House underpinning

mizzbonita

Hi

I need some pointing done at the front of my house and have had several quotes. The builder that came today said the front needs underpinning as it’s sinking on one side. I see what he means and I’m now stressing about it. I looked it up and the last thing I want to do is claim via insurance for this as it will be a nightmare to insure after. Also I’m not sure how it would work because it’s two flats and we both have buildings and contents insurance. 

From the pictures, could anyone give me some advice please. Does it need underpinning? 

mizzbonita

Front of the house 

Doozergirl

You need advice from a structural engineer,
but there's something going on there.  

pramsay13

Maybe, you need a structural surveyor.

When we bought out 1820s house there are no straight lines and there are a few bits like this. Our structural survey said that movement was historic and there was no sign of recent movement.

The window area wasn't square when the windows were fitted, how long have they been in?

FreeBear

When the repointing is done, you should really use a pure lime mortar (no cement). You have what looks like a soft red facing brick and solid wall construction. Slapping cement in there will eventually cause the bricks to spall and wreck the ability of the wall to breath.

Underpinning will involve having to dig up the concrete - That will give you opportunity to find out why the bay is sinking (a drainage issue perhaps). Don't forget, underpinning is a notifiable work and should be signed off by Building Control - Having the paperwork will make it easier to sell the property in the future... Up to you if you want to go down that road.

stuart45

Looks like it could be an issue with the rainwater drain. Bays usually fall away from the house when the foundation was shallower than the main house one.

mizzbonita

Thanks everyone. 

I’ve been here 11 years and it has always been like this to be honest. The only reason I looked at getting repointing is because I had slight damp on an internal wall which I think is coming from the drains being blocked. They are being cleared next week. 

One builder then mentioned underpinning. 

The windows have been in for at least 15 years 

Alter_ego

I see a crack above the window on right side, also is that a crack showing through the render right of the drainpipe?

mizzbonita

 No that one isn’t a crack to the right of the pipe.  

It has been like this for a number of years but I will get a structural surveyor in to check it out. 

Doozergirl

I would aslo get a CCTV survey of your drains.  You may find the culprit.  
 

FreeBear

mizzbonita said: The only reason I looked at getting repointing is because I had slight damp on an internal wall which I think is coming from the drains being blocked.

So the injected DPC and associated waterproof render/plaster internally hasn't fixed the damp.... No surprise there.

The crack either side of the stone sill is quite likely the primary cause of any damp internally. Get that fixed, and along with the repointing, much of the damp should disappear. Removing the concrete from the front, reducing the soil level, and putting in a french drain will also help. The original DPC would typically be in the mortar joint just above or below the air brick - Certainly not where some wally has been drilling holes.