New roofs

On new work, the roof is installed to the engineer’s and builder’s specification. Profile, pitch, fixing pattern and flashing details are usually set before work begins.

Bushfire-prone land

Much of the Shoalhaven is mapped as bushfire prone. Where a Bushfire Attack Level applies under AS 3959, the standard sets requirements for roof construction, including sealing gaps at ridges and eaves against ember entry.

Steel roof sheeting is non-combustible, one reason it is common on bushfire-prone land. The BAL rating for a property is set through the planning process.

Wind and fixing

Coastal sites often carry higher wind loads than sheltered inland ones. How many screws go into each sheet, and where, follows the manufacturer’s specification for the site’s wind classification.