Do I need a surveyor?

[Screwdriver]

I think I do. I am helping a neighbour with their half finished basement conversion. Looks like the original builders scarpered. Apart form the pool of water (more of which later) which has been sitting there for a couple of years, there's a gap, unsupported, dug out of the bare clay "foundations".

I'm a teensy bit worried that could just collapse. I might be wrong about that, I just don't know.

Quite a shock just to see it sitting there. The only reason the "pond" isn't as scummy and mosquito infested as the rest of the site is that rainwater just pours in. And when it pours in, it runs out into the base of that unsupported clay wall! The rest of the basement is tanked.

You can see the layer of gravel which is an old river bed on which the clay is deposited. I guess that would act as a decent soakaway but it worries me that it could eventually wash out the base. Am I wrong? I know there are cowboy builders around and these things can and do collapse!

Top left of the first picture you can see a walkway. An unsupported 6.5m span which has rotted out. I ripped up the boards with my bare hands. The owner had no idea that drop was under those boards (despite falling through the one over the main area). I should get danger money. It's pretty sketchy at best.

 

[Pete.]

That wall of clay is just sitting there waiting for some unsuspecting victim to come near it.

 

[slim_boy_fat]

You wouldn't get me down there.

 

[Screwdriver]

How bad is it?

 

[Screwdriver]

I offered to help clear the site until I spotted this:

Which I said I'd fix asap!

They had no idea that was unsupported and rotten. Death trap frankly. There are rebar spikes everywhere...

 

[brightspark]

clay is in layers any ingress of water and it can all cave in .I had it happen in a pit I dug in my garage before it got shuttered and concreted

 

[WorkshopChris]

I offered to help clear the site until I spotted this:

Does the row of reinforcing rods running along the boundary, stick out of a concrete retaining wall?

 

[Screwdriver]

Does the row of reinforcing rods running along the boundary, stick out of a concrete retaining wall?

Yes. All the way around.

 

[WorkshopChris]

Yes. All the way around.

Thats good so at least their problem is not about to become your problem. Do they have the original plans and engineers calcs? Might help you work out whats going on.

 

[Rig Pig]

I'm amazed it's still standing!

 

[Screwdriver]

Thats good so at least their problem is not about to become your problem. Do they have the original plans and engineers calcs? Might help you work out whats going on.

I only offered to clear the rear garden, then I said I could replace some of the rotten boards. The basement is nothing to do with me but now I need to build a better bridge over that pathway. Theres a ton of rebar rusting gently in the garden I can have, plus a fair bit of wood and other bits and bobs. I feel I need to insist he gets someone to support that bank of clay though. Even to my untrained eye it looks well dodgy.

 

[Screwdriver]

For the record, I am suggesting something like this:

At the very least. I need to be able to ferry a load of crap from the back garden to a waiting skip.

It probably needs 4m (?) acrow props but I am not familiar with hiring or buying those items.

 

[knighty]

what's the hole under the walkway for ? windows to let light in ?

and what's the other one for ? only think I can guess is that's where the stairs to upstairs were going to be ?

 

[Screwdriver]

what's the hole under the walkway for ? windows to let light in ?

and what's the other one for ? only think I can guess is that's where the stairs to upstairs were going to be ?

I don't know. The rear extension wall is built on that chunky concrete "beam" which I note has a huge I beam inside it. There are stairs in the other corner, I'm assuming the dodgy gap is where they were just about to install stairs inside the existing kitchen.

 

[Screwdriver]

Here's the stairs to the basement from behind the house, leading from the garden.

Which after a few years, looks like it's moving in!

Note all the rebar left sticking out. It's dangerous out there.

 

[wristpin]

Get the local authority building control dept involved.

 

[Parm]

For the record, I am suggesting something like this:

At the very least. I need to be able to ferry a load of crap from the back garden to a waiting skip.

It probably needs 4m (?) acrow props but I am not familiar with hiring or buying those items.

How wide is the gap? Bit difficult to tell from the pictures.

If not too wide is it an option bolt say 2 x8 to concrete wall then run joists at 400 mm centres to an opposing timber. Using speedy hangers or similar. 18 mm ply on top. Will eliminate the second layer of joists (if ive got the drawing correct) and acro props etc

 

[Screwdriver]

The white part of the bridge is the proposed addition, goodness knows what I am supposed to stand on while I'm building it mind. I was hoping to fix a beam as shown with a couple of rawl bolts but it's all only temporary until they get the builders back (new ones) early next year. They want to get into their back garden as do I.

I am wary of drilling into anything in case the house falls down tho.

 

[Parm]

Ok, I get it now. Not a very wide gap.

I'd go with your plan. Looks like the concrete beam is adequately holding up the wall (unless I'm missing something)

Consider studding set into that resin type fixing stuff to hold timber against concrete. It won't put on load/stress like those bolts that expand.

 

[angellonewolf]

i would remove it after you finsh its ok as your using it but leave it there and i fails in a few months when a poste goes over it could cause a problem