Maximum Allowable Gaps (100 mm Rule)
One of the most important measurements during every Pool Safety Inspection is 100 millimetres.
Queensland pool safety legislation limits the size of openings within a pool barrier because a young child must not be able to pass through or under the fence.
Although the rule sounds simple, it applies to many different parts of the pool barrier.
Where Does the 100mm Rule Apply?
During an inspection, we assess openings including:
- Gaps beneath the pool fence.
- Gaps between vertical fence members.
- Openings between fence panels.
- Gaps beside gates.
- Spaces created by fence movement.
- Openings between the pool fence and adjoining structures.
- Gaps where boundary fences form part of the barrier.
Every one of these measurements must comply.
Why 100mm?
The 100mm limit has been adopted because it helps prevent a small child from squeezing through an opening in the barrier.
Even if a gap appears only slightly larger than 100mm, it may no longer comply with Queensland legislation.
For this reason, inspectors measure critical openings carefully rather than estimating them by eye.
How Do Gaps Become Too Large?
Many non-compliant gaps develop over time due to:
- Fence movement.
- Soil erosion.
- Retaining wall movement.
- Timber shrinkage.
- Corrosion.
- Gate adjustment problems.
- Ageing structures.
- Storm damage.
A pool fence that complied when it was installed may no longer comply years later.
Common Examples
Some of the most common examples include:
- A fence panel lifting after ground movement.
- A gate that no longer lines up correctly.
- A timber fence shrinking and creating larger openings.
- A detached boundary fence creating an entry point.
- Soil washing away beneath the fence.
Most homeowners don’t notice these gradual changes until an inspection is carried out.
Can Small Defects Matter?
Absolutely.
Even a relatively small increase in an opening can prevent a Pool Safety Certificate from being issued.
The good news is that many of these defects can be repaired quickly once identified.
From the Inspector
The 100mm rule is probably the measurement I check most often during every inspection.
Homeowners are often surprised that a fence which appears perfectly secure can fail because of a gap that has slowly increased over many years.
Regular maintenance and early repairs usually prevent these small issues from becoming larger and more expensive problems.
Related Articles
- Ground Levels Around Pool Fences
- Common Pool Safety Compliance Issues
- Fence Movement and Structural Integrity
- Boundary Fences Used as Pool Barriers
Contact Pool Compliance Gold Coast
If you’re unsure whether your pool barrier complies with the 100mm rule, contact Pool Compliance Gold Coast for a professional Pool Safety Inspection.
