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.

Douglas-fir Association members are available to discuss solutions for all of your building requirements whether that involves treated or untreated Douglas-fir timber. Our members can advise you on all requirements regarding the use of Douglas-fir for both internal and external framing. Advice and solutions from our members includes functionality and design considerations and options using untreated Douglas-fir timber to minimise the use of treated timber in your home.

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 are available from Douglas-Fir Association members see http://www.douglasfir.co.nz/net/aboutus/who-we-are-aspx for contact details.

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

Let our members help you make the best choices for your home and for the environment.