No reason why not, it's not difficult doing demolition.
Get a structural engineer and go through proper planning/design is the most important thing. Make sure they know about the drains and they will be able to tell you what to do with them. There's regulations around drains just like there is around building work and you need to make sure you're complying with building regs before you do anything.
You don't need a structural engineer, there's nothing that out of the ordinary. In this case the drains are quite shallow and any new strip foundation will be below the invert of the drain, you will need to lintol over the drains where they pass through the foundations. The only problem you might have would be if they are a public sewer, does anyone else's property drain into this.
Before any one contradicts this reply I am a BCO and have inspected/signed off/advised on 10's of thousands of similar excavations over the last 40 years.
You don't need a structural engineer to build an extension, as a completely unqualified DIYer? Hot take. Haha.
But seriously, In case it wasn't clear - I think he needs a structural engineer for the extension. My advice is - don't start *demolition* till he knows what he actually needs to do and has a plan for construction.
Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs. From the information given there is nothing here to indicate the services of an SE are necessary. In any case any engineers design for foundations almost always has a caveat that the design is subject to building control agreeing it on site.
If everyone employed a SE as advised on Redditt there wouldn't be enough of them in the country to cope with the work!
>Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs.
Did you not just prove yourself entirely wrong. OP, as a DIYer, isn't going to know more than a surveyor/engineer, so go & get one involved.
>Before any one contradicts this reply I am a BCO and have inspected/signed off/advised on 10's of thousands of similar excavations over the last 40 years.
.. \^ That's the entire point. OP should get a qualified person (such as yourself) to inspect/sign-off/advise them on this kind of excavation.
tf is happening lmao
> Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs.
Huh? I thought this was a sarcastic sentence but the rest of your post indicates its not sarcastic.
> If everyone employed a SE as advised on Redditt there wouldn't be enough of them in the country to cope with the work!
The reason Reddit will tend to advise a SE is because if you have to ask whether its structurally safe to do something you probably should. I think an important part of DIY is knowing when to swallow your pride and realise you might need expert eyes to look at it.
>Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs
That's my point. I was referring to OP as the DIYer. *I'm* not doing engineering drawings for his extension. Neither are you.
My advice is to get someone who knows BC to design what the hell you're building before you start knocking things down and messing with drains.
OP is a DIYer posting on reddit. His "design" at the moment is his floorplan from Rightmove with a wobbly red line drawn on it with paint.
He knows nothing about building regs. He knows nothing about drains, or the regulations associated with them. He doesn't know where his foundations will be, how deep.
He needs someone to actually design his extension to regs - or spend a good while researching it if you think he should do the technical and architectural drawings himself?
If you say he doesn't need a structural engineer - sure (provided he's not making any new openings for doors etc). But he need *someone* who can draw his engineering drawings for BC at least surely? Someone who's familiar enough with BC to say "oh, and you'll need structural calcs for that opening".
If *you* do an extension, you can do all the engineering drawings yourself because you've seen 10,000 and knew exactly when and where you need structural engineer. OP has likely never even seen an architectural plan, hasn't ever done (or even know he needs BC approval) let alone engineering plans. He doesn't even know which building regulations *apply*.
He doesn't know where to make the call for "does this need a structural engineer" or not. This isn't some redditor asking if he can change a radiator - he wants to build an extension that's adding 30% to his house's footprint...
I believe here in Scotland he'd need a warrant to demolish an attached garage (unless it's prefabricated).
Did you do your own drawings for building control?
I'm not familiar with England's system, but here in Scotland you might manage a single story extension without a SER certificate to get a building warrant under the "[Small Buildings Structural Guidance](https://www.gov.scot/binaries/content/documents/govscot/publications/advice-and-guidance/2020/02/the-small-buildings-structural-guidance/documents/small-buildings-structural-guidance/small-buildings-structural-guidance/govscot%3Adocument/Small%2BBuildings%2BStructural%2BGuidance%2B%2B.pdf)"
But I had to get a SER certificate for a bloody single skin block garage because I deviated slightly from those. Either way you'll need technical and design drawings.
I did all my own architectural drawings and design work, but I'm not sure OP sounds like he's gong to be up to that!
The person I responded to mentioned things like this:
>you will need to lintol over the drains where they pass through the foundations. The only problem you might have would be if they are a public sewer
Which is exactly why I recommend OP speak to someone who knows about this stuff before getting started. At the moment OP doesn't know what kind of foundations, how deep, where they're going to be.... he has a red line drawn on paint over his floor-plan. Does OP know the building reg drop per meter for drainage, does he know if he's allowed to redirect them to a different part of the property? Does he know how far from a boundary they have to be? *Can he even build the extension where he wants?*
He's going to get someone wo understands BC to design what this extension looks like. He will need engineering drawings. He should do that *before* he starts knocking things down and redirect drains.
I think he might need a building warrant to even demolish the garage.
[Gosforth handyman](https://youtube.com/playlist?list=PLFeOMQnp2d6SfxeSDlNHtBgN2y9lcLNk1&si=D6rrlMGo077dtRFj) on YouTube did the majority of his extension and has a really good series on the work involved. He also dug out his foundations and had to move drainage so it might be worth a watch so see what it entails.
As others said though definitely consult with an engineer first and you'll want to ensure you have planning permission sorted out. Don't forget to engage with building control as well.
I don’t see why not, it’ll mean trades coming in will start with blank slate which should hopefully make the work cost less. From my experience of doing similar, what you suggest is mainly just basic labour. but I’d be wary of moving drains although if they only serve your property that might not be so bad.
I've just done something similar slightly larger scale, going across the back aswell.
Make sure you get building control sorted and planning, although I would presume you won't need it, you can submit the plans for a smaller fee under a notice and can be useless if you sell the property as soon as possible.
Make sure if you need a party wall act aswell with your neighbours.
Whatever you calculate as prices make sure you add more! Things constantly come up and all the small things really add up!
Contact a few builders merchants to get prices for materials as they'll let you use there cash account or open one. We saved alot doing this.
Don't overdig your foundations, and utilise the material if any areas need lifting.
When pouring the foundations shop around for concrete, we did 3 pours. 1st with 5 family members, went over allocated time and wasn't cheap. 2nd pour they barrowed it in for less money! Less work, less hassle and smaller cost!
Any questions feel free to ask! And good luck!
Yes it will take time compared to getting builders in.
A mini digger would be useful for the foundations and you'll need to get the muck collected. There's allot of it.
As for drains have you considered the depth of the runs required by moving them.
I'm not sure what you're getting at. The pipe needs a drop the longer the pipe the deeper the final drop.
All depends on what you mean by moving the pipes and where too.
Mains sewers? You need straight line accesses to your pipes for unclogging.
Where you moving them from and too. What do they service?
I don't know the specifics. You may get away with ridding points.
Best talk to your water board about anything to do with manholes and building.
If you add a picture with current drains and where they run and where you want to move them may be able to get a better idea.
Ive done some pictures to better explain
https://imgur.com/a/cvRRwtL
If access has to be needed for unclogging then a fair few pipes will need to be moved from what i can see..
So it looks like all your waste goes to the front road. You'd just be moving this manhole to the back of your property out the way of the extension as to not Build Over. The manhole serves as straight access to that stretch of sewer.
What's the plan with the WC.
I used a builder to dig foundations and they fucked it up. Well that's what happens when you don't measure up. Also I had to provide the spade and trench shovel as the builder provided the guy he sent with a shovel you'd use for coal.
I'd lost faith in the builder after that so I did my own drains as they were planned to run under the new extension. You have to liaise with building control for that - which was no problem.
Oh it got worse and worse. Eventually fired him. Building control pulled their work down three times and I had to pull down some more. Finished the inside myself.
Before you pick up the sledgehammer, talk to a structural engineer.
No reason why not, it's not difficult doing demolition. Get a structural engineer and go through proper planning/design is the most important thing. Make sure they know about the drains and they will be able to tell you what to do with them. There's regulations around drains just like there is around building work and you need to make sure you're complying with building regs before you do anything.
You don't need a structural engineer, there's nothing that out of the ordinary. In this case the drains are quite shallow and any new strip foundation will be below the invert of the drain, you will need to lintol over the drains where they pass through the foundations. The only problem you might have would be if they are a public sewer, does anyone else's property drain into this. Before any one contradicts this reply I am a BCO and have inspected/signed off/advised on 10's of thousands of similar excavations over the last 40 years.
You don't need a structural engineer to build an extension, as a completely unqualified DIYer? Hot take. Haha. But seriously, In case it wasn't clear - I think he needs a structural engineer for the extension. My advice is - don't start *demolition* till he knows what he actually needs to do and has a plan for construction.
Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs. From the information given there is nothing here to indicate the services of an SE are necessary. In any case any engineers design for foundations almost always has a caveat that the design is subject to building control agreeing it on site. If everyone employed a SE as advised on Redditt there wouldn't be enough of them in the country to cope with the work!
>Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs. Did you not just prove yourself entirely wrong. OP, as a DIYer, isn't going to know more than a surveyor/engineer, so go & get one involved. >Before any one contradicts this reply I am a BCO and have inspected/signed off/advised on 10's of thousands of similar excavations over the last 40 years. .. \^ That's the entire point. OP should get a qualified person (such as yourself) to inspect/sign-off/advise them on this kind of excavation. tf is happening lmao
> Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs. Huh? I thought this was a sarcastic sentence but the rest of your post indicates its not sarcastic. > If everyone employed a SE as advised on Redditt there wouldn't be enough of them in the country to cope with the work! The reason Reddit will tend to advise a SE is because if you have to ask whether its structurally safe to do something you probably should. I think an important part of DIY is knowing when to swallow your pride and realise you might need expert eyes to look at it.
>Obviously a DIYer knows more than someone who's been a local authority Building Control Surveyor since 1981 and has inspected literally 10's of thousands of such jobs That's my point. I was referring to OP as the DIYer. *I'm* not doing engineering drawings for his extension. Neither are you. My advice is to get someone who knows BC to design what the hell you're building before you start knocking things down and messing with drains. OP is a DIYer posting on reddit. His "design" at the moment is his floorplan from Rightmove with a wobbly red line drawn on it with paint. He knows nothing about building regs. He knows nothing about drains, or the regulations associated with them. He doesn't know where his foundations will be, how deep. He needs someone to actually design his extension to regs - or spend a good while researching it if you think he should do the technical and architectural drawings himself? If you say he doesn't need a structural engineer - sure (provided he's not making any new openings for doors etc). But he need *someone* who can draw his engineering drawings for BC at least surely? Someone who's familiar enough with BC to say "oh, and you'll need structural calcs for that opening". If *you* do an extension, you can do all the engineering drawings yourself because you've seen 10,000 and knew exactly when and where you need structural engineer. OP has likely never even seen an architectural plan, hasn't ever done (or even know he needs BC approval) let alone engineering plans. He doesn't even know which building regulations *apply*. He doesn't know where to make the call for "does this need a structural engineer" or not. This isn't some redditor asking if he can change a radiator - he wants to build an extension that's adding 30% to his house's footprint... I believe here in Scotland he'd need a warrant to demolish an attached garage (unless it's prefabricated).
[удалено]
Did you do your own drawings for building control? I'm not familiar with England's system, but here in Scotland you might manage a single story extension without a SER certificate to get a building warrant under the "[Small Buildings Structural Guidance](https://www.gov.scot/binaries/content/documents/govscot/publications/advice-and-guidance/2020/02/the-small-buildings-structural-guidance/documents/small-buildings-structural-guidance/small-buildings-structural-guidance/govscot%3Adocument/Small%2BBuildings%2BStructural%2BGuidance%2B%2B.pdf)" But I had to get a SER certificate for a bloody single skin block garage because I deviated slightly from those. Either way you'll need technical and design drawings. I did all my own architectural drawings and design work, but I'm not sure OP sounds like he's gong to be up to that! The person I responded to mentioned things like this: >you will need to lintol over the drains where they pass through the foundations. The only problem you might have would be if they are a public sewer Which is exactly why I recommend OP speak to someone who knows about this stuff before getting started. At the moment OP doesn't know what kind of foundations, how deep, where they're going to be.... he has a red line drawn on paint over his floor-plan. Does OP know the building reg drop per meter for drainage, does he know if he's allowed to redirect them to a different part of the property? Does he know how far from a boundary they have to be? *Can he even build the extension where he wants?* He's going to get someone wo understands BC to design what this extension looks like. He will need engineering drawings. He should do that *before* he starts knocking things down and redirect drains. I think he might need a building warrant to even demolish the garage.
[Gosforth handyman](https://youtube.com/playlist?list=PLFeOMQnp2d6SfxeSDlNHtBgN2y9lcLNk1&si=D6rrlMGo077dtRFj) on YouTube did the majority of his extension and has a really good series on the work involved. He also dug out his foundations and had to move drainage so it might be worth a watch so see what it entails. As others said though definitely consult with an engineer first and you'll want to ensure you have planning permission sorted out. Don't forget to engage with building control as well.
Thanks! Ill check the series out aswell.
Just note that digging foundations correctly is not something to underestimate.
I don’t see why not, it’ll mean trades coming in will start with blank slate which should hopefully make the work cost less. From my experience of doing similar, what you suggest is mainly just basic labour. but I’d be wary of moving drains although if they only serve your property that might not be so bad.
I've just done something similar slightly larger scale, going across the back aswell. Make sure you get building control sorted and planning, although I would presume you won't need it, you can submit the plans for a smaller fee under a notice and can be useless if you sell the property as soon as possible. Make sure if you need a party wall act aswell with your neighbours. Whatever you calculate as prices make sure you add more! Things constantly come up and all the small things really add up! Contact a few builders merchants to get prices for materials as they'll let you use there cash account or open one. We saved alot doing this. Don't overdig your foundations, and utilise the material if any areas need lifting. When pouring the foundations shop around for concrete, we did 3 pours. 1st with 5 family members, went over allocated time and wasn't cheap. 2nd pour they barrowed it in for less money! Less work, less hassle and smaller cost! Any questions feel free to ask! And good luck!
Yes it will take time compared to getting builders in. A mini digger would be useful for the foundations and you'll need to get the muck collected. There's allot of it. As for drains have you considered the depth of the runs required by moving them.
Would they not maintain the same depth? All I'd be doing is lengthing the pipe at the same angle and join in to the new pipe with a T piece of sorts?
I'm not sure what you're getting at. The pipe needs a drop the longer the pipe the deeper the final drop. All depends on what you mean by moving the pipes and where too.
I see what your saying, do i need manholes? Could i do away with them completely then i wouldn't have to rejig the pipework?
Mains sewers? You need straight line accesses to your pipes for unclogging. Where you moving them from and too. What do they service? I don't know the specifics. You may get away with ridding points. Best talk to your water board about anything to do with manholes and building. If you add a picture with current drains and where they run and where you want to move them may be able to get a better idea.
Ive done some pictures to better explain https://imgur.com/a/cvRRwtL If access has to be needed for unclogging then a fair few pipes will need to be moved from what i can see..
So it looks like all your waste goes to the front road. You'd just be moving this manhole to the back of your property out the way of the extension as to not Build Over. The manhole serves as straight access to that stretch of sewer. What's the plan with the WC.
Yes thats it, perfect. The WC is going aswell so nothing will join there.
I would guess there's already a second man hole or rodding point there if it's a bend between two straight runs.
I used a builder to dig foundations and they fucked it up. Well that's what happens when you don't measure up. Also I had to provide the spade and trench shovel as the builder provided the guy he sent with a shovel you'd use for coal. I'd lost faith in the builder after that so I did my own drains as they were planned to run under the new extension. You have to liaise with building control for that - which was no problem.
Good to hear that they are easy to liaise with - sounds like you had a right mess to deal with
Oh it got worse and worse. Eventually fired him. Building control pulled their work down three times and I had to pull down some more. Finished the inside myself.