stud walls, floor joists etc) and demolition works can all be done yourself. Leave finishing such as flooring and plastering to pros. Even jobs like laying insulation, and fitting the ufh pipes (to the plumbers spec of course) are all DIYable
13. JFDI. It’s easier to ask for forgiveness than permission.
14. Windows and doors. We had 13 new windows, 2 sets of heritage style bifolds (3 & 5m), French doors and a single door. We wanted all black aluminium and costs were coming in high. We ended up going direct to an aluminium supplier for the frames and got the glazing separately, then paid installers on a day rate to fit. For all this ended up paying £22k, almost half of some other quotes.
Pic of before and after for context!
I have recently completed a front (20sqm) and rear (30sqm) two storey extension and a single storey side (25sqm) extension, including structural alterations and knock throughs. This post isn’t to ask for advice, but to share my experience of project managing the build and doing a lot of it myself DIYer and hopefully help some of you save money if you’re also planning on having work done.
I initially went down the route of getting quotes from building companies and they were coming in at £250-350k (this was in 2022 as well!). I ended up project managing myself and spent £175k. This spend is for plastered finish, complete re plumb, underfloor heating and rewire of the house, new tiled roof for the whole house and new aluminium windows and bifolds for whole house and new kitchen
My advice:
1. Get a good architect that can see the project through from drawings, to building regs to structural drawings. A good architect will think a few steps ahead, recommend materials such as insulation (down to the specific type). This will help keep things consistent throughout the project.
2. Learn, live, breathe, study and understand every aspect of the plans, building regs and s/e drawings. You’ll 100% be asked questions by every trade and you need to be able to make decisions quickly to avoid delaying trades.
3. Get things quantified. I used Proquant. There are several others, such as the build aviator which is a service provided by jewson.co.uk. This will give you a material list and estimated prices, estimated amount of days per trade broken down by skilled labourers, labourers, bricklayers, joiners ground workers etc.
4. The materials will have a cost to them, take this with a pinch of salt and set up an account with merchants such as Parker’s - tell them the size of the project and est spend on materials and agree a discount for a trade account. You’ll be surprised how much you can save vs going to travis Perkins as Joe Public. On average I’ve saved 15% but on some things the discount has been almost 50%. Some building merchants will also offer to QS the materials for free as long as you buy them all through them. Even when you have a trade account somewhere you’ll be able to get your prices beaten. Merchants are all gunning for your business, so use something like pricenailer.com to make sure you’re getting a good deal. This site also has a very comprehensive extension cost calculator and planner.
5. Don’t worry about lining up all the trades in advanced. Unlike main building contractors who much have 6months to a year waiting time, sub contractors are usually available within a few weeks notice.
6. Don’t use checkatrade / my builder to find trades. Once you’ve found your ground workers, they’ll have good contacts for brickies. The brickies will have contacts for joiners etc etc. Build up your network and it will be easy. Try to also work with very local trades I.e within 15-30mins away.
7. I’ve sent out emails or called up around 8-15 of each trade to get best prices. Based on labour only, I had ground works quotes ranging between 16k and 42k. I went with the cheapest and they were outstanding. Knowledgable, tidy, considerate and hard working. I found my ground workers via digger hire companies - get creative!
8. Use your local authority for building control. It’s easy, and once you’ve met the inspector 50% of things can be approved / discussed over call or WhatsApp and you don’t have the risk of a private company going into administration.
9. Get a portaloo. For £25 a week, trust me it’ll be the best investment you make.
10. With buying materials yourself and only paying trades for labour, they should all be fine with paying week by week, reducing your risk to losing cash if a building company goes broke.
11. You’ll be surprised how much you spend on waste removal. Skips are pricey. If you shop around you’ll find a grab lorry willing to take 17 tonnes of utility waste for 250 cash.
12. If you want to do things yourself and you’re handy or a quick learner, skill builder have an entire series on YouTube for building an extension. In my opinion things like 1st fix carpentry (Stud walls, floor joists etc) and demolition works can all be done yourself. Leave finishing such as flooring and plastering to pros. Even jobs like laying insulation, and fitting the ufh pipes (to the plumbers spec of course) are all DIYable
13. JFDI. It’s easier to ask for forgiveness than permission.
14. Windows and doors. We had 13 new windows, 2 sets of heritage style bifolds (3 & 5m), French doors and a single door. We wanted all black aluminium and costs were coming in high. We ended up going direct to an aluminium supplier for the frames and got the glazing separately, then paid installers on a day rate to fit. For all this ended up paying £22k, almost half of some other quotes.
Pic of before and after for context!
