Fire-Rated Exterior Painting Case Study: Garage Doors and Timber in Sydney
Fire protection doesn't have to make a home look industrial.
That was one of the key considerations on this residential painting project in Elanora Heights, on Sydney's Northern Beaches. Selected exterior areas needed a specialised fire-resistant coating system, but visually, the homeowner still wanted the property to look like one complete, well-designed home.
The scope included the exterior garage doors, timber around the entrance, the entrance ceiling and associated timber elements. The solution involved careful surface preparation, application of a specialist fire retardant painting system using FIRECOAT Exterior, followed by multiple coats of compatible white water-based exterior paint.
The result was quite different from simply "painting something with fire-rated paint". There were really two objectives.
First, the FIRECOAT system had to be applied correctly and at the required coating thickness. Second, the finished surfaces had to look clean, white and consistent with the existing architecture.
The original project specification called for two coats of FIRECOAT Exterior followed by exterior topcoats. FIRECOAT's current technical data describes the product as a water-based intumescent coating tested to AS 1530.8.1 for BAL-40, with a BAL-40 system requiring a minimum dry film thickness of approximately 0.7 mm.
Project at a Glance
- Location: Elanora Heights, NSW
- Project type: Residential exterior fire-resistant painting
- Areas treated: Garage doors, entrance timber ceiling, exterior timber elements and pillars
- Fire-resistant coating: FIRECOAT Exterior
- Fire coating application: Two full coats to the specified BAL-40 coating build
- Finish: White exterior water-based acrylic paint
- Finish coats: Approximately 3 to 4 coats where required for complete hiding and uniformity
- Application: Brush and roller
- Quality control: Coating application checked and documented by a licensed painter
The Challenge: Fire Protection Without Changing the House Design
A specialist coating often solves one problem and creates another.
FIRECOAT Exterior naturally has a slightly textured grey appearance. The manufacturer allows it to be left as the finish or covered with a compatible water-based exterior topcoat.
Grey, however, wasn't the look required for this home.
The rest of the property's exterior uses a light, predominantly white colour scheme. Leaving the garage doors and entrance timbers grey would have made the fire-treated sections visually obvious.
So the job wasn't finished once the fire-resistant coating had been applied.
We also needed to turn a relatively heavy grey undercoat system into a smooth-looking white finish that felt like it had always been part of the house.
This is something homeowners sometimes don't expect when discussing fire-rated paint. The technical coating and the decorative finish have different jobs.
The FIRECOAT layer provides the tested fire-resistant coating system. The exterior acrylic topcoats provide the colour, weather-facing finish and visual integration with the rest of the property.
Preparation Came First
One of the biggest issues discovered before coating was the condition of the existing paint.
There were areas of peeling and poor adhesion. Simply applying FIRECOAT over those sections would have meant relying on an unstable coating underneath the new system.
That wasn't acceptable.
The project specification therefore required loose, flaking and poorly adhered paint to be scraped away. Where necessary, coating removal continued until a sound substrate was reached. Remaining edges were feathered and sanded to avoid obvious transitions between previously painted sections and exposed surfaces.
This approach also follows the FIRECOAT Exterior technical guidance, which requires surfaces to be clean, dry and free from oil, grease, loose paint and other contaminants. Existing coatings with poor adhesion should be removed before application.
It's one of those stages customers rarely get excited about because much of the work disappears under the finished paint.
But in our experience, this is where a professional painting job is often won or lost.
A premium coating doesn't fix a failing substrate.
Repairing and Preparing the Exterior Timber
Once loose coatings had been removed, the timber and other painted surfaces were checked for imperfections.
Minor defects were repaired using suitable exterior-grade materials. Repaired sections were allowed to cure, sanded back and cleaned before coating.
Particular care was taken around edges, corners, joints and detailed timber sections. These areas can be harder to coat evenly, especially when applying a substantially heavier film than conventional decorative paint.
The objective was to create a stable, clean surface before any FIRECOAT was opened.
The prepared surfaces were then inspected before moving into the fire-resistant coating stage, as required by the project methodology.
Applying the FIRECOAT Exterior Undercoat System
FIRECOAT Exterior isn't simply a thick conventional primer.
It is an intumescent fire-resistant coating. When subjected to significant heat, intumescent technology is designed to expand and create a protective char layer that helps insulate the underlying substrate. Research behind FIRECOAT was developed through a collaboration between UNSW Sydney and Flame Security International.
For this project, two full FIRECOAT Exterior coats formed the fire-resistant base system.
For its BAL-40 specification, the manufacturer currently specifies approximately:
- 2 coats of FIRECOAT Exterior
- 1.43 m² per litre coverage per coat
- Approximately 1.4 mm combined wet film thickness
- Minimum finished dry film thickness of approximately 0.7 mm
Allowing the Fire Coating to Dry Properly
Heavy intumescent coatings need proper drying time.
FIRECOAT's current technical guide states that under ideal conditions, approximately 4 to 6 hours should be allowed between FIRECOAT Exterior coats, with at least 12 hours before applying a topcoat. Actual drying time can increase depending on temperature, humidity, air movement, film thickness and application method.
Rushing this stage can create unnecessary problems later.
The white finish couldn't simply be put over FIRECOAT because the surface looked dry from a distance. The coating needed sufficient time before the decorative system was introduced.
Turning the Grey FIRECOAT Finish White
This was probably the most noticeable transformation during the job.
Once the FIRECOAT system had dried, we moved from the technical fire-protection stage to the decorative exterior painting stage.
FIRECOAT Exterior is compatible with most suitable water-based exterior topcoats, although the manufacturer recommends testing the selected finish on a small area first. Water-based acrylic paint can be used over FIRECOAT for aesthetic purposes.
The selected finish for this property was white.
Initially, you might assume two coats of white exterior paint would be enough. In practice, the grey FIRECOAT base remained visible through the early finish coats in some areas.
Rather than leaving an uneven or slightly grey-white appearance, additional coats were applied where required.
Some sections therefore received approximately three to four coats of exterior water-based paint to reach the required opacity and visual consistency.
It wasn't about adding more fire protection.
It was about achieving the right decorative result.
That distinction is important when discussing this type of work with homeowners. Extra decorative topcoats shouldn't be presented as increasing the BAL rating. The critical fire-resistant layer is the correctly applied FIRECOAT system underneath.
Why So Many White Finish Coats?
Ever tried painting white over a dark grey surface?
The first coat rarely looks finished.
The same principle applied here, although the FIRECOAT substrate also has a slightly textured character because of its intumescent formulation. The manufacturer's technical documentation specifically notes that FIRECOAT Exterior naturally produces a slightly textured finish.
Applying additional finish coats helped improve:
Colour opacity
Consistency
Finish quality
Design integration
Quality Control and Painter Sign-Off
The FIRECOAT application also required more documentation than an ordinary exterior repaint.
The project methodology included checking the condition of the substrate, number of FIRECOAT coats, coating coverage, film thickness where required, drying periods, coating consistency and areas requiring additional material.
A licensed painter was also responsible for completing the FIRECOAT Exterior Application Quality Control Form as part of the completion documentation.
This aligns with the manufacturer's technical guide, which recommends maintaining application records and provides specific quality-control tables for coating inspection, wet and dry film thickness, application method and site conditions.
For specialist coatings, documentation matters.
If you're comparing painters in Sydney for fire-resistant coating work, we'd recommend asking how the contractor plans to document coating thickness and application rather than simply asking how many coats they intend to apply.
The Finished Result
The finished house doesn't immediately look like a "fire coating project".
And that's exactly what we wanted.
The garage door areas and entrance timbers now have the specialist coating system underneath, while the visible exterior remains white and consistent with the overall house design.
From the street and entrance, the treated surfaces integrate naturally with the surrounding cladding, trim and architectural details.
For this project, good professional painting services meant balancing technical coating requirements with ordinary homeowner expectations.
The owner didn't want grey fire paint to become a design feature.
They wanted fire-resistant treatment where required, followed by a normal-looking exterior finish.
