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Saving the OSPIRG building wasn’t going to be easy.

鈥淭he thing about (unreinforced masonry buildings) is the quality of the building is based on the quality of the mortar, and this building had terrible quality mortar,鈥� said Wade Younie, a structural engineer at DCI Engineers. 鈥淎ctually, you could rake your finger through it and it was like dust.鈥�

This year, the building that holds the offices of the Oregon State Public Interest Research Group, a Portland-based consumer advocacy group, is turning 100. Like many unreinforced masonry structures, the OSPIRG building 鈥� at 1536 Southeast 11th Ave. 鈥� lacked seismic strength. But after accommodating a hodgepodge of users (including a mortuary, a medical-related college and a photography studio), the tired structure needed more than an average stent.

Now, DCI Engineering, general contractor B&G Builders and Stack Architecture are in the final days of a creative project to give the building a new foundation 鈥� literally.

The project’s budget is $700,000; Gant Enderle, project manager for B&G, said the team originally hoped to spend only $500,000. But they continued to find problems that had to be addressed.

鈥淚t’s always fun to reuse an existing structure,鈥� Enderle said. 鈥淭his one had a lot of challenges because it was an old URM building sitting on an unreinforced concrete foundation and had really taken a beating over the years from the weather and whatnot.鈥�

The first step was to pour footings in the basement for new shear walls 鈥� two wooden walls running through the building’s central portion, and three 30-foot, reinforced walls running to the rooftop.

Because unreinforced masonry buildings have no rebar within their walls, Younie said part of the seismic upgrade involved spraying shotcrete on those masonry walls.

鈥淏ut the shotcrete guy said it would just blow the wall out,鈥� he said of the deteriorating mortar.

So, crews first had to go through the building with brushes, scrape out the old mortar and add it anew.

Another strategy involved installation of approximately 300 anchors to tie the masonry walls to the roof and floors. The problem there, Younie said, is that the city wasn’t convinced the anchors wouldn’t just rip away.

The team had to set up an on-site testing program for the anchors, ripping into walls while OSPIRG operated in its offices. Holes were drilled, epoxy was applied and anchors were set to determine the force needed to rip them free.

Younie has consulted on hundreds of seismic retrofits for URMs in Portland, including the Bridgeport brewpub building, the Trinity Place Apartments in Northwest Portland, and the former Globe Hotel (now the Oregon College of Oriental Medicine) in Old Town Chinatown. He said testing the quality of a building’s bones is critical for a successful seismic retrofit.

鈥淚 learn this lesson every time I do one of these old buildings: You really need to probe and dig into the existing materials, and in this case masonry, to figure out the quality and the actual construction,鈥� Younie said. 鈥淵ou have to do a little bit of selective demo to avoid surprises.鈥�

Convincing owners to take that step can be a challenge, he said.

Enderle said the project’s seismic portion is nearly complete, and crews are wrapping up work with the new mechanical system. Drywall work is next. Enderle is planning for the challenging, but rewarding project to wrap up in the first week of March.

鈥淲e’re at the point where every wall has been touched, and everything has been changed in some way, shape or form, and it will be a really nice place for them,鈥� he said.

Dave Rosenfeld, OSPIRG’s executive director, said the group purchased the building in 1990 to gain better control over long-term overhead costs; ultimately, the decision to renovate was fueled by the same desire. But it wasn’t made easily.

鈥淭his was not going to be cheap,鈥� he said. 鈥淥ver the long run it was cheaper than other options, but you’re still spending money up front and you want to do it right, and a seismic upgrade and remodel involves technical work that most of us don’t understand. And it’s scary to spend money on things you don’t understand.鈥�

Rosenfeld said he received assistance early in the process from a colleague who had helped her church navigate a similar one. He said he would someday like to assemble a white paper to help others tackle seismic retrofits. Until then, he said he’s open to sharing lessons learned.

鈥淎ny medium-sized business (is) welcome to give me a ring if they want to get some advice about how we did it,鈥� he said.