Framing near you

Part H1 of NCC 2022 Volume Two is short because it delegates. H1D2 lets a Class 1 or Class 10 building follow Section 2 of the ABCB Housing Provisions, or the relevant provisions of H1D3 to H1D12, or a combination of the two. When the design goes down the standards route, H1D6(4) names them explicitly for timber: AS 1720.1 for the design of timber structures, AS 1720.5 for nailplated timber roof trusses, AS 1684.2 or AS 1684.4 for residential timber-framed construction in non-cyclonic areas, AS 1684.3 for cyclonic areas, and AS 1860.2 for the installation of particleboard flooring.

Steel framing has its own list in the same clause: the NASH Standard for residential and low-rise steel framing, AS 4100 for steel structures and AS/NZS 4600 for cold-formed steel structures. The Housing Provisions add their own framing content in Part 6, which covers the scope and application of the framing section, subfloor ventilation and structural steel members.

None of this is homework for the homeowner. It is a set of questions worth asking, because a builder who can tell you which of those documents the frame was designed under, and at what wind class, is describing a frame somebody engineered rather than a frame somebody remembered.

Structural timber is sold on graded strength, not appearance, and the grade is what the span tables in AS 1684 are written against. A quote that lists a member size with no grade has given you half the specification, because a stud of the same dimension can belong to quite different strength classes. The same applies to the seasoning: unseasoned hardwood and kiln-dried softwood shrink by different amounts as the frame dries out, which is why a frame that mixes them without thought ends up with doors that bind in the first summer.

The connection hardware deserves the same attention as the timber. Bracing only works if it is fixed with the fasteners the bracing system was tested with, and tie-down only works if every link in the chain is present. Substituting a cheaper strap or a shorter screw somewhere in that chain is invisible on site and decisive in a storm.

There is no national carpentry licence, so the answer depends on the state. Queensland is the most explicit: the QBCC carpentry trade licence covers constructing and erecting timber and steel wall framing and roof structures, along with non-loadbearing partitions, installing windows, doors, ceilings, subfloors, flooring, roofing and stairs, fixing internal linings, panelling and mouldings, restoring and renovating doors, windows and frames, and concreting to simple forms including formwork and reinforcement.

The same licence is explicit about what a carpenter may not touch. Plumbing and drainage, termite management and pest control, fire protection work, gasfitting and mechanical services are excluded, and the QBCC does not allow a carpenter to pick them up as incidental work regardless of value. That matters on a frame, because a chemical termite management system and a fire-protected penetration are both things that happen around framing but are not framing.

Elsewhere the structure of the rules differs rather than the substance. New South Wales licenses carpentry as its own contractor category above a value threshold, Victoria reserves major domestic building work for registered building practitioners, and South Australia and Western Australia each run their own building work contractor registration. Look the licence up on that state's register before the frame is ordered, not after it is standing.