Timber’s Time


    Thanks to a big change in the International Building Code, and a dramatic rise in building costs, concrete is losing market share to timber in the apartment construction industry — and the concrete industry is fighting back.

    The National Ready Mixed Concrete Association (NRMCA), through an affiliate named Build with Strength, has mounted a campaign called “America is Burning,” in which every fire that takes place at wood-framed multifamily complexes — more than 50 since 2013 — is documented. Recent multifamily fires in Oakland and in College Park, Md., drew swift criticism from the concrete industry. “Maryland Apartment Fires Renew Calls for Stronger Building Codes,” reads the College Park release. The subhead for the Oakland fire says, “Fire Highlights Vulnerabilities with Wood-Framing, Lax Building Codes.”

    Racing against the relentless pace of innovation, the building code, and a dramatic rise in the raw cost of concrete — from $26 per gross square foot to $36 per gross square foot in the bellwether Washington, D.C., market — the concrete industry is trying to tell the world it’s more cost effective, lasts longer, and, of course, that it’s more resistant to fire than its wood competitor.

    But is the message being heard?

    Though there is no guess as to when and if it will pass, in March the Timber Innovation Act was introduced in the U.S. Senate, and among the nearly 100 organizations supporting the bi-partisan bill are state forestry groups from California to New England, the National Wildlife Federation, and timber giant Weyerhaeuser. The bill’s introduction in Washington comes as timber “plyscrapers” are sprouting up across Europe, and as the era of U.S. plyscrapers begins in Oregon with the permitting of a 12-story structure in Portland.

    But for the NRMCA, the prime focus is not on wood towers but on the low- and mid-rise wood-framed apartment market, where a recent change in the building code brought about a profound change in the density multifamily wood construction can achieve. The change enabled what’s known as “five-over-two” and “five-over-three” construction, or five wood-framed levels separated by a concrete slab with two or three concrete-and-steel levels below (see Figure 1). What’s missing in all this? High-rise construction, the purview of concrete and steel.

    Figure 1: “Five-over-three” construction

    By some estimates, “five-over-two” can be as much as $70,000 per unit cheaper than high-rise, meaning builders are oftentimes opting for the more affordable option. The result? A dip in market share for concrete. And the numbers bear that out. Last year, according to the U.S. Census Bureau, of the 13,000 “multifamily buildings completed by framing,” 11,000 were in wood, 1,000 in steel, and the remaining 1,000 framed with concrete.

    But Kevin Lawlor, a spokesman for Build with Strength, a national coalition of architects, engineers, and fire officials directly affiliated with the NRMCA, is having none of the hype about wood.

    “We see a lot of it going up and a lot of it burning down,” he said.

    And Lawlor has a point.

    Based on the list maintained by the America is Burning campaign (http://buildwithstrength.com/america-is-burning), there have been more than 30 fires in low- and mid-rise wooden buildings across the country just this year. The May fire near Oakland was the second at the same location — a five-story wood-framed retail-apartment complex still under construction. The fire was huge, too, and nearly caused the collapse of a construction crane.

    Another massive fire broke out in April at an under-construction apartment complex in College Park, Md. According to local news accounts, it was the largest fire in the history of Prince George’s County, causing about $40 million in damage. The building employed “lightweight wood truss construction” in the upper floors, where the fire occurred, according to local accounts.

    Enough said, in Lawlor’s opinion. “We advocate for the use of non-combustible materials,” he said.

    Since 2013, more than 50 fires have destroyed wood-framed multifamily complexes, according to Build With Strength.

    In terms of price, Lawlor and his organization downplay the idea that building with wood is more cost-effective than building with concrete and steel, citing the key aspects of safety, efficiency, and durability.

    “From the way we see it, it’s that developers see [wood] as a cheap and quick way to build,” Lawlor said. “That’s a misconception people are buying into. We don’t concede the cost argument.”

    But Dick Knapp, senior vice president of acquisitions for Washington, D.C.-based development firm Foulger-Pratt, disagrees with Lawlor. And, Knapp said, the concrete industry is only lashing out at wood because wood has made a big move in the market.

    “They’re threatened by the arithmetic,” Knapp said. “They are responding to the competitiveness of stick.”

    Knapp, however, said there’s certainly a time and place for concrete — deep in the urban core where steep land prices dictate that only high-rise concrete-and-steel construction makes financial sense.

    “That’s where concrete shines,” Knapp said.

    As it pushes for more restrictive building codes, Build with Strength also monitors local, state, and federal legislation, and is currently opposing SB 5379 in the Washington State senate. The bill, which requires public buildings under 12 stories tall to be constructed with cross-laminated timber, is currently in committee. Build with Strength opposes the bill on 10 points, challenging timber’s key assertions that logging is sustainable and that timber buildings prevent global warming (see, “SB 5379 opposition”).

    Build with Strength also opposes the Timber Innovation Act. Lawlor said he doubts the bill will pass, and criticizes it for picking “winners and losers” by giving incentives to the wood industry for research and development.

    But timber appears unfazed by concrete’s opposition. Robert Glowinski, president and CEO of the American Wood Council, brushed off concrete’s criticism, saying, “What I think you’re seeing is the response of a competing industry. I’m not surprised by it.”

    Glowinski was quick to point out the obvious: “There’s opportunity for all kinds of construction in the market.”

    Glowinski is right. As the wood industry grows, concrete maintains its established place in the construction market at $40 billion annually.

    Still, a plug on the American Wood Council’s website makes it clear how high the stakes are.

    “With the global marketplace for green building materials estimated to reach $529 billion by 2020, securing a strong place for wood is essential to the wood products industry’s future growth. That means both telling the positive story of wood’s renewable, energy-efficient advantages, as well as defending against anti-wood bias in rating systems. Strong, unified industry support is essential as the green building battlefield continues to spread from the state to the federal level.”

    With nearly 40 years in the industry, Glowinski has seen just about everything. What’s come in recent years, however, has been transformative. Reductions in embedded energy — the energy it takes to produce a building — as well as air emissions and greenhouse gases have been considerable. Add to that mass timber — cross-laminated timber (CLT), nail-laminated timber, and glue-laminated timber — and wood has an appeal it didn’t have not too long ago.

    “The arc has been a progression,” Glowinski said, referring to the re-emergence of timber products.

    Mass timber — cross-laminated timber, nail-laminated timber, and glue-laminated timber —
    and wood has an appeal for multifamily low- and mid-rise construction. Photo: FPInnovations

    The proof of wood’s ascension isn’t hard to find, either. There’s the Candlewood Suites in Alabama, the first hotel in the U.S. made with CLT, and the recently permitted Framework building in Portland, which, at 12 stories, will be the nation’s tallest timber building when completed late next year (see “A framework for wood construction” on page 36). Currently, the tallest timber structure in the U.S. is the T3 office building in Minneapolis.

    Perhaps the arrival of a new era for timber is best stated by Justin Adams, global managing director for lands at none other than The Nature Conservancy, considered the gold standard for environmental protection. In February, he addressed the crowd at a GreenBiz conference in Phoenix.

    “What we have to do is start telling a business story of where the opportunities are to unlock the potential [of timber],” Adams said. “There’s a huge opportunity for us to start thinking about and reimagining how we build in the future and how we create a new age for timber.”


    [divider]Wood products industry at a glance[/divider]
    Wood products: 428,500 employees
    Forestry and logging: 135,600 employees
    Total: 564,100 employees
    Manufacturing facilities:
    Sawmills, millwork, treating: 625
    Engineered wood and panel: 176
    Other wood products: 101
    Total: 902
    Timberland (U.S. Forest Service, 2012; in thousands of acres)
    National Forest System: 98,308
    Other federal: 14,002
    State, county, and municipal: 48,668
    Private corp.: 111,279
    Private non-corp.: 248,896
    Total timberland: 521,154
    Source: American Wood Council
    [divider]SB 5379 opposition[/divider]
    Build with Strength offered the following rebuttals to 10 assertions in Washington State’s SB 5379 (Constructing New Public Buildings with Cross-Laminated Timber):
    1. Wood products help with carbon sequestration — Only 15 percent of CO2 stored in a tree is actually sequestered. The rest goes up into the atmosphere as logging/mill waste and processing emissions.
    2. Using timber prevents global warming — According to MIT, the operational-use phase of a building represents 88 percent to 98 percent of its global warming potential, dwarfing climate change impacts resulting from materials choice.
    3. Logging is environmentally friendly — Atrazine, a known endocrine disruptor and likely carcinogen, is common in U.S. logging practices.
    4. Logging is a sustainable business practice — Focusing on embodied carbon ignores the worst impacts of forest management — ecosystem depletion and biodiversity, as well as soil and water quality.
    5. Since we can replant trees, logging is okay — Clear cutting is “an ecological trauma that has no precedent in nature except for a major volcanic eruption.”
    6. New “wood technologies” are better for taller buildings — Wood burns and doesn’t withstand Mother Nature. It’s a building material that can’t hold up to Washington State’s need for resilient construction.
    7. Taller mass timber buildings are safer — Mass timber, including cross-laminated timber (CLT), is classified as a “combustible construction” material in the International Building Code.
    8. First responders support taller mass timber buildings — Heavy timber construction is one of the most dangerous types of construction facing firefighters and first responders. Research and experience shows CLT burns hotter and longer than even wood frame construction, putting occupants and firefighters at risk. Biased state legislation shouldn’t replace the ICC process.
    9. Taller mass timber buildings are code compliant — Fire and code officials do not have a quantitative method for assessing the level of fire safety of CLT buildings. This is why there is a newly created code committee to study this.
    10. This bill will create jobs — A study on the impact of mandating wood construction in Oregon found that a mere 38.1 jobs were created in two years.

    Source: Build with Strength


    [divider]Fire testing[/divider]Fire testing completed on full-scale mass timber buildingThe American Wood Council reported that five, full-scale mass timber fire tests in a multi-story apartment building were completed “with promising results.” The International Code Council Ad-hoc Committee on Tall Wood Buildings provided the five fire scenarios that were tested in each of the two, one-bedroom apartments constructed using mass timber. The test scenarios included various arrangements of exposed and unexposed cross-laminated timber (CLT) with open doors between living and sleeping areas. Additionally, automatic sprinkler systems effectiveness was evaluated.

    • Test 1 — A mass timber structure fully protected with gypsum wall board was subjected to a large furnishings and contents fire. The test was terminated after three hours without significant charring on the protected wood surfaces of the structure.
    • Test 2 — Approximately 30 percent of the CLT ceiling area in the living room and bedroom were left exposed. The test was terminated after four hours, providing additional time to determine if there would be any significant fire contribution from the exposed CLT. Notably, once the furnishings and contents had been consumed by the fire, the exposed CLT essentially self-extinguished due to the formation of char that protected the underlying wood.
    • Test 3 — Parallel CLT walls were left exposed, one in the living room and one in the bedroom. Similar to Test 2, once the apartment furnishings and contents had been consumed by the fire, during which a protective surface of char formed on the CLT, the mass timber surfaces essentially self-extinguished.
    • Tests 4 and 5 — Examined the effects of sprinkler protection. For both tests, all mass timber surfaces in the living room and bedroom were left exposed. Test 4 demonstrated that under normal operating conditions, a single sprinkler easily contained the fire. For Test 5, the fire was allowed to grow in the compartment for 23 minutes before water was supplied to the sprinklers, which quickly controlled the fire.

    “The results of these fire tests will continue to be studied and will help inform code change recommendations from the Ad-hoc Committee later this year,” said Stephen J. DiGiovanni, P.E., Ad-hoc Committee chair and fire protection engineer for the Clark County, Nev., Department of Building and Fire Protection. “These tests are an important part of the extensive research data the committee has reviewed to validate the performance of tall wood buildings.”

    The tests were funded in partnership with the U.S. Forest Service’s Forest Products Laboratory and the American Wood Council, and were conducted at the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives Fire Research Laboratory. A General Technical Report FPL-GTR-247 on the fire tests will be available from the Forest Products Laboratory (www.fpl.fs.fed.us) in the near future.


    Richard Massey is director of newsletters and special publications at Zweig Group and editor of The Zweig Letter. He can be reached at rmassey@zwieiggroup.com.