What have I uncovered?

[PlumCottage]

Hi everyone,

I am need your help. For the past few months I have been slowly removing the cement pointing, concrete and any vegetation next to my house.

I started breaking a concrete plinth this morning and realised there wasn't any soil under some parts.
This is what I have found. The uncovered bricks look to be arched. I haven't been able to gauge the depth of the void under my house. Do I continue? Or should I stop?

Any help or guidance would be appreciated. Ravinder

 

[nicobobinus]

Coal chute?
...or sewer?!

Can you poke something like a long garden cane into the hole to measure its height & depth?

 

[Cubist]

Hi Ravinder and Welcome,
For the moment discretions advisable so stop for now. A little more information would be helpful.
Would I/we be right to assume it's a stone built house or cottage sitting on the brick foundations you've exposed?
Is there a cellar?
Are the floors in the rooms inside solid or suspended wooden plank floors? Also, why are you removing the concrete and mortar?

 

[aockenden]

Possibly a cellar. One way to safely investigate is to use a long snake camera like they use for septic or chimney inspections

 

[chrisfraser05]

I'd get a boroscope cammera for your phone from Amazon for 20 quid and have a good look.

 

[PlumCottage]

Hi Ravinder and Welcome,
For the moment discretions advisable so stop for now. A little more information would be helpful.
Would I/we be right to assume it's a stone built house or cottage sitting on the brick foundations you've exposed?
Is there a cellar?
Are the floors in the rooms inside solid or suspended wooden plank floors? Also, why are you removing the concrete and mortar?

Hi Cubist,

The cottage opens onto the pavement which has created a higher ground level outside. Foundations are stone.

A concrete path was poured down the side of the house. Which raised the outside levels leading to damp inside. We have started creating a Zebcolm Trench in an attemp to resolve.

Some of the bricks on the back wall are blown internally and externally. Hoping to repoint in lime. The internal floors are concrete.

It looks as it has been back filled with rubble.

 

[Cubist]

It looks like Nico was right in saying it's an old coal cellar. It was likely back-filled with any old rubbish when the concrete floors indoors were laid. I'm a trifle concerned by what appears to be a wooden beam or lintel and its framework. It's not clear but possibly this carried the wooden floor for the room above rather than any other structural purpose. I think you would be wise to remove some more of that rubble infill to investigate further and confirm that theory and to determine if any of the brickwork above the beam is loose and/or needs additional support.

I'm assuming the Zebcolm trench is to combat an internal damp problem? If that's the case you should consider establishing an impermeable barrier between that infill material and the trench - particularly if the slope of the pavement and traffic volumes allow rainwater to collect next to that wall.

 

[PlumCottage]

Thank you everyone. I will keep you updated on the progress.

 

[PlumCottage]

Afternoon

We have slowly removed bags of rubble to find...it has been back filled with more rubble. Tried pushing a boroscope through the gaps but it didn't get far enough to show anything.

If you look at the most recent pictures, highlighted by the green box is clear plastic. I am assuming this is the dpm for the concrete floor? I am taking a pause whilst I find a structural engineer.

Any further guidance or tips would be appreciated.

Ravinder

 

[Cubist]

Hi Ravinder,
I think that confirms it. There was a cellar and maybe a coal-chute there at some now distant time. The iron grill mounted in the timber frame you've un-earthed would have carried a lead glazed pane of glass to provide some daytime illumination inside.This probably dates the frame to maybe the Victorian period, I have a few of these that still survive here.Your work has also confirmed that the void was completely back-filled before the concrete floors were poured over the plastic sheet Damp Membrane you've exposed.

The challenge is now then - what will you do with this new hole in the ground?

Cheers,
Cubist

 

[PlumCottage]

Thanks Cubist, my interim plan is to fix a cold frame to the wall to cover the hole.

I would love to remove the concrete floor inside and reinstate the cellar but that would all depend on the condition and cost. So far one firm has said £1500 for the structural engineer to assess the underfloor, with the following caveat, "we will only undertake works at this project if we carry out all the work associated because of how complex it is".

 

[Cubist]

Thanks Cubist, my interim plan is to fix a cold frame to the wall to cover the hole.

I would love to remove the concrete floor inside and reinstate the cellar but that would all depend on the condition and cost. So far one firm has said £1500 for the structural engineer to assess the underfloor, with the following caveat, "we will only undertake works at this project if we carry out all the work associated because of how complex it is".

And that folks is the very literal definition of a 'Money Pit'! But it could also be considered a Can of Worms if you proceed with such an open ended agreement. Only you can decide how far to go but good luck with whatever you choose to do.