Products
ProRafter
PROJECTS
Specialised Timber Fabrication has a diverse range of projects covering educational, civil, residential and other sectors. Get inspired by our designs and see how we make your ideas become reality.
ProRafter
Post & Beams
Portal Frame Systems
Specialised Timber Fabrication has a diverse range of projects covering educational, civil, residential and other sectors. Get inspired by our designs and see how we make your ideas become reality.
Economised Systems
Specialised Timber Fabrication has a diverse range of projects covering educational, civil, residential and other sectors. Get inspired by our designs and see how we make your ideas become reality.
Overview
Traditional portal frame systems in timber provide an economised system with a soft aesthetic. Consideration must be given to the connections as this can substantially increase costs. Exposed plates, weather plywood or steel are the most economical, where as hidden connection require more fabrication and wider members to accommodate plates.
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Portals can be designed and fabricated from solid sections like LVL and Glulam but also on larger spars at it is more efficient to adopt box beams with x-banded LVL or plywood webs, and EWP Top and Bolton chords.
STANDARD DIMENSIONS FOR AUSTRALIAN PRORAFTERS
Pitch
Rise per
m of run
Rafter length
per m of run
Typical AU use
15°
268 mm
1.035 m
Sheds, skillions, low-slope sheet roofs
22.5°
315 m
1.049 m
Around the low limit for many concrete tile profiles
22.5°
414 m
1.082 m
The most common modern AU residential pitch
30°
557 m
1.155 m
Hamptons and period homes, terracotta tile
35°
700 m
1.221 m
Federation and steeper character builds
45°
1000 mm
1.414 m
Steep gables, architectural features, slate
35°
700 m
1.221 m
Federation and steeper character builds
17.5°
315 mm
1.049 m
Around the low limit for many concrete tile profiles
22.5°
414 mm
1.082 m
The most common modern AU residential pitch
30°
577 mm
1.155 m
Hamptons and period homes, terracotta tile
35°
700 mm
1.221 m
Federation and steeper character builds
45°
1000 mm
1.414 m
Steep gables, architectural features, slate
17.5°
315 mm
1.049 m
Around the low limit for many concrete tile profiles
22.5°
414 mm
1.082 m
The most common modern AU residential pitch
30°
577 mm
1.155 m
Hamptons and period homes, terracotta tile
35°
700 mm
1.221 m
Federation and steeper character builds
45°
1000 mm
1.414 m
Steep gables, architectural features, slate
EXAMPLES
