Here’s an interesting update on the international trend towards more wooden architecture. The French government is implementing a new sustainability law requiring all new public buildings to include at least 50 percent timber in their construction.
Set to be implemented by 2022, the law will affect all buildings financed by the French state, according to Agence France-Presse. The decision aligns with the country’s Sustainable City Plan, launched in 2009, which aims for France to be carbon-neutral by 2050.
“I impose on all the public establishments which depend on me and which make the development or the policy of land to build buildings with materials which are at least 50 per cent of wood or bio-based materials,” the country’s minister for cities and housing Julien Denormandie told the French news agency.
Taking Inspiration from the Olympics
Denormandie made the announcement following his seminar at the Living in the city of tomorrow event at UNESCO on February 5. He explained that building the 2024 Paris Olympics complex entirely from timber provided inspiration. “We made this commitment for the Olympic Games. There is no reason why what is possible for the Olympic Games should not be possible for the usual constructions.”
Dominique Perrault’s master plan for the Olympic Village will be located in the lower-income neighborhood of Saint Denis and feature a series of mid-rise passive or energy-plus developments made of wood or other sustainable materials, which could include hemp or straw. France’s first residential tower made from mass timber, Hyperion, is also expected to inspire new wooden buildings when it opens next year.
A Note on Fire Safety
When we talk about new large-scale timber projects, the most common question asked is, “but what about fire risk?” These kinds of wooden buildings are made from engineered wood like glulam, cross-laminated timber (CLT) and laminated veneer lumber (LVL). They’re light, strong, more sustainable than materials like concrete and steel, and yes, they’re designed to meet or exceed fire codes and standards. The reason we’re seeing more large-scale wooden architecture is that tests have proven the safety of these materials, leading to changes in building code around the world.
In fact, you can take it straight from firefighters. Here’s a brief snippet of an extensive piece on the fire safety of tall timber buildings.
“Most fires that occur in structures are room-and-contents fires, with the first material ignited being the contents of the room. As long as combustible building contents exist (e.g., furniture, computers, personal belongings, files), there will never be a truly non-combustible building. The building materials utilized in construction will never prevent a room-and-contents fire, but they must be able to resist the fire for an acceptable period of time. The automatic sprinkler system keeps the fire in check, preventing flashover, and the fire alarm notifies the occupants. Eventually, any building material will fail if the fire burns long enough. Steel will lose strength and fail, concrete will spall and fail, and wood will char and fail. That is why fire testing is essential for all building materials.”
“In December 2015, the ICC board of directors established an ad hoc committee of designers, code officials and members of the fire service, including firefighters, fire chiefs and fire protection engineers. Their task was “to research and design fire testing of mass timber and to draft code changes that ensure that tall mass timber buildings have redundant and rigorous fire safety systems that will protect the public that occupy tall mass timber buildings and the first responders that respond to them in emergencies.”
“The committee’s proposals identified a rigorous set of fire protection requirements that ensured that during reasonable fire events, no structural collapse will occur despite a complete burn-out of the room and contents. This performance is expected to occur even in the rare event of a sprinkler system failure. After two years of study, discussion, testing and analysis, the committee concluded that the proposals recommended would provide life safety protections to the public and first responders that are equal to or greater than tall buildings that are made of steel or concrete.”
For even more information, check out this update on the fire safety of timber construction at the Building Products Digest.
