Australia’s Most Compact Fire Rated Boundary Wall Solution for Class 1 and 10A Timber Frame Buildings
Timber Frame
Separation
Insulation
Timber Frame
Building Type
The Hardie Smart Boundary Wall System is a fire and acoustic rated boundary wall solution for Class 1 and 10A timber frame boundary wall applications — a compact boundary wall solution up to 45% more compact than a 230mm thick brick veneer wall. For every 10 lineal metres, builders gain 1.25m² of floor space — a significant saving in usable land area while maximising property value across every development.
Under NCC Vol 2 Section 3.7.1, external walls in close proximity to the boundary must achieve a certified fire resistance level. The system uses a 90mm timber frame with 90x45mm timber studs, HardieFire 60mm insulation (insulation R-value 1.7, mineral wool density 80 kg/m³), 6mm external cladding, James Hardie internal lining, and HardieWrap weather barrier — delivering a fire rated boundary wall at just 102mm minimum wall thickness. No Gap Insulation is an authorised Australian supplier of HardieFire insulation for this system.
| Fire Resistance Level | FRL 60/60/60 (from the outside) |
| Acoustic Rating | Rw 47–48 |
| Total R-value | 1.59 to 1.93 m²k/W |
| Minimum Wall Thickness | 102mm |
| Frame Type | 90mm timber frame — 90x45mm studs |
| Insulation | HardieFire™ 60mm — R-value 1.7 |
| Insulation Density | 80 kg/m³ |
| External Face | 6mm James Hardie™ fibre cement |
| Weather Barrier | HardieWrap™ Weather Barrier |
| Service Cavity | 30mm |
| Stud Spacing | 600mm maximum |
| Nogging Spacing | 1200mm maximum |
| Bushfire Rating | Suitable up to BAL-FZ |
| Bracing Capacity | 4 to 10 kN/m (ULS) |
| Certification | CodeMark Certificate CM20135 |
Assessed FRL from the outside by CSIRO fire assessment and BRANZ assessment per AS 1530.4. CodeMark certificate CM20135 accepted by certifiers as a NCC compliance wall without additional sign-off in most standard applications.
At 102mm minimum wall thickness — 45% more compact than a 230mm thick brick veneer wall. For every 10 lineal metres, builders gain 1.25m² of floor space — a significant saving in usable land area while maximising property value.
Suitable for bushfire zone areas up to BAL-FZ — including flame zone and bushfire prone area wall applications — delivering certified facade fire compliance without the bulk of masonry alternatives.
Achieves a Rw rating of Rw 47–48 — providing meaningful sound attenuation for residential boundary wall and allotment boundary applications requiring dual fire and acoustic performance.
Certified total R-value of 1.59 to 1.93 m²k/W — assessed per AS/NZS 4859.2:2018 accounting for thermal bridging. Suitable for energy efficiency assessment under NCC 2019 Part 3.12.
The 30mm service cavity allows electrical cables in service cavity, plumbing pipes service cavity, and 20mm plumbing pipe service cavity without compromising the fire resistance level. Bostik FireBan One required at all penetrations to maintain the 60 minute fire rating.
The 6mm fibre cement sheet used as 6mm external cladding in this system is a genuine James Hardie fibre cement product — engineered to deliver a unique combination of performance properties that no other cladding material can match.
Working on townhouses terraces and detached buildings requiring NCC compliant boundary walls
Specifying a fire rated boundary wall for class 1 building boundary wall and class 10a building boundary wall applications
CodeMark certificate CM20135 and test reports available from James Hardie Engineering Solutions on 13 11 03
Requiring a compact boundary wall solution to maximise 1.25m² of floor space gains per 10 lineal metres
Requiring a bushfire prone area wall rated up to BAL-FZ
Developers requiring a zero lot boundary wall on tight urban lots
Required under NCC Vol 2 Section 3.7.1 for buildings within 900mm of boundary and walls on the allotment boundary. Boundary setback 500mm minimum applies in many councils. All design must comply with the National Construction Code.
Junctions and Connections Slab detail boundary wall and base detail slab require damp proof course and corrosion resistant metal flashing. Roof junction boundary wall requires fire resisting mineral wool to maintain FRL. Window detail fire rated wall requires appropriate flashing. Continuous sacrificial timber block (char blocking) must be sacrificial timber 45mm minimum.
Minimum Class 3 fastener required in standard applications. Class 4 fastener coastal mandatory within 1km of salt spray environment locations. All corrosion resistant fastener selections must follow fastener type limitation guidelines.
Component substitution is not permitted — HardieWrap weather barrier, HardieFire insulation, and 6mm external cladding must be used as specified. Full James Hardie warranty applies only when genuine James Hardie external cladding is used throughout.
