Balustrade Spacing Calculator
Calculate baluster count and spacing to meet the NCC 125mm maximum gap rule.
Estimate only — not a substitute for a licensed tradesperson, a certified engineer, or sign-off from your local building surveyor. Verify against current standards and site conditions before ordering materials or starting work.
Result
- Balusters required
- 20
- Actual gap achieved
- 115.79mm
NCC Housing Provisions clause 11.3.4(4) (verified 2026-08-20 on ncc.abcb.gov.au): openings in barriers must not permit a 125mm sphere to pass through. NCC 2022 remains the legally operative edition in most states/territories until each jurisdiction adopts NCC 2025 on its own timeline (e.g. NSW and QLD both 1 May 2027) - confirm which edition currently applies where you're building, and check for any state-specific variation, before relying on this.