Portland Bulk Terminals

Western Wood Structures was awarded a contract in 1995 to design and construct a Heavy Timber building on the banks of the Willamette River at Terminal 5 on property owned by the Port of Portland. The clear-span building measured 160’ x 1475’ and is used to store potash, a salt-like fertilizer that is mined in Eastern Canada, railed to Portland, and stored until ready for export across the Pacific.

Potash is highly corrosive to metal which makes engineered wood the perfect choice of building components. The steel connections used in this building required a special three-step epoxy coating to protect it from exposure to the potash. A metal building for an application such as this would have been cost prohibitive.

Glulam Arches are spaced typically at 32’ centers to carry the main roof loads. Glulam purlins are spaced at 4’ centers between the Arches and the roof is sheathed with 1-1/8” T & G plywood. All city fire codes were satisfied due to the Type IV Heavy Timber design employed.

Each Arch was pinned at the concrete abutments and at the top as well. This allowed for much of the roof framing to be accomplished on the ground making erection much easier as the frames were lifted and pinned in pairs.


One end wall was panelized in sections in anticipation of future expansion. It was planned that this wall would some day be dismantled and re-used when the building was added on to.

In 2006 Western Wood was awarded the contract to design and construct the anticipated addition. This addition increased the length of the existing structure by 608’ resulting in a building that now measures 160’ x 2155’. The building is now the equivalent of six football fields in length. The floor area is now 344,800 s/f and to our knowledge this building is now the largest wood framed clear-span building in Oregon. By comparison, the Tillamook Air Museum which was originally built as a blimp hangar in the 1940’s, measures 296’ x 1072’ and has a floor area of 317,312 s/f. The Chiles Center dome at the University of Portland, also a WWS project, is the largest clear-span timber building in Oregon that we know of with a diameter of 305’.