Thread: Advise about house movement/cracking problem

Too right about carefully removing the concrete using diamond saw. Certainly won't be allowing the use of jack hammers or the like.

As well as not wanting to disturb the interior plasterwork the exterior stone work is Mt Gambier stone which is a very soft material - it wouldn't take well to the vibrations from a jack hammer.

Hi T/O. I was wondering. Was a 'wacker-packer' used to compact the base for the pavers?
If so, I reckon the vibrations may have unsettled the soil from around the porch pad, and then along with some water, which would have been applied to the area before paving was completed, would have caused the soil to re-settle again following all the vibration.
I experienced exactly this condition on an old house a few years back, but I didn't have the concrete roof to worry about either, and the front pad dropped about 50mm along the front edge where the pavers were laid. I had to remove ALL the pavers and underpin the slab and start again. Second time round, all was well (4 years later), and as far as I know, still is.
Whatever the cause, the advice regarding settling sounds pretty right, and propping the concrete roof section makes sense.
I'm only repeating what others have already stated, so please accept my best wishes, and I hope it's a simple solution for you.
Don't you just love this site? I wish I'd found it much sooner.

Yep, the paving contractor did a few passes with a whacker to compact the road base and settle the pavers into the bedding sand. This has probably assisted in destabilising the slab.

Of interest is the fact the steel post was only connected to the concrete roof via a thin bed of mortar. As a result the post was able to come away fairly easily. If it had been screwed or bolted together the post may not have come away and the downward movement of the slab may have caused more severe damage to the stone and plasterwork.

However I'm pretty much certain now that the concrete roof has been the cause of long standing problems with cracking in that part of the house. There's evidence of repairs to the plasterwork of the adjacent interior walls which was done well before the drought and the pavers went down.

Although I'm 'not happy Jan' that it's going to cost me a few $$ to get it fixed if it resolves the long standing problem of the cracks I can certainly live with that.

Originally Posted by Timed Out

Although I'm 'not happy Jan' that it's going to cost me a few $$ to get it fixed if it resolves the long standing problem of the cracks I can certainly live with that.

That's the important thing in the long run.

I'm glad for you that it has turned out to be a relatively simple (if $$$) fix. It could've been far worse. [phew!]