An Ounce of Prevention

Thanks to Grant Kirker for writing this article spotlighting how homeowner’s can better maintain their wood decks. Kirker is a Research Forest Products Technologist at FPL in the Durability and Wood Protection Research unit.

The experimental test block setup used to examine the role of accumulated leaf litter on material performance and wood durability in aboveground exposure. The test block is surrounded by untreated pine and the channel between the block and frame is filled with leaf litter. The two black fittings on the top are able to take repeated moisture measurement using a pin-type moisture probe. USDA Forest Service Forest Products Laboratory

Benjamin Franklin is credited with the saying “an ounce of prevention is worth a pound of cure”, which suggests that taking steps to avert a problem before it starts is far better than taking corrective steps after the problem arises. Forest Products Laboratory (FPL) Wood Durability and Protection researchers, in collaboration with research partners at Oregon State University, attempted to apply this concept to a situation close to home for many homeowners—the wooden deck.

The global wooden decking market in 2020 was valued at $15 billion USD, of which the North American markets made up about 35%, or $5.25 billion USD1. In a 2019 National Association of Homebuilders (NAHB) survey2, 20.3% of all new houses included decks. Although this estimate is lower than historical averages, the global pandemic has led to an increasing interest in outdoor living spaces, which will likely cause this market to increase. Wood is an excellent building material for outdoor decking because of its  reasonable cost and low maintenance requirements; if properly installed and maintained, a wood deck can provide a long-lasting benefit to the homeowner.

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Engineers from FPL and the VA Inspect 134-Year-Old Milwaukee Medical Center Building

The first building in what is now the Clement J. Zablocki Veterans Administration Medical Center (VAMC) in Milwaukee, Wisconsin, was originally approved for construction by President Abraham Lincoln just one month before the end of the Civil War, for the care of disabled soldiers. That structure was completed in 1869.

Originally called the National Home for Disabled Volunteer Soldiers and nicknamed the “Old Main,” the Zablocki VAMC now consists of 20 buildings.

Adam Senalik, FPL Engineer, visually inspecting the studs of a wall on the top floor of Building 7 at the Zablocki VAMC.

Last week, it was time for an inspection of Building 7 – the Soldiers’ Home. Like Buildings 2 and 5, it was built as a barracks for soldiers receiving care at the Milwaukee Soldiers Home. Consisting of three stories and a large basement foundation, the Soldier’s Home, designed by celebrated architect Henry Koch, was ready for business in 1888. Building 7 now supports the offices of the Compensated Work Therapy Department. New IT requirements require the VAMC to update the structural integrity of some of the older buildings.

Bob Ross, FPL Engineer, investigating the structural members in the wall system on the top floor of building 7. Note that the outer layers of the wall have been removed to expose the structural members.

To that end, Forest Products Laboratory Research General Engineers Bob Ross and Adam Senalik took the 90-minute drive to Milwaukee to join Erik Billstrom, on-site engineer for the VA, to carry out the necessary structural analyses.

Erik Billstrom, VA engineer, examines a large white pine timber in the high ceiling of the basement maintenance room and finds he is easily able to remove wood samples by hand.

According to Bob and Adam, FPL regularly receives requests for structural condition assessments, mostly dealing with historic wood structures, structural assessment, inspection, and assignment of allowable design values.

“We usually try to provide direct assistance to other Federal agencies and Departments,” said Bob. “This is especially true for the DoD and Veterans’ Administration.

“What matters most here,” added Bob, “is that this campus does good things for veterans.” The Zablocki VAMC serves more than 64,000 U.S. veterans every year.

Bob added that the book he coauthored, Wood and Timber Condition Assessment Manual, now in its second edition, summarizes structural condition assessment research currently used for wood and timber structures. The publication can be found at:  https://www.fpl.fs.fed.us/documnts/fplgtr/fpl_gtr234.pdf.  A previous FPL LabNotes article provides a summary of the manual here:  https://www.fpl.fs.fed.us/labnotes/?p=4599.

Bob Ross reveals a deteriorated nail from the basement ceiling

Starting on the third floor of building 7, the three engineers began to examine the condition of the walls and ceiling.

“It’s in pretty bad shape,” said Adam. “But about what we expected.” Previous engineering analyses had found that the structural beams were not designed for heavy weight. 

The group then climbed up into the dark attic above the third floor and removed a few samples of wood. The blackened strips of wood appeared as if they had been in a fire.

“Maybe they were at one time,” observed Bob. “Further analysis will tell us.”

Satisfied with their inspection and the samples they had acquired, the analysts moved down to the utility room on the basement level. Here, the late 19th-century origins of the building were even more apparent, with period arches and a brick wall that had survived more than a century of water damage. The wall appeared not unlike a medieval dungeon in its heavily “blurred” condition.

Erik set up and climbed a tall step ladder to examine a large white pine timber across the ceiling of the basement. He reached in and was able to effortlessly lift spacers out of the surrounding structure. Finally, the three engineers placed all their gathered samples into large, labeled plastic bags.

“It was a good inspection,” Adam concluded. “I only hope that this building can be saved.”

Reducing Wildfires through Better Utility Pole Inspections

They can pop up almost anywhere.

“They” are wildfires, which can result in loss of human life and lead to billions of dollars of property damage every year in the United States.

Hundreds of failures in electrical utility poles across the nation are one of the leading causes of these disasters. In Idaho alone, nearly 300 wildfires have been caused by utility pole failures in the past 15 years – an average of 20 wildfires every year.

Electrical utility pole failure is one of the leading causes of wildfires nationwide. The sheer number of poles involved makes regular inspections challenging – but the Forest Products Lab is finding new ways to carry out pole inspections quickly and easily. (Forest Service photo)
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FPL Researcher Featured in Engineering News-Record

A rendering of the 25-story Ascent building currently under construction in Milwaukee, Wisconsin. Photo credit: Korb + Associates
Laura Hasburgh
Building and Fire Sciences
Materials Research Engineer

Engineering News-Record recently featured Forest Products Laboratory’s (FPL) materials research engineer, Laura Hasburgh and her expert consultation on the Ascent construction project in Milwaukee. At 25 stories, the Ascent building is making history as the soon-to-be tallest timber building in the world. And because of its unprecedented height and exposed mass timber interior, Hasburgh was contacted to lend her fire testing expertise.

The top eighteen floors of the Ascent will be framed in mass timber and the interior architectural design features exposed glued-laminated timber (glulam) framing and cross-laminated timber (CLT) slabs to showcase the natural beauty of the wood. But with these design and material choices, the Ascent’s fire safety planning needed to be carefully considered.

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FPL Researcher Featured on National Public Radio

Brian Brashaw
Forest Products Marketing Unit
Program Manager

Forest Products Laboratory’s (FPL) Brian Brashaw was featured in an National Public Radio (NPR) segment about the soon-to-be world’s tallest timber building currently under construction in Milwaukee, Wisconsin. The Ascent building will boast 25 stories, 18 of which will be framed in mass timber. The upscale apartment complex is slated for completion in 2022. Right now, the cement foundation is being laid. Brashaw anticipates the Cross Laminated Timber (CLT) “to start flying,” or rather, construction crane hoisted pre-fabricated mass timber sections to begin installation in early summer 2021.  

FPL is excited about its participation in helping the Ascent rise among the tallest modern wood structures in the world.

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