Garden Wall Failure

[Doug99]

Hi all,
I have a 17m x 1.7m single brick garden wall which has failed for a length of 3m at one end. It looks as if the cement has failed at the 3rd course and the upper part of the wall has shifted approx 2cm. I have a couple of queries:

1. If the 3m section is to be rebuilt,should I rebuild from the 3rd course up, or rebuild from the foundation?
2. The coping stones along the full 17m also need replacing. How do I remove the old cement from the top face of the wall without damaging the brickwork bond?

PS - I'm seeking advice on why it failed, but there is no evidence of subsidence as the lower courses remain true and level.

Cheers

 

[KenGMac]

Doug99, good evening.

There are several distinct variables going on here, I suppose that is what you are looking for?

1/. The original mortar mix has a bearing.
2/. The state of the mortar and has the wall been re-pointed and overall generally maintained.
3/. How many brick piers are incorporated into the wall, and at what centers, [if any]
4/. Crucial is have you any idea of the age of the wall?

There is a very high probability that the simple action of wind on the wall will have possibly occasioned the movement? is the wall highly exposed, or? is the damage opposite a configuration of adjacent properties that allows wind to be funneled on to the wall?

Another possible cause, if someone on the other side of the wall used the wall as a goals and pounded the wall with a Football??

OK, I am now going to "come clean" I work "Freelance" as a Subsidence Engineer "So called, in Insurance terms for insurers and Loss Adjusters"

I have been asked to inspect dozens of failed / failing garden Boundary walls [not covered under any Insurance policy, unless the main property is damaged at the same time and by the same cause as the damage to the wall]

Most common cause of failure I have inspected is 2/. above? the Boundary wall has not been maintained, IE re-pointed

As for your second question, how to remove the old mortar? Suggest you undertake this task carefully, a "Bolster" and a light weight hammer?

One thing to consider? do you "own" this damaged wall?

Ken.

 

[Doug99]

Thanks Ken for your reply.
The wall is over 14yrs old (since I moved in) and I do know the previous owner built the wall to replace a fence after 1990 (house build).
The mortar is sound and no signs of any other mortar cracking or coming away anywhere.
The wall has shifted outwards (from my garden) so it hasn't been impacted by anything from the other side.
I reported the failure after a period of stormy weather.
I had an insurer assessor visit today who took a few pics and then emailed to say that the failure cannot be attributed to any 'single event'!!
The failure is tucked away in the corner of my garden so only noticeable when standing up close. My explanation that I only noticed it recently after stormy weather was not sufficient as I was honest enough to say that it could have occurred earlier. (Ive been with the same insurer since 2010) Unfortunately the wall is still standing. If it had toppled when it failed it seems I would have stood a better chance with my claim. I am not aware of any insurance T&Cs to stipulate that we are required to closely inspect all boundary walls after a period of windy weather so I am a bit miffed at the moment.
Just waiting for the insurance company to confirm their position before I raise my concerns.
Cheers

 

[KenGMac]

Doug99, Good morning.

Another problem you may encounter is that there is a clause in all policies, no matter who the Insurer is that states something like.

"Wear and tear" or Long term operating cause, this bit of the fine print means that something that deteriorates over several years is not covered under the T&Cs

As you have stated, if the wall was blown over then yes there is a day date and time when the insurer can say Yes the wind speed was above [generally] 55 MPH [This speed is the "Generally" accepted wind speed that allows a claim for Storm to be intimated]

But is hat wind velocity was not attained then the Insurer will recoil behind the Wear and Tear / Old Age clause and reject the claim.

Let the board know how you get on?

Ken

 

[^woody^]

If the wall has moved sideways, and the end is unrestrained, then wind, impact or a physical force are the possible causes. The crack at the connected end will be the tell-tale.

The condition of the horizontal joint where it failed will also tell if there were contributing factors from damp, frost or settlement, design or age. Its also common for walls to fail on the DPC if one is fitted

You need to know your precise insured conditions to be able to claim against them, or at least word your claim and associate the damage with the policy conditions. Your loss adjuster must surely have given you his reasons as to why the wall failed, and now you can counter those. The loss adjuster is unlikley to be qualified in construction pathology, and if he is not, then he can't comment on why the wall has failed (he just gives unqualified opinion which is worth jack) and you can, if you think its worth it, get a suitably qualified expert to report on the cause of failure.