Is it normal for an external brick wall not to be built on top of the slab?

[ChrisM514]

Hi Guys, 

We're renovating our 1970s home and getting ready to remove some walls. 

As I'm working towards the installation of a wind column in the brick wall cavity, I've uncovered that the external brick wall is not sitting on the slab. Is this a way they did things back in the day?

Were  located in Perth 

[Jewelleryrescue]

Hi @ChrisM514 

I havent seen that building method it almost looks like a termite  control gap of some sorts?

I think  @MitchellMc  may have a few more insights on building  construction.

I do know a whole wall of single bricks  must be supported underneath by some thing solid. 

[JacobZ]

Hi @ChrisM514,

A warm welcome to the Bunnings Workshop community and thank you for your question.

I can't say I've ever seen a double brick wall built like this, but it may have been considered an acceptable method of construction in Perth in the '70s. You'd likely need to speak with a building inspector or someone who was building brick homes in your area during that timeframe to get solid answers. 

Modern double brick homes are built on a single slab with a reinforced edge beam running around the perimeter where the walls are located. If the walls are built on different slabs as you suspect, this would not be possible. 

If you brush away the soil at the bottom of the cavity, is there concrete underneath, or is it just soil all the way through? If there is concrete at the bottom of this cavity, it may still be one slab with a step-up. 

If you can get access to the original building plans, this could shed some light on what is going on.

Allow me to tag @Nailbag, @Dave-1 and @ProjectPete for their thoughts.

Let me know if you have any further questions.

Jacob

[Dave-1]

Good Evening @ChrisM514 

Im thinking that the two walls have been built at seperate times. 

Its only a theory But the bricks look like they are different sizes as well as the mortar kind of looks differant? If its on a foundation footing then it should be solid.

BTW what is a wind column? I havnt heard of the cavity with that name before?

Dave

[Nailbag]

Hi @ChrisM514 

This type of construction in the early 60-70's was too uncommon in WA when the original home wasn't built double brick as an after-build to provide an additional layer of insulation against the heat. Hence why the outer wall is not built on the original footings. To know for sure, you could take @JacobZ advice and see if the original plans are n record withe the local council. There will be a fee from $20 to $50 for an electronic copy that you will need to apply for.

Nailbag