Self build extension

[Diyextension]

Noticed a few threads on people building extensions / knocking down conservatory etc , so I’m just about to start doing mine.

I thought it might be good for anybody thinking about building one or for people that have no experience/ idea what the process involves.

i will probably be doing about 80% of the work myself , and then using certain trades , plasterer/ electrical as and when.

Old conservatory will be removed and. Single story (bedroom ) extension will be in its place. It’s 5m x 4m .

progress will be slow as I work full time so days of and holidays only.
it should be a straightforward job , but the only downside is we live on a hill so everything has to be carried up/ or down.

if anyone has any questions , feel free to ask and I’ll try to put pictures on as and when there is any progress.

Just came across this. Have so much admiration for you. I paid builders to renovate our house and the project managing and small bits of decorating were hard enough! All the best to you, can’t wait to see the progress.

Thanks all ,I’ll update when there is any progress.

another skip is booked for Friday to get rid of all the clay and I’ve messaged the bricklayer to pop round and let me know how many blocks/bricks we need to get it up to floor height. I can work it out but I’m not sure which way he wants to do it foundation blocks or 100 mm blocks and cavity fill. Both ways have pros and cons so I’ll let him decide.

it’s not stopping raining and the foundations are under water( glad I got the concrete in ) 🙂

Well it’s still raining all the time ☹️ But we have managed to clear all the clay away which was harder work than actually digging it out the ground due to it being soaking wet , sticking to everything and being twice as heavy than when it’s dry 😤. 2 phone calls and 8 days later they turned up to remove the skip, I’ve never seen a skip lorry Straining so much lifting a skip , thought the chains were going to snap 😲

On the plus side the blocks for the foundations are here and also the the bricks. We only needed 200 facing bricks to get to Dpc/ floor level but due to availability issues were advised to get all of them (2300 ). The only problem with this is they will now be in the way and will have to move them all somewhere out the way till I need the rest. So hopefully weather permitting we might see it up to floor level next week .

How is it coming on OP? I am so impressed with what you’ve achieved so far!

Ah , sorry didn’t see someone had replied on here .

Well this is as far as we have got , it’s up to the finished floor level and is ready to carry on with filling in the floor.

The concrete was pretty level so the block work was pretty straightforward, no issues really apart from the crappy weather.

budget wise it’s still looking ok, more or less on track,

Need to order the hardcore ( mot ) next to start filling the floor, need to try and get it delivered in a grab wagon and dropped on the site rather than tipped on the drive , I’m not sure getting 17tonne up the steps by hand will be a good idea 🤨.

Hi, i love your thread. Any other progress. I'd like to think I could do something similar...😊

I'm following with interest as I think we will be doing this later in the year

Loving seeing the pics on here-I looked in the summer but have just seen the thread pop up again- what amazing progress!!

No further progress, had a bit of a break over Christmas and due to the area being so wet and muddy motivation is a bit low at the minute. It just never seems to stop raining 🙁. I do need to get some hardcore down soon to try and stop the mud but before that there are some new cables ( power,cctv,alarm) to run from the house to the garage ( inside the blue bag ).

Having the walls set out now means we can work out the size of the window,the amount of insulation for the floor the amount of concrete for the floor, in fact now we have something to measure off nearly all the materials to build it can be worked out more or less exactly.

The opening into the house with the old ten Downing Street lookalike door boarding it up actually held up quite well in the cold snap we had before Christmas. Duct taped everything up inside and it kept out the cold reasonably well mind it’s about 2 inches thick and weighs a ton . 🙂

Hello nice clean white stone , goodbye mud 👋🏼

time to get something done again.

Nice! I just came on looking for updates and am delighted to see one here!
I am going to have to refit some foundations of an existing outhouse. Not bothering with building regs as it's just to stop an existing. Building from collapsing. How deep to put foundations?

Sorry, I’m not an expert on these things dystylam.

Did some shovelling and compacting today on the floor , I thought the stone that was dropped in the extension would be plenty, but once it’s whacked down it’s about 100mm too low so I’m going to have to use the pile ear marked for outside instead 😐.

im off work for a week soon so I’m hoping to get the floor finished then ( weather permitting). I’ve got the stone/ sand / damp proof membrane here just need the insulation and book the concrete/ pump.

cost wise I’ve spent a total of £6401. So far but that includes extra stone for the area around the extension and 400 extra facing bricks for a small retaining wall.

once I start on the floor I’ll try and explain in more detail ( pictures ) how it all goes together , for anyone thinking of doing the same ( similar).

Wow looks impressive!
How have you linked house and extension together?is it just build up against it or do you have to interlace bricks?

you can tooth the brickwork in, it’s quite time consuming removing all the bricks. Another way and the one I will use is stainless steel starter kits, they are metal channels you fix to the walls with wall ties that you hook on to them and then build the brickwork onto them. One channel for inside block work and one channel for the outside bricks. You can see them on the picture below.

the brickwork is then cut out between them ( 100mm) to continue the cavity and insulation to meet the one on the house.

Everything you can see so far will be mostly underground so it’s not tied into the house, The top of the block work you can see is the finished floor level/ dpc.

That’s really interesting! Thank you!

Are you completely self taught?

I’m not in the building trade, I’ve just learnt over the years by helping/ watching people. Anything I don’t know/ understand then I usually know someone who does. Once you get stuck into something it usually turns out to be simpler than you think ( technically). It’s still hard work ( physically).

you can also learn a lot on the internet now.

Amazing! I guess you have done other projects before so this was in your abilities.

Just stumbled across this. You have done an amazing job. That digging out looked like hell, clay is truly horrific to work with. We had an extension built a decade ago but I had watched a million YouTube videos and had a great builder who took time to explain everything as they went.

There is a chap I watch on YouTube called Gosforth Handyman and he has also completed a self build extension, same as you, dug out foundations etc but got a brickie who just wanted to lay bricks.

We couldn't do strip foundations, had to be a concrete pad due to being on a slope and how the house is originally built, also on a concrete pad with pillars into the earth. No way could we have hand dug it out. Luckily we could get a digger to the back. Keep at it, visualise the end result, that is what kept us going with our temporary kitchen and young children.

I’ve got a brickie like that too 🙂 he just likes to lay the bricks, no mixing ( I have my own mixer ) no labouring , no cleaning up after… but he makes a good job , it saves me money, and here for any queries that pop up. Works for us both.

So we’ve had some really crap weather this winter and has hampered the already slow progress, but I’ve been off this week and it’s been unseasonably decent weather for February. I’ve booked the concrete and pump for Saturday so come rain or shine it’s going in 🤞🏼 Quite a bit to do to get it ready, building inspector is coming Friday .

first job get the rest of the stone in

Once it’s all levelled off to the right depth, I’ve just used the two old conservatory rooftimbers screwed together to measure off. Just whacked it all down nice and flat.

Then 20mm sand on top ( blinding ) . It’s to prevent any sharp stones puncturing the damp proof membrane that goes on top.

It’s actually a lot more difficult to get the sand level than it looks , took ages as when it’s wet it just sticks to the bottom of the wacker in a lump and you have to keep stopping to scrape it off 🫤

ive started to cut out the brickwork to continue with the cavity in to the house and been to fetch the insulation and membrane, so hopefully by Friday everything will be ready for concrete Saturday.

The insulation on the car is for the floor of the extension yes?

Yes, that’s correct damp proof membrane, first thenthe insulation and concrete on top, it’s different if your having underfloor heating , but we are not.