Possible internal subsidence

[Hitesh]

Hi - we live in a detached house in Harrow (NW London) which has a solid concrete floor. We have subsidence showing in various internal walls but nothing can be seen on the external walls.

My insurance company had declined the claim as we have a solid concrete floor which was davastating. My questions are 

1)Has anyone heard of claim declined due to solid floor? If yes, what are the reasons for this? (I am waiting to hear from my insurer on this)

2)I am looking for a good structural engineer to help me with the whole project - any recommendations?

Thanks in advance

Harish

 

[Nickfromwales]

Challenge the insurance company and ask for full written reason for the refusal.

 

I’ll PM you some details for an SE near you. Another member is using them and good feedback so far. 

[saveasteading]

1. No. That is nonsense. But If there is more wording than that then please tell us all. Then when /if you hear more too.

2. Do you have any construction drawings to show the SE? That can help speed things along.

 

3. Insurance clerks are generally not remotely knowledgeable on construction. Some companies reject almost everything to see if that gets rid of the claim. 

I met one insurance senior manager of a big company, who bragged how little they paid out... It seems to be a published % comparing insurance companies as a money making exercise, not any sort of service ethos.

 

What age is the house?

[Hitesh]

Thanks both for your prompt responses.

The wording from policy document is - "we wont pay claims for 

Damage to solid floors, or damage caused by solid floors moving. We’ll pay these claims if the foundations

underneath the outside walls are damaged at the same time and by the same cause"

We have underfloor heating installed about 7 years ago when the solid floors were done. The damage seems to internal walls only and external walls seem to be OK. I can ask the SE about this, I suppose.

No drawings available.

[Redbeard]

18 hours ago, Hitesh said:

We have underfloor heating installed about 7 years ago when the solid floors were done. The damage seems to internal walls only and external walls seem to be OK. I can ask the SE about this, I suppose.

 

Ooh err...

 

How long had you had the house before you had the UFH?

 

What were the floors before? What footings did the internal walls sit on?

 

If you were in the house for a while before you had the UFH done it suggests some 'parameter' has been (inadvertently) changed.

[Hitesh]

Thanks

We had the house 20 years before the UFH was installed.

Wooded floor prior to installation of UFH.

Would the solid concrete  floor done at time of UFH installion put additional pressure on the internal walls?

TIA

[Redbeard]

I am not thinking of the floors putting pressure on the walls, but whether the change in floor structure in any way 'undermined' the internal walls. As it was suspended floors before that does not seem likely, as each wall would have its own foundation. As I asked above, what ('footings') foundations did the internal walls have?

[Hitesh]

I am afraid I have no idea.

The house is approx 100 years old, if that may give clues.

[-rick-]

Do you have any photos from when the work was being done?

[Hitesh]

Afraid not

[saveasteading]

Can we see photos of the walls where the damage is?

 

Do you think the walls are loadbearing (supporting upstairs rooms) ? Were they there when you moved in?

 

Generally 100 years ago it would be brick construction on concrete trench footings. and would have moved before now if it was going to. Also for the internal walls to subside but not the externals is unusual.

 

Any big trees nearby?

 

Does the floor appear to have moved?

[Redbeard]

On 06/10/2025 at 16:00, Hitesh said:

We have subsidence showing in various internal walls but nothing can be seen on the external walls

 

Have you had a structural engineer's report?

22 hours ago, Hitesh said:

"we wont pay claims for 

Damage to solid floors, or damage caused by solid floors moving. We’ll pay these claims if the foundations

underneath the outside walls are damaged at the same time and by the same cause"

You could argue that this quote means that you are not covered., but this covers damage to floors, and refers to external walls. You have an issue with *walls*, not floors! If you have not had an SE report do get one, and ask the insurers to tell you why they *won't* pay out.

[Hitesh]

Photos attached - the cracks are around 1mm wide.

The wall where most of the cracks exist was the original external wall before an extension was built about 35 - 40 years ago. So it goes all the way up.

There is a bay tree about 3 meters away and an ash tree about 12 meters away.

Yes the floor (of the extension) seems to be sinking.

I am waiting for the formal letter from the insurer - once I have this, I will show this to SE and get their report.

Thanks for taking the time to read and respond.

[saveasteading]

How big are the trees? 

 

I think the ground is usually clay round your way but you or someone else local may know.

Big trees on clay can be  a problem.

This sounds like subsidence from trees sucking water from clay ground and the hot summer combined, which shrinks the clay.

 

But it's odd that external walls are not affected. Maybe they are but you can't see it. Are they brick?

 

I'm pretty sure this is not because the slab has failed, so insurance should cover it.

 

You must get this looked at by an SE.

[Hitesh]

Thanks

The external walls are brick with rendering.

Will get a SE soon.

[saveasteading]

50 minutes ago, Hitesh said:

brick with rendering.

That should show any cracking.

 

I wonder if there is any way these internal wall were added later, and built on the floor slab.  That may not be insured.

When you brief the SE be sure to tell them this is re an insurance claim.  If the SE thinks the problem is not the original foundations then you may wish to drop the claim and minimise his report and fee.

That wouldn't resolve the original issue of course, but that can follow.

[Hitesh]

Noted - thanks all for your comments