David L. Chandler | MIT News Office
A new building about to take shape in Boston’s Roxbury area could, its designers hope, herald a new way of building residential structures in cities.
Designed by architects from MIT and the design and construction firm Placetailor, the five-story building’s structure will be made from cross-laminated timber (CLT), which eliminates most of the greenhouse-gas emissions associated with standard building materials. It will be assembled on site mostly from factory-built subunits, and it will be so energy-efficient that its net carbon emissions will be essentially zero.
Most attempts to quantify a building’s greenhouse gas contributions focus on the building’s operations, especially its heating and cooling systems. But the materials used in a building’s construction, especially steel and concrete, are also major sources of carbon emissions and need to be included in any realistic comparison of different types of construction.
Wood construction has tended to be limited to single-family houses or smaller apartment buildings with just a few units, narrowing the impact that it can have in urban areas. But recent developments — involving the production of large-scale wood components, known as mass timber; the use of techniques such as cross-laminated timber; and changes in U.S. building codes — now make it possible to extend wood’s reach into much larger buildings, potentially up to 18 stories high.