Making use of a void under the house - Advice Required
Discussion
Hi all
I put this on another forum but received limited help. So over to PH Community!
Be patient I'm not a builder and a total novice!
Our house is about 35 years old and built on a hill. Therefore to get into the garden you go down some steps at the rear of the house. (The front of the house is level)
The rear of the house has a dining room and kitchen. The kitchen is always significantly colder than the rest of the house. So today I got a bricklayer to cut out some bricks at the rear of the house to inspect the void beneath to see if it was insulated.
When we removed the bricks the void is around 9m x 3m and roughly 2m or more in height. The kitchen floor appears to be done with concrete beams and blocks with the internal floor wayrock and LVT ontop.
The thought we had was to put a composite door in the outside wall giving access to the void. Add insulation to the concrete blocks and beams. Level the soil to create a better foundation to put a timber-suspended floor or concrete down. Then use the area for storage as it seems a waste to not use the space. And the shed is due to be replaced.
Im sure its not as straightforward as I have said and may be better with an alternative base.
I have zero idea of cost involved and of course no DIY skills at all
I have attached photos I took
Guidance appreciated. Including thoughts that this will be a money pit of an idea!
I put this on another forum but received limited help. So over to PH Community!
Be patient I'm not a builder and a total novice!
Our house is about 35 years old and built on a hill. Therefore to get into the garden you go down some steps at the rear of the house. (The front of the house is level)
The rear of the house has a dining room and kitchen. The kitchen is always significantly colder than the rest of the house. So today I got a bricklayer to cut out some bricks at the rear of the house to inspect the void beneath to see if it was insulated.
When we removed the bricks the void is around 9m x 3m and roughly 2m or more in height. The kitchen floor appears to be done with concrete beams and blocks with the internal floor wayrock and LVT ontop.
The thought we had was to put a composite door in the outside wall giving access to the void. Add insulation to the concrete blocks and beams. Level the soil to create a better foundation to put a timber-suspended floor or concrete down. Then use the area for storage as it seems a waste to not use the space. And the shed is due to be replaced.
Im sure its not as straightforward as I have said and may be better with an alternative base.
I have zero idea of cost involved and of course no DIY skills at all
I have attached photos I took
Guidance appreciated. Including thoughts that this will be a money pit of an idea!
Edited by Anastie on Saturday 4th February 16:27
From the ground to the block & beam floor only looks to be about 1.3m?
It would cost a fortune to underpin the foundations, reduce dig, tanking membrane & lay a floor in there to be of any great use.
If you really need the space you could just install a hatch/small door to keep a lawn mower in there or something.
It would cost a fortune to underpin the foundations, reduce dig, tanking membrane & lay a floor in there to be of any great use.
If you really need the space you could just install a hatch/small door to keep a lawn mower in there or something.
Anastie said:
Our house is about 35 years old and built on a hill.
The fact that the void is as high as you say tells me that it is extremely likely that at least one of the walls will be retaining part of the slope. If you want to convert it to habitable space, you'll need to tank it, if you want to prevent serious damp problems and/or water ingress. The reason they will have left it as a void when they built the property is that this is an expensive and defects-prone thing to have to do.
Are you sure about the '3m. or more in height' though, becuase counting brick courses on your photos is telling me different (at least at the shallow end, and your foundations won't go much deeper to allow you to excavate that out).
Speak to an expert.
PH.sausages said:
From the ground to the block & beam floor only looks to be about 1.3m?
It would cost a fortune to underpin the foundations, reduce dig, tanking membrane & lay a floor in there to be of any great use.
If you really need the space you could just install a hatch/small door to keep a lawn mower in there or something.
Thanks for taking the time to reply. We can't get in to give an exact measurement. But at the point where the brickie took out some bricks, he thought it was around 2 meters (I've spotted the typo and I wrote 3m)It would cost a fortune to underpin the foundations, reduce dig, tanking membrane & lay a floor in there to be of any great use.
If you really need the space you could just install a hatch/small door to keep a lawn mower in there or something.
If as you suggest if it would need lots of work we will just get an access door in to store some garden equipment.
I'm open to listening to advice from people more in the know than I am.
Very interesting find, we have a similar void at the back of a cellar, back of house like yours lower than front.
I’m looking to open up the entrance and lintel above the gap to create a garage.
Levels are also too high, so will need to excavate and maybe also underpin, although the raised floors are made of very loose material.
Due to costs, I’m planning to make the changes in stages as money allows, with the ultimate goal of making the space habitable.
Up to that point, the space can be used for storage etc in the meantime.
Regards the tanking comment, if it’s just one side of the house that’s facing into the hill, it’s not as drastic as trying to seal a full cellar.
Based on where you are, contact a few cellar conversion specialists regards options and they can guide you. Beware of any quick fix damp proofing solutions as invariably these will fail, look at the regs and investigate false wall membranes that let the water flow round and out of the building without impedance.
We bought our place knowing the space was there but also with some understanding of how much the costs could run to, web says budget £1K to £2K per metre squared to make habitable, less for storage space, more if underpinning might be required etc.
Personally the wasted space down there makes me want to do something, but go in with your eyes open!
I’m looking to open up the entrance and lintel above the gap to create a garage.
Levels are also too high, so will need to excavate and maybe also underpin, although the raised floors are made of very loose material.
Due to costs, I’m planning to make the changes in stages as money allows, with the ultimate goal of making the space habitable.
Up to that point, the space can be used for storage etc in the meantime.
Regards the tanking comment, if it’s just one side of the house that’s facing into the hill, it’s not as drastic as trying to seal a full cellar.
Based on where you are, contact a few cellar conversion specialists regards options and they can guide you. Beware of any quick fix damp proofing solutions as invariably these will fail, look at the regs and investigate false wall membranes that let the water flow round and out of the building without impedance.
We bought our place knowing the space was there but also with some understanding of how much the costs could run to, web says budget £1K to £2K per metre squared to make habitable, less for storage space, more if underpinning might be required etc.
Personally the wasted space down there makes me want to do something, but go in with your eyes open!
Effectively you have an extra 1/4 to 1/3 of floor area you can add to your house with, by most standards, minimal effort and expense.
You will probably need a lintel and pillars either side of the door you have cut, given what the wall is supporting above, and digging down to give extra headroom will mean the foundations are losing some support on their internal face.
A structural engineer is probably your first port of call, together with a look at planning regulations to see why the original architect & builder did not exploit the space to add value to the property when built.
Following a trip to Canada in the early 1960s, my father was so impressed by the basements that most houses had there, that when he built his house in the UK, he designed a basement in, which went under the whole house and garage. Like yours, it was fully underground at one end and at ground level at the other. With the central heating boiler in the basement, it was warm in the winter and being mostly underground, cool in the Summer. The only downside was that in heavy rain, a very small water would seep though the wall at the fully underground end.
My brother has a lockable space very similar to yours under his house in Australia, and he uses it 'as is' for storing his windsurfer, hang glider and trials bike. It also provides a home to some spiders I'm very glad we don't have here.
Edited by GliderRider on Saturday 4th February 16:40
That is a remarkably clean hole the builders left behind. Couple of odd bricks and that’s it, normally the lads fill it up with crap as they are going along
Deffo get the doorway put in, very low cost and gives you access for insulation and for future maintenance even if you don’t use it for anything else.
As for utilizing the space there a lots of possibilities, as others have said first port of call would be a structural engineer to ascertain what is possible and why it wasn’t done when the house was built. Tanking the below ground walls is reasonably straightforward with a product like a Sika tanking slurry.
AFAIK there are no building regs concerning ceiling height so given your pictures show around 2M of existing headroom it would seem highly likely that you could get a floor down and still have something quite useful. Can you get a window or two in anywhere? I love these quirky little voids. So useful. Good luck and keep us posted.
Deffo get the doorway put in, very low cost and gives you access for insulation and for future maintenance even if you don’t use it for anything else.
As for utilizing the space there a lots of possibilities, as others have said first port of call would be a structural engineer to ascertain what is possible and why it wasn’t done when the house was built. Tanking the below ground walls is reasonably straightforward with a product like a Sika tanking slurry.
AFAIK there are no building regs concerning ceiling height so given your pictures show around 2M of existing headroom it would seem highly likely that you could get a floor down and still have something quite useful. Can you get a window or two in anywhere? I love these quirky little voids. So useful. Good luck and keep us posted.
Grans bungalow was built like that, someone had already put a door in to keep garden gear in, proved useful when selling the property after she died, buyers surveyor wanted to knock off a few grand because the lounge floor was 'bouncing' and could have dire consequences, he'd never bothered looking underneath.
Chap my dad knew went under and put some packers between the joists and pillars, sale went through at the asking price.
Chap my dad knew went under and put some packers between the joists and pillars, sale went through at the asking price.
Keeping this thread updated.
Builder has inspected the void and will price up Insulating the roof, concrete floor, and access door outside, matching the flags in the garden when the shed is removed and electric. Got the usual sharp intake of breath from him saying it was a big job as he would have to dig down 6-7 feet to get the required height. As previous estimates of the height in the void were wrong.
Once I get a price I will share it and any additional comments or suggestions from the builder. The builder is trusted as he has done work for other friends and family. He is also fully booked for 12 months lol.
Builder has inspected the void and will price up Insulating the roof, concrete floor, and access door outside, matching the flags in the garden when the shed is removed and electric. Got the usual sharp intake of breath from him saying it was a big job as he would have to dig down 6-7 feet to get the required height. As previous estimates of the height in the void were wrong.
Once I get a price I will share it and any additional comments or suggestions from the builder. The builder is trusted as he has done work for other friends and family. He is also fully booked for 12 months lol.
Interesting.
I spoke with a builder yesterday as the flat roof on our porch has sprung a leak, so we're using it as a prompt to lose the sliding glazed door and have it bricked up, new conventional door put in, and a loo if possible at the same time.
He asked me if it had foundations. Like you OP, I have no idea!
But we're on a hill as well and there's a drop from our porch down to nextdoor's path into her garden. So I wonder if we're similar to yours under ours.
Alas, we'd have no way to make use of it as the only access we'd be able to put in would be from her garden path. Though we've been trying to work out where to put a home office . . .
I spoke with a builder yesterday as the flat roof on our porch has sprung a leak, so we're using it as a prompt to lose the sliding glazed door and have it bricked up, new conventional door put in, and a loo if possible at the same time.
He asked me if it had foundations. Like you OP, I have no idea!
But we're on a hill as well and there's a drop from our porch down to nextdoor's path into her garden. So I wonder if we're similar to yours under ours.
Alas, we'd have no way to make use of it as the only access we'd be able to put in would be from her garden path. Though we've been trying to work out where to put a home office . . .
Our house in on a hill that slopes in two directions and from road level to either the front or back door there is a difference of about 10m (at a guess) Our garage is actually directly under the kitchen and I am convinced that if I knocked through the back wall i would find voids under the rest of the house - not sure how I would go about actually finding that out though!
simon_harris said:
Our house in on a hill that slopes in two directions and from road level to either the front or back door there is a difference of about 10m (at a guess) Our garage is actually directly under the kitchen and I am convinced that if I knocked through the back wall i would find voids under the rest of the house - not sure how I would go about actually finding that out though!
Drill a hole then pop an inspection camera through! https://www.toolstation.com/draper-wi-fi-endoscope...
simon_harris said:
Our house in on a hill that slopes in two directions and from road level to either the front or back door there is a difference of about 10m (at a guess) Our garage is actually directly under the kitchen and I am convinced that if I knocked through the back wall i would find voids under the rest of the house - not sure how I would go about actually finding that out though!
We got a friend of a friend to remove enough bricks to poke your head through and have a look. Hence the photos. This also gave the builder today enough room to be able to measure the height.Having said that. Matching bricks on a 30-plus-year-old house has proven impossible. So the hole when closed up will be a mismatch and I would have gone down the inspection camera route first!
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