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Weep holes should be positioned at the minus one course, not on the footing.
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Many builders and engineers still incorrectly place them at the lowest point.
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Placement is clearly defined in NCC, AS3700, and AS4773 standards.
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Misplaced weep holes can cause moisture retention and future damage.
Hi, I’m Russell McCarthy, lead building inspector and founder of WA Building Inspections servicing Perth. Let’s settle this once and for all: if you think weep holes should sit right on top of the footing, you’re flat out wrong. It’s not just my opinion – it’s clearly set out in the NCC, AS3700, and AS4773. Checkout my unedited video:
What is a Weep Hole and Why Is Its Placement Important?
Weep holes are small openings placed in brickwork to allow water that accumulates within a wall cavity to drain out. If placed incorrectly, water can accumulate and cause internal moisture issues, brick deterioration, and even structural damage.
“Weep holes being at the base of the footing. So for those of you believe that the weep hole should be right on top of the footing, flat out you’re just wrong.”
Where Should Weep Holes Be Placed?
In short? One course above the flashing, at the minus one course from the base of the brickwork, not directly on the footing.
“It should be either a full perpendicular up to the height of the slab or it should be on the minus one.”
This isn’t just a best-practice recommendation – it’s referenced in the National Construction Code (NCC) and enforced through AS3700 and AS4773 (deemed-to-satisfy provisions).
Why the Common Argument is Flawed
Many builders and even inspectors argue that water should drain from the lowest point. But here’s the catch:
“If the argument is water drains at the lowest point, you’re completely missing the point.”
Water that hits a footing can get trapped if the area is boxed in by hard paving or slab edges. That makes the lowest point functionally ineffective.
Example of Proper Execution
“This builder, fantastic. There’s the footing, there is the weep hole.”
In this build, the weep hole was placed at the correct height. Despite what an engineer may argue about the soil being free-draining, the physical context (hard footing and hard paving) overrides theory.
Why So Many Get It Wrong
“The engineer might come along and say, okay, well, you know, this is free draining… but there’s a footing over here, which is hard, and the pave is hard.”
Some building professionals are simply going off past habits or flawed assumptions. Even worse, some can’t answer simple questions about it:
“I asked the question to a building inspector… he had no idea. So he said, let’s just agree to disagree.”
Local Advice That Follows the Standards
At WA Building Inspections, we call it like it is. If it doesn’t meet NCC and AS requirements, we flag it. Whether you’re in:
…you can count on us for honest, independent building inspections.
We also offer:
FAQs About Weep Holes and Drainage
Where should weep holes be located?
Weep holes should be placed at the minus one course from the bottom of the brick wall, just above the flashing, not directly on the footing.
Are engineers wrong about weep hole placement?
Some engineers assume free-draining soil solves everything. But if the ground around the footing is hard or boxed in by paving, water has nowhere to go. Context matters.
What happens if weep holes are placed too low?
Water can build up around the base of the wall, leading to trapped moisture, mould, or even internal water ingress over time.
Do NCC and Australian Standards specify weep hole height?
Yes. Both AS3700 and AS4773 outline proper weep hole positioning as part of deemed-to-satisfy provisions in the NCC.
My Final Thoughts
“Weep holes must be at the minus one course. It makes no logical sense otherwise.”
As I always say, it’s not about winning arguments. It’s about getting the job done right.
“I’m itching to see how this is taken. We’ll see in the comments.”
If you’re not sure your build is up to code, get it inspected.
— Russell McCarthy
Founder & Lead Building Inspector
WA Building Inspections Perth
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