Designing BAAHOUSES for bushfire rated properties
Mount Tamborine site consultation & evaluation
Designing homes in bushfire-prone areas requires a thoughtful approach to ensure safety, compliance, and sustainability. At BAAHOUSE, we specialise in creating homes tailored for hinterland regions within bushfire-rated zones. Our designs prioritise the use of appropriate materials and construction techniques to meet stringent bushfire standards. Here, we share some insights into our design process, project case studies, and the suppliers we collaborate with to achieve bushfire resilience.
Understanding Bushfire Ratings
Bushfire Attack Level (BAL) ratings classify the potential risk of bushfire exposure for properties. The BAL rating of a property influences the design and construction requirements, dictating the materials and methods used to enhance bushfire resistance. Ratings range from BAL-LOW to BAL-FZ (Flame Zone), with each level imposing specific standards.
Key Design Considerations
Site assessment and planning
Conducting a thorough bushfire assessment is the first step. This includes evaluating the site's vegetation, slope, and proximity to potential fire hazards. Prior to your site consultation we check council overlays for your property to determine if your property is within a bushfire zone, and the affected area of the site. If your site is impacted, we send a site and floor plan early in the design process to our bushfire consultants for a bushfire report which will determine the design and materials we specify for your project.
Material selection
Utilising fire-resistant materials such as non-combustible cladding, rammed earth, fire resilient hardwood timber, metal roofing, and bushfire-rated windows and doors.
Incorporating ember guards, screens and bushfire shutters to prevent ember attack.
Bushfire resilient design principles
Consider the placement and orientation of the dwelling on the site.
Site buildings away from surrounding vegetation or neighbouring buildings when possible.
Site building in locations with low wind exposure to reduce the risk of embers.
Consider having your carport further away from the house as vehicles can burn for a long time.
Implementing construction methods that reduce gaps and openings where embers could penetrate the building envelope.
Consider building on a concrete slab on ground to remove the risk of flames reaching subfloor elements.
Roof designs should be simple with no valleys and minimal ridges to reduce the risk of collecting debris which embers can ignite.
Out buildings such as carports or sheds have to be built to the same level of protection as the house.
Ensure the design provides safe egress of occupants from the dwelling.
Bushfire resilient landscaping and maintenance
Designing the surrounding landscape to maintain clear zones around the building to reduce the risk of tree strike.
Some tree species can be used strategically as screening plants to function as a barrier against radiant heat exposure and to filter embers. These species include Lilly Pilly, Bottlebrush, Grevillea, Tea Trees, Banksia, and Sheoak.
Avoid planting shrubs near the dwelling densely, make sure there are breaks in the landscaping and use non-combustible mulch in garden beds.
Ensuring proper maintenance of the property to reduce fuel loads such as overhanging tree debris and combustible ground cover.
Project case studies
Case Study 1: Sandy Creek
Located in a BAL29 zone (high risk), with part of the shed located in a BAL40 (very high risk) zone, this project features:
Options of a steel-framed structure or 90x35mm KD HW timber studs using bush fire resistant timbers such as Merbau, Blackbutt, Spotted Gum, Red Ironbark and Silvertop Ash
Fibre cement cladding 9mm thick for the carport for BAL40, other areas 7.5mm thick for BAL29.
Bushfire-rated windows and doors with external metal mesh installed to all openable windows.
A metal roof with ember guards for the gutter and fire-resistant insulation.
Aluminium batten screening.
Aluminium windows and doors.
Case Study 2: Laceys Creek
Located in a BAL-29 (high risk) area, this project features:
Masonry Block wall.
Steel cladding wall.
Fibre cement cladding or option of Shou Sugi Ban (charred timber cladding)
Aluminium windows and doors.
Case Study 3: Whitsundays
Located in a BAL-FZ (high risk) area, this project features:
Steel roofing
Fire-rated external shutters on exterior windows
Fibre cement cladding 12mm thick to meet BALFAZ
Using sarking, or blaket and foil. gaps must be sealed at the fascia or wall line, hips and ridges by suitable mesh, mineral wool and/or other non-combustible materia
Aluminium battening
BALFZ windows and doors
Exterior natural stone or porcelain tile as opposed to timber decking
Collaborating with Trusted Suppliers
To ensure our homes meet the highest bushfire safety standards, we specify reputable suppliers who provide certified bushfire-resistant materials. These include:
Roofing
o Lysaght Roofing, Guttering & Fascia | Lysaght.com
o Bondor Roofing Archives - Bondor
Windows, doors & exterior shutters
o Bradnams Bushfire Rated Windows and Doors | Bradnam's Windows & Doors (bradnams.com.au)
o Paarhammer windows and doors Safety for all Bushfire Attack Levels BAL's (paarhammer.com.au)
o heroal.de/en/bushfire-shutters/index.php
Cladding and external walling
o Fibre Cement - Innova™ (innovafibrecement.com.au)
o Montage Fibre Cement https://bgcinnovadesign.com.au/facades- linings/innova/montage/
o Cladding: K-Clad fire resistant building products. FireCrunch Australasia
o Firecrunch FireCrunch: Fire Resistant Environmentally Friendly Building Boards
o External Fibre Cement Panels & Cladding Solutions | James Hardie (Axon, Stria, Linea, Hardieflex ranges)
o Sugi ban Shou Sugi Ban | Japanese Charred Timber Cladding (mortlock.com.au)
Rammed Earth
Decking
o K-Deck - FireCrunch Australasia
o BAL 29 Decking (Bush Fire Attack Level) - Futurewood
o Hardie™ Deck - Range of Premium Fibre Cement Decks | James Hardie
Aluminium Battening and slats
o Battens Product Information - Knotwood
o Slat Product Information - Knotwood
Masonry (suitable products include full masonry, brick veneer, mud brick, concrete, aerated concrete)
Your Partner in Bushfire-Resilient Design
If your property is within a bushfire-rated zone, BAAHOUSE can assist with obtaining the necessary materials and approvals to ensure your home is both beautiful and resilient. Our expertise in bushfire-safe design and construction means you can have peace of mind, knowing your home is built to withstand the challenges of living in a bushfire-prone area.
For more information on designing your bushfire-rated BAAHOUSE, contact us today.
