Concrete slab under a pole house

[Meehole]

You realise that your timber piles are sitting on concrete foundations that are exposed and if there was a land slide or earthquake your house will probably collapse?
I can't believe that you were allowed to buy it like that or that your bank has loaned you money with the piles exposed like that? I bet if the insurance assessor came around your insurance policy would be closely looked at.
Christchurch has liquefaction but Auckland suffered last summer from shrinking ground that caused many houses to slump and foundations to crack.
I would hurry up and get that sorted asap before a 3rd party finds out and that will require an engineered design now, if you can an engineer willing to put their name to it.

[elguapo]

You realise that your timber piles are sitting on concrete foundations that are exposed and if there was a land slide or earthquake your house will probably collapse?

How can you tell the effective depth of the concrete pile from a photo?

[Meehole]

How can you tell the effective depth of the concrete pile from a photo?

The concrete under the timber pile is what the pile is concreted into. Initially the concrete would have been covered by soil but it has been cut back and exposed. There is no retaining wall there either to hold the ground up where its been cut away. House piles are usually put into holes 450w x 450w x 450d and sometimes 450 x 450 x 600d depending on what an engineer has specified or if just to building code.

[elguapo]

Yet, there is well over 600mm exposed. How do you know they don't go down another meter?

One of my houses is similar and the piles were designed with them deep enough to allow for excavation and development into that area. They were over 1800mm deep from the original grade.

[Wayne]

However far they still go down they now go down the amount shown less than they did.
They were the depth they were for a reason - now it is less!
I would be very concerned if it was mine.

[elguapo]

However far they still go down they now go down the amount shown less than they did.
They were the depth they were for a reason - now it is less!
I would be very concerned if it was mine.

And again, you can't say there is an actual problem without finding out what the effective depth is. A quick look on the property file should show the constructed depth and see if there is any reason for concern.

[Wayne]

And again, you can't say there is an actual problem without finding out what the effective depth is. A quick look on the property file should show the constructed depth and see if there is any reason for concern.

Fair enough - at the very last they should look at the property file and hope that the detail is there (hope that the build isn't too old).

[Meehole]

And again, you can't say there is an actual problem without finding out what the effective depth is. A quick look on the property file should show the constructed depth and see if there is any reason for concern.

Well easy fix, get a building inspector from the local council out there to check. If the excavation was submitted to Council and consented then no problem, however if the previous owner has dug out in anticipation of putting in a garage underneath without completing the relevant paperwork then someone is in deep doggy doo!
Guys that do house inspections don't often allow to consult the Council files in their report but if they are any good they will have bought the unfinished work to the attention of the person they were writing the report for, or should have. If the work was done illegally there will be nothing on the property file.

[Meehole]

Yet, there is well over 600mm exposed. How do you know they don't go down another meter?

One of my houses is similar and the piles were designed with them deep enough to allow for excavation and development into that area. They were over 1800mm deep from the original grade.

If you have a look at the concrete under the pile to left of the photo you will see that it is on a slope (possibly because its falling over). That indicates their is a fairly good chance there's not much more below the soil level.
The holes look like they have been dug out with a post hole borer instead of hand digging the NZ 3604 building code requirement of 450 x 450 x 450.

[Davo36]

She'll be right guys!

Only one of them in the photo is falling over (left hand side), that still leaves 2 and man, they over-engineer these things at the start don't they?

[Meehole]

She'll be right guys!

Only one of them in the photo is falling over (left hand side), that still leaves 2 and man, they over-engineer these things at the start don't they?

What engineer?? The one out of the cornflakes box?

[elguapo]

According to the OP, it's been checked by a building inspector and someone recommended by the inspector. I would hope that either would have been able to identity a 'falling over' pile as being a problem that needs quite rapid attention, esp. as these are concrete encased. One poor quality photo simply isn't enough to make any kind of judgement on.

[Maccachic]

I wouldn't assume anything there are plenty of case where people have relied on a pre purchase report only for the "inspector" to have failed to identify some major defects.

[Meehole]

According to the OP, it's been checked by a building inspector and someone recommended by the inspector. I would hope that either would have been able to identity a 'falling over' pile as being a problem that needs quite rapid attention, esp. as these are concrete encased. One poor quality photo simply isn't enough to make any kind of judgement on.

There's a reason that guys doing building inspections have changed jobs and moved away from that as a source of income. Insurance compliance costs are huge due to the fact that if they miss something in the report and there is a problem that should have been identified during the inspection and wasn't noted they are liable.
If they missed the "falling over pile" during the inspection then I can only assume that that their seeing eye dog didn't sniff it out either. Who was the building inspector?

[ryanstev]

I've been speaking with the real estate agent I'm buying this house from and he's informed me that the previous owners (well, current owners, technically as it's not in my name yet) recently paid $27,000 to have the house repiled, he's got documents, which I haven't seen yet, which confirm this all.
I have the agent on record, via email, telling me about the work done, to council specifications, and that he'll get the documents showing the work that was done.

Now in saying that, there's no way these exposed foundations look new, but I have the agent on record, he works for a large real estate company, so there will be recourse if he's not being honest.

I've had a foundation guy around too and he wasn't really very concerned with the foundations, obviously they needed to be fixed, but he thought it was all straight forward.