fire zone

SERVICES

Trinity Design & Construction

New Homes, Extensions, Renovations & Improvements

making

TIME

to create

SPACE

for things that

MATTER

fire zone

SERVICES

Constructing a new home in an area with a designated Bushfire Attack Level (BAL)

Clients frequently inquire about bushfire attack levels and zones, and their impact on construction. Here we’ll outline the essential information to consider when building in a bushfire-rated area, including how it may influence the approval process, construction timeline, and budget.

What exactly is a Bushfire Attack Level (BAL)?

A Bushfire Attack Level (BAL) gauges the extent to which a building might be exposed to ember attacks, radiant heat, and direct flame contact. This assessment is typically measured in terms of radiant heat, expressed in kilowatts per square metre.

BAL ratings determine specific construction requirements and take into account factors such as your location, the proximity of vegetation to your property, and the site’s slope.

According to the Australian standard AS3959, which governs the construction of buildings in bushfire-prone areas, there are six main categories of bushfire attack levels. The categories are illustrated in the graphic below (examples included).

How does BAL impact my construction?

There are various standards you must adhere to depending on your site’s identified BAL rating. This will determine factors like home design, construction methods, and the materials used (among other considerations). Unfortunately, some of these factors can also impact the overall cost of your build.

These factors include, but are not limited to:

External Walls
For BAL ratings of 19 and above, external walls are required to be constructed from specific materials, such as non-combustible materials or bushfire-resistant timber. For construction projects located in a BAL-FZ zone (the highest possible rating), we recommend using products like James Hardie Axon fibre cement cladding due to its excellent fire resistance and durability.

Roofing
For a BAL 40 rating, roofing materials must be non-combustible, such as steel. In areas with a BAL rating of 12.5 and higher, roofs must be fully sarked, and the junction between the roof and walls must be thoroughly sealed.

Roof or Wall Penetrations
With a higher BAL rating, it’s important to consider any penetrations through walls or the roof. This applies to features like vents, extractor fans, and downpipes, all of which should be constructed from metal instead of PVC to provide greater resistance to heat.

Windows, Shutters, and Doors
Glass openings, such as windows and glass doors, are vulnerable to damage during a bushfire due to flying debris and intense heat. To mitigate this, it’s essential to use thicker, toughened glass paired with frames made from materials that meet the specific requirements of the BAL rating. Additionally, installing tight-fitting window shutters can offer extra protection during bushfires.

Decks and Subfloors
Floors should be constructed close to the ground, with a subfloor framework made from non-combustible materials. Depending on the BAL rating, decks should either be built from non-combustible materials or bushfire-resistant timber.
To reduce fire risk, decks are designed as separate, freestanding structures rather than being attached directly to the house. This way, if they catch fire, they can burn away from the house, preventing the fire from spreading to the main structure.

Sealing Gaps
It’s essential to seal any gaps between cladding and eaves, as well as around doors and windows, to stop embers from entering and potentially igniting the building. Additionally, sealing these gaps improves energy efficiency by reducing uncontrolled airflow and preventing heat loss.

Rainwater Tank for Firefighting

In bushfire-prone regions, local fire authorities may require the installation of a dedicated water tank on-site to provide firefighters with access to water for defending homes during emergencies. These firefighting water tanks must be above ground, constructed from non-combustible materials, and equipped with a pump system designed for firefighting purposes.

Additional Resources
For more information on building in a BAL-rated area, you can explore the following online resources:

NSW Rural Fire Service – Building in a Bush Fire Area

Bushfire Prone FAQs

How Can Trinity Design & Construction Help?
Trinity Design and Construction specializes in designing and building homes within various Bushfire Attack Levels (BAL), including (list BAL levels Trinity covers here). Our services include:

Approvals and Planning: We work closely with local government and private certifiers to ensure your project follows the correct approval pathway based on your specific BAL rating.
Expert Design: Our skilled designers ensure that your home design meets or exceeds all current BAL codes and standards.
High-Quality Construction: We use construction methods that not only comply with but often exceed the latest BAL requirements.
Trusted Suppliers: We collaborate with suppliers whose products are certified to meet or exceed BAL regulations.
Client Collaboration: We partner with you to identify your BAL rating and ensure your home meets all standards, prioritizing both safety and structural integrity while keeping your budget in mind.

Building with Trinity

Trinity Design and Construct is a versatile construction company specializing in building new homes, home extensions and additions, and home renovations. Our team of skilled professionals is dedicated to creating functional, beautiful living spaces that cater to individual needs and preferences. We also specialize in outdoor living improvements, such as decking, pergolas, and entertainment areas, as well as retaining walls for gardens. With a focus on quality craftsmanship and customer satisfaction, Trinity Design and Construct is your go-to partner for all your construction needs.

Contact Us

trinity

SERVICES

OUR

SPECIALITY

your

SPACES

Why Choose Trinity Design & Construction

Reliable Service

Affordable Pricing

customer service

local business

quality product

Why People Recommend Trinity Design & Construction

Ngaire Buckley

27 07 2025

We’ve had a great experience working with Josh and the team at Trinity. They have impressive communications, process and quality in their work. We have a beautiful deck thanks to them, and are already moving on to the next project. I recommend them to anyone for a building project.

Les Gray

09 10 2024

Excellent service, professional job & workmanship, always on time. Quoting process captured all our requirements & were remembered during the job as needed. The team’s professional & respectful approach was much appreciated. They ensured that they cleaned up at the end of each day. They communicated fully all the way through the project. Highly recommend this company.

Sue Huehn

31 05 2024

Joshua, Dylan and the team are wonderful builders. They fixed my driveway issues,, including replacing a retaining wall. Trinity created a beautiful deck with a privacy wall incorporating my rubbish bins. Internally, they fixed my window problems. Thanks guys !! I am very happy.

Melike Temel

16 09 2023

The best company I have ever dealt with. I can’t recommend these boys enough. 100/10 Always on time and their work is amazing. Thank you for everything you have done.

Paul Jay

28 08 2023

We had a custom designed wooden deck built and moulded to the shape of the pool. The results was amazing, Trinity Design and Construction were very professional and very plesant to work with.

Kimbo Davo

30 06 2023

Trinity Design & Construction built our backyard retaining wall and also our large decking area. They are highly professional, on time, polite, informative and their workmanship was outstanding. Highly recommend.

Peacock Family

13 05 2023

We found the team at Trinity Design & Construct to be really easy to work with. Their attention to detail was second to none and we wouldn't hesitate to recommend them.

Lachie Pembroke

13 05 2023

Trinity Design & Construct came out to repair a leaking window that required a strip down of one side of the house, they were on time, courteous, and left the site clean and tidy, most importantly; the repair worked! Thanks to Josh and the team for all your hard work, we will definitely be using their services again.

Adan Creative Designs

19 02 2023

We employed Trinity D&C to undertake many differing construction items in the build of our new home. Each task was undertaken with the quality, expertise, & efficiency that we were looking for. As I was also the Building Designer of the project, I was particularly impressed with the level of interest they took in the aesthetic detail that was required, & then the formulating of the construction methodology. Many a tradesperson would have simply looked for the simplest & most expedient way of completing the job. I have nothing but praise for Trinity D&C, & am forever grateful for their efforts. Thank you. Dan Briffa (Home Owner & Designer)

service

LOCATIONS

Trinity Design & Construction

Trinity Design & Construct offers custom home building and renovations servicing the Penrith, Blue Mountains, Hawkesbury & Sydney region. We believe in innovation, sustainable practices and everlasting craftsmanship.