Learn more about using salvaged lumber in residential construction projects

In this article

A new development project underway in Northeast Portland offers insights into the City's first use of salvaged lumber in the structural designs of new residential buildings.

In 2017, the Oregon Residential Specialty Code was updated to allow local building officials to review the use of used materials and equipment in new construction, alterations and additions. Waste and recycling policy makers and advocates from the Portland metro region requested this update to provide a pathway to reuse valuable building materials, as long as the materials met the performance requirements of comparable new materials.

In the years since, Permitting & Development did not receive a permit application requesting to use salvaged lumber in a new structure, until recently. Sabin Community Development Corporation partnered with the Bureau of Planning and Sustainability's Commercial Deconstruction Program to deconstruct its Avenue Plaza apartment building at 5025 NE 8th Ave. A new highly efficient 78-unit building is under development to replace the former 22-unit apartment building. Sabin CDC requested to retain some of the salvaged lumber from the 1960s apartment building to use in a new Accessory Dwelling Unit (ADU) that will be built later in 2026, behind an existing single-dwelling house, also in NE Portland.

Learn more about this project

The City's Building Official affirmed that the residential building code allows the use of salvaged lumber, provided that material must be in good condition and clearly identified on the plans and clearly in the field.

What the building code allows

Under an exception in Oregon Residential Specialty Code R104.9.1, PP&D will allow non-grade-stamped salvaged lumber "in good condition" outright, without a Building Code Appeal, provided the structural design treats the salvage lumber as no better than DF-L #2.

For residential projects (one- and two-family homes), ungraded salvaged lumber may be used for construction, without an appeal, as long as salvaged lumber is in "generally good condition" and "free of any obvious areas of decay." This means:

• No signs of structural cracking, splitting, or delamination
• Holes are limited and not clustered or oversized
• Moisture exposure was brief and wood is fully dry with no decay or rot (soft, crumbly, or spongy fibers)
• No evidence of mold, rot, or insect activity (tunnels or powder)
• No deep cracks, splits, warping or crushed fibers
• No evidence of long-term moisture exposure with staining, swelling or decay
• No severe burn damage or charring

The salvaged lumber will be treated structurally as if it is Douglas Fir-Larch (DF-L) #2 (approx. 6%-9% less span than SS "old growth").

Salvaged lumber must be clearly labeled on plans and on site. On-site this can include a paint mark, using a consistent color of paint, through the center portion of the piece of lumber. Writing or stamping "SALVAGED" in indelible ink is another option.

How plans and materials will be evaluated

A structural plan reviewer will check loading on salvaged structural members and their max spans, assuming those members are Douglas Fir (DF-L) #2 grade.

After the building permit is issued and construction is underway, PP&D's residential inspectors will verify the salvaged structural lumber in the field is in good condition.

Other than salvaged lumber, a Building Code Appeal will still be required in most cases to reuse other building materials and building elements, such as reusing a window in a new wall.

Why use salvaged lumber?

Most homes built in Portland prior to the 1970s used framing lumber that came from either old growth forests or long-growth cycle forestry practices. When this lumber was first milled, it was up to twice as dense and strong as today's lumber, which typically comes from fast-growing forestry practices. While the lumber does lose some strength over time while installed in a structure, it is strong enough to meet or surpass the compressive strength of new lumber today. By using salvaged lumber in new structures, there is reduced demand to cut more trees for new material. It also preserves the history of our region within the walls of the new structure.

Where does salvaged lumber come from?

In 2016, Portland was the first city in the United States with a deconstruction ordinance, which now requires houses and duplexes built before 1941 to be manually deconstructed. Deconstruction is a best practice for discovering and managing hazardous materials in homes that are planned to be removed. It also reduces the amount of dust and debris that can escape to neighboring properties, as well as offer the best opportunity to salvaged materials for reuse while they are still in the most preserved and complete state. Each house deconstructed through this program produces about three to four tons of reusable salvaged lumber and other historic or practical elements such as windows, doors, and cabinets. This material is offered for sale at salvaged material retailers.

Learn more about the City of Portland's Deconstruction Program

For more information

If you are considering using salvaged lumber in your residential construction project and have additional questions, please schedule a free 15-minute appointment with a residential building code reviewer before submitting a permit application.