Mass timber is all over the news, and you might be asking how sustainable it is. Our Kirksey mass timber experts have answers!
1. Mass timber is 5x lighter than concrete and 15x lighter than steel. We saved time, cost, and energy by reusing the existing foundation on one of our recent mass timber projects.2. Embodied carbon is the carbon dioxide emissions from a building’s materials, including what it takes to make the materials, transport them, place them within the structure, and even what it will take to dispose of them at the end of their life. The San Jacinto College Classroom building has less than half of the embodied carbon of a standard educational building because of its mass timber construction.
3. Wood has a comfortable surface temperature and the ability to compensate for rapid fluctuations in temperature and humidity.
4. Trees absorb carbon from the atmosphere as they grow. Wood is composed of 50% carbon by dry weight. Every cubic meter of wood stores approximately 0.9 tons of CO2. Buildings constructed with wood will sequester the carbon for the entire life of the building and longer if the wood is recovered and reused or repurposed.
5. Wood requires less energy to manufacture than other materials. Studies accounting for long-term carbon dynamics of wood products shows that the substitution effect of avoiding fossil fuel emissions is even more significant than carbon stored in wood.
6. Mass timber products may perform better in a fire than non-combustible materials. When exposed to fire, the outer layer of mass timber burns and creates a protective charring layer. Mass timber structural members are designed with extra thickness to allow for charring.
7. Using wood instead of other materials like steel or concrete helps create healthier forests. Using small pieces of lumber for the floors and beams instead of large timber pieces allows manufacturers to leave large trees in the forest. Large trees are better at absorbing carbon from the atmosphere and can help reduce fires and allow the remaining trees to flourish.
8. The carbon emissions associated with one of our mass timber projects is approximately 3,756,742 kg of CO2 equivalent, compared to 9,110,675 kg of CO2 equivalent if the building had been designed with a concrete structure. This quantity of mitigated carbon emissions is equal to the following:
- greenhouse gas emissions from 1,154 gasoline-powered passenger vehicles driven for one year
- CO2 emissions from 602,455 gallons of gasoline consumed, or 1,042 homes’ electricity use for one year
- greenhouse gas emissions avoided by 1,853 tons of waste recycled instead of landfilled
- carbon sequestered by 6,336 acres of US forests in one year, or 88,528 tree seedlings grown for ten years
Steve Durham, AIA, LEED AP
Michelle Old, AIA, LEED AP
Darrell Whatley, AIA, LEED AP