Stability

Building with Douglas-fir

Douglas-fir is a superb timber for building. It offers real benefits because of its strength, stiffness, durability and decay resistance. This makes it particularly suitable for use in frames and trusses and because Douglas-fir does not have a low stiffness core it is able to deliver large section beams, joists and rafters in SG (stress graded) 8, 10 and better. There are opportunities to use Douglas-fir as an Untreated ‘Chemical-free’ choice because of its inherent properties. There are treated and non-treated options for use. See our product categories.

Douglas-fir offers strength, stability, stiffness and increased moisture and decay resistance. Find out more about these key Characteristics.

Acceptable and alternate solutions for the use of untreated Douglas-Fir in buildings with low to high risk matrix scores

Low Risk 0-6

Using acceptable solutions B2/AS1 for all external and internal framing and roof framing

Acceptable solution B2/AS1 2011 Para 3.2.2.2 all UTDF

Medium Risk 7-12

Acceptable solution B2/AS1 2011 Para 3.2.2.2
All framing H1.2

High Risk 13-20

Acceptable solution B2/AS1 2011 Para 3.2.2.2
All framing H1.2

NOTE 1: Alternative solutions for untreated Douglas-Fir for all internal framing and truss roof framing for medium and high risk buildings may be available see where to source douglas-fir for contact details.

  • Untreated Douglas-Fir
  • H1.2 Treated Douglas-Fir
  • H5 Treated