How to check footings of old stone house?

[Brockk]

I live in an old semi that has thick stone walls (with 3 x brick on party wall). It has two floors when looking at it from the front and three when looking at it from the rear - the basement is on the same floor as the garden.

The basement is on two different levels as they were originally two rooms, and I'd like to make it all one level. I am guessing these old houses didn't have proper damp proofing etc so I am thinking about ripping the old floor out and putting in new to regulations (one part of the floor has damp rising through it anyway, hence another reason why I am considering doing it).

My question is how do I check footings in an old stone house? Most of the videos I've seen are for brick houses. I plan to dig in the middle of the room on the stone wall side, but how will I know where the footings start? Does anyone have any photos they could share?

Also would anyone know how much room I will need (so I can work out how much ceiling height I'll have - if it'll mean I will be left with shorter ceiling height then I won't bother as it's not got great headroom to begin with). I found this but it gives no measurements:

If that's between 5-10cm hardcore, 10 insulation and 10 concrete, should I allow for 30cm?

 

[blup]

At least, plus screed and finished floor. Theres a lot of materials to be taken out and brought in, plus the structural implications of tne existing footings and removal of the internal wall, and potential issues around damp proofing basements. Additional costs if a listed building.

 

[^woody^]

The only way to check footings is to dig a hole next to them and look.

A floor slab for a basement does not necessarily need to be the same thickness as a floor slab at ground level. It depends on the ground type and condition.

You do need to be careening careful when excavating adjacent to walls and their foundations, and any new floor slab may need additional design consideration for that alone.

 

[Brockk]

Thanks both, though I'm getting worried now! Should I just leave it? I don't want to uncover problems.

removal of the internal wall,

This was done at least 10 years ago, a steel beam was added.

damp proofing basements

Front wall (the wall that's underground) has been tanked, tho could either do with being done again, or, as one of my neighbours has done, build another brick wall in front of it - any thoughts on that?

A floor slab for a basement does not necessarily need to be the same thickness as a floor slab at ground level. It depends on the ground type and condition.

Any links with further info on that?

Anyone know of any YouTube vids showing how to check footings of stone houses?

 

[blup]

Front wall (the wall that's underground) has been tanked, tho could either do with being done again, or, as one of my neighbours has done, build another brick wall in front of it - any thoughts on that?

Thats a specialist area but from what i know water pressure is water pressure and it will find its way through, so if it is, or becomes, a problem, a sump or drainage system is needed.

 

[cdbe]

The only way to check footings is to dig a hole next to them and look.

Anyone know of any YouTube vids showing how to check footings of stone houses?

If you need a you tube video to dig a hole I wouldn't be starting this project. I presume you're trying to see whether the foundations are deep enough to lower the internal floor? Get your spade and crack on.

My picture shows the basic principle of what you can do near foundations without engineering input.

You're unlikely to find a concrete strip under yours, maybe a wider "plinth" arrangement or just built straight off the ground. But only one way to find out!

 

[Notch7]

And old stone house is pretty likely to have no foundation at all

 

[bernardgreen]

And old stone house is pretty likely to have no foundation at all

I can confirm that. My old cottage (( C17 cottage, formerly a pair. Limestone rubble and thatch, )) has no foundations, It ad built on compacted earth and over the first few years the weight of walls compressed the ground even more.

 

[Brockk]

I presume you're trying to see whether the foundations are deep enough to lower the internal floor? Get your spade and crack on.

Yep. As mentioned I have seen lots of videos where the walls have been brick, but none where they were stone

And old stone house is pretty likely to have no foundation at all

This is what I was concerned about...

I can confirm that. My old cottage (( C17 cottage, formerly a pair. Limestone rubble and thatch, )) has no foundations, It ad built on compacted earth and over the first few years the weight of walls compressed the ground even more.

What did you end up doing?

If I don't have 30cm, can I forgo the insulation and just make do with DPC? My guess is there is just a concrete slab here

 

[bernardgreen]

What did you end up

I ended up living in it. And enjoying the life.

 

[Notch7]

I can confirm that. My old cottage (( C17 cottage, formerly a pair. Limestone rubble and thatch, )) has no foundations, It ad built on compacted earth and over the first few years the weight of walls compressed the ground even more.

It’s amazing how well these old houses stand without moving for hundreds of years.

of course traditional building practices with lime mortar were much more forgiving of movement than cementitious based mortars and plasters which crack at the slightest hint of movement

 

[bernardgreen]

It’s amazing how well these old houses stand without moving for hundreds of years.

But they do move, in most cases not enough to worry but a few have had to have tie bars added to keep the walls from tipping ( to far away ) from vertical.

 

[Brockk]

I just remembered I took a photo of my neighbour's basement a while back, does it give you any clues? I'd be happy with the room height they've got: https://i.ibb.co/7gW0LkK/IMG-0095-2.jpg" alt="IMG-0095-2