Why timber towers are a solid plan for building NYC


They’re shouting “timber,” but nothing is falling. In fact, wood is on the rise.

Architects and developers across the globe are racing to build a new breed of structures created not from the cast iron, masonry or steel of yesteryear, but from one of the planet’s most abundant renewable resources: trees.

Known in the biz as “mass timber,” buildings made from good old-fashioned wood are lighter, structurally stable and better still, dramatically reduce carbon footprints. Timber can also significantly reduce construction time.

“Mass timber is really a strong example of how to apply natural principals to buildings,” said David Briefel, design resilience leader and sustainability director at Gensler architects’ NYC office.

“You use small [compressed] pieces as it allows the quicker growing trees to be harvested so you don’t need old-growth trees,” added Brent Buck of his eponymous architecture firm.

A man working on the Timber House.
Timber construction is light weight, reduces building time and gives off less carbon dioxide than traditional methods.
MESH Architectures

Although New York City developers and architects have been exploring the construction of 12- to 20-story mass-timber projects for several years, city code — which requires a special permit for wooden structures — is just not that limber regarding timber. Yet.

A new building code that allows for as-of-right shorter structures and new wood products known as “cross laminated timber” (CLT) arrives Nov. 7.

CLT is composed of at least three layers of either wood or structural composite lumber glued together perpendicularly. The layers are very thick — think 2-by-4s glued together. The resulting hunk can be flat or curved and can be prefabricated to as much as 60 feet long and 10 feet wide.

“This allows you to span in two different directions,” Briefel said.

Known in the biz as “mass timber,” buildings made from good old-fashioned wood are lighter, structurally stable and better still, dramatically reduce carbon footprints.

However, the new code will require these timber buildings to top out at just 65 feet or six stories unless an automatic sprinkler is included, which provides a 20-foot bump to 85 feet or seven stories.

Buildings of this size require an elevator, concrete-enclosed fire stairs and hallways — making them larger and more expensive to build, explained Vishaan Chakrabarti, founder of PAU, Practice for Architecture and Urban Planning.

The new timber code also requires sprinklers for residential buildings over three stories.
While it’s not as liberal as the International Building Code, which allows timber to rise to 270 feet or 18 stories, it’s a start.

In fact, a handful of short-scale timber projects in NYC already serve as proof of concept. The city already allows “glulam,” aka glue laminated timber (GLT), in certain instances, but architects say CLT provides more flexibility for designs.

Nearly a decade ago, architect Hugh Hardy designed the New York Botanical Gardens Leon Levy Visitor Center in The Bronx using mass timber for its stunning covered pavilions.

More recently, during the pandemic, Flank Architects opened 320 and 360 Wythe Ave. in Brooklyn as a timber post and beam warehouse-like office project with street retail. The three-story buildings each have ground-floor retail and two stories of offices. Retail rents range from $140 to $175 per foot with office asking rents at $65 per foot.

Interior of the Timer House.
Timber House at 670 Union St. in Park Slope is built with eco-friendly wood products.
Matthew Williams

Meanwhile, the Brooklyn Home Company along with Mesh Architects are now wrapping up construction on “Timber House,” a new six-story, 14-unit luxury condominium building with a shared roof deck at 670 Union St. in Park Slope.

The units were designed with a “modern tree house” aesthetic while incorporating solar photovoltaic panels and other green elements. Already 13 of the 14 units — including some with private terraces and views of Manhattan — are in contract for just over $1,580 per foot, as are most of the 11 parking spots. The remaining unit has three-bedrooms and 3½ baths in its 2,041 square feet and a tab of $3.2 million.

“All of the major rooms have exposed timber ceilings and you see the columns and beams,” said Eric Liftin, of Mesh Architects, a partner in the project. “You don’t have to clad the structure in other materials.”

Exterior of the Timber House.
Already 13 of the Timber House’s 14 units are in contract for just over $1,580 per foot.
MESH Architectures

Constructed using GLT under the prior building code, it also has a concrete foundation, stairs, elevator cores and lot line walls.

“I am very eager to do more buildings like this,” said Liftin, who is on the lookout for sites and hopeful the city will allow taller towers.

Brent Buck Architecture is currently designing a 15-unit residential project at 122 Waverly Place in Clinton Hill.

While at least 40 wooden structures are in the design phase across in New York State, the rest of the world, and even the rest of the country, is far ahead of NYC in terms of timber construction.

There are currently eight taller projects in the works and roughly 180 commercial wooden structures in development in the US, said Bill Parsons, COO of the Woodworks Innovation Network, a non-profit that provides technical support and catalogs the timber projects.

Exterior of the Ascent building.
At 284 feet high, Ascent in Milwaukee, Wis., is now the world’s tallest timber building. But for now, NYC building code only allows for 85-foot structures.
U.S. Forest Service

Since 2019, Norway had boasted the world’s tallest timber project, Mjøstårnet, with 18 stories and 280 feet that used concrete in its seven upper floors to stop the sway. But New Land Enterprises now has the record with its 25-story, 284-foot-high Ascent — a 493,000-square-foot apartment building in Milwaukee, Wis. It has seven parking levels with 18 stories of apartments now filling up at rents starting at just over $1,700 for a one-bedroom.

Not to be outdone, Danish architects Schmidt Hammer Lassen have designed Rocket&Tigerli, a terracotta-clad residential and mixed-use project with a tower hitting 328 feet to be built in Winterthur, Switzerland, near Zurich.

Jamestown, the Atlanta-based developer which operates Chelsea Market and owns 1 Times Square, is designing a prototype for a mid-rise mass-timber residential building that could end up in any one of a number of cities where they own land.

Why design a building without a home? That’s because mass timber enthusiasts are still waiting for state, city and local codes to catch up with the new building products.

“Finding the right spot,” Jamestown’s President, Michael Phillips, lamented, “is the challenge.”


Fire away!

Firefighters fight against the raging fire .
Safety experts carry a flame for mass timber.
Getty Images

When it comes to wood and city officials, “fire” is the scariest four-letter word.

But rigorous industry testing shows large wood beams are actually safer than many other building methods.

“The fire burns the exterior and the inside maintains its structural integrity,” said architect Brent Buck, who is working on a mass timber residential project in Brooklyn.

“Mass timber performs very well with fires because of the charring effect and because of the way they burn, their structural integrity is kept.”

David Briefel of Gensler architects

There’s even a black, thermally charred product “Ignite” — created without flaming by Thermory — with the look of the traditional Japanese “shou sugi ban.” It has a dragon-scale like finish and the company says it has added moisture and termite resistance.

Before allowing the 284-foot-high Ascent, Milwaukee officials and labs confirmed three-hour fire rating tests on its columns while the two-hour ratings for its door frames required using some metal. Penetrations through its glulam beams for pipes and wiring conduits were also concealed for fire purposes.

“Mass timber performs very well with fires because of the charring effect and because of the way they burn, their structural integrity is kept,” said David Briefel of Gensler architects’ New York office. “They also have good performance in seismic activity.”


Lumber lovers

Exterior of the High Line's mass-timber bridge.
The High Line will get a mass-timber bridge.
© SOM, JCFO | Miysis

In the first quarter of 2023, the High Line will have an addition that is a modern take on a mass-timber bridge dubbed “the Connector.”

Its two 600-foot-long spans will create a stroll from the Moynihan Train Station into Manhattan West and then either around the western edge of Hudson Yards or all the way to the Whitney Museum in the Meatpacking District — without setting a toe on a city street.

Designed by SOM and James Corner Field Operations, the project’s $50 million cost will be split by Friends of the High Line, Empire State Development and Manhattan West’s developer, Brookfield Properties.

First, the trestle-like “Timber Bridge” made of glulam wood will nestle seamlessly into Manhattan West’s Magnolia Court and run north-south along Dyer Street to West 30th Street.

Here, it turns 90 degrees west and becomes the “Woodland Bridge,” another 600-feet of trees and plants growing out of 5 feet of soil nestled in cast steel. This span, which is already in place, sits above the street and meets up with the main High Line at 10th Avenue.

“It will appear to be an elevated planter floating above the regular sidewalk,” said Kim Vanholsbeke, a design principal with SOM. “It will be a very unique addition.”



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