Adimab

Mass Timber for Life Sciences

Tied to the increased understanding of the vibration performance of mass timber structural systems, one project under construction in the northeast has demonstrated the ability to meet market demand for more sustainable structures in the life sciences sector by utilizing mass timber construction materials.

When Adimab, a biotech company in NH, decided they needed to expand their facilities, they looked to create a multi-story timber structure to house new office, meeting, and lab spaces as sustainably as possible. In addition to using sustainable building materials, the project has also been designed with a robust thermal envelope.

Selecting the Right Structural System
The primary floor area is comprised of column and beam glulam construction that supports one-way spanning CLT floor and roof panels. While the project was afforded modest floor to floor heights, the high demands for systems distribution associated with a lab facility would have conflicted with the architectural goals of clean ceiling lines if this traditional construction approach was utilized throughout. Instead, the two-way spanning capabilities of CLT are leveraged to create a pathway of beam-free MEP distribution corridors throughout the building. With the selected framing layouts, most elements of the MEP system have an unobstructed pathway through the building, reducing the need for coordinated beam and wall penetrations, freeing up more head height and creating more visually appealing spaces.

Interior CLT bearing and shear walls are used selectively, in conjunction with the post and beam construction, to help support the structural approach while creating unique architectural moments in the space. These interior CLT walls are also used to supplement non-bearing exterior light framed wood shear walls detailed to resist lateral forces only. While CLT walls can provide unique advantages for exterior wall construction, light framed wood was selected to create highly insulated exterior walls with traditional detailing methods. However, to maintain a fast erection schedule the contractor preferred not to utilize the exterior as bearing walls. Special care was provided in detailing to ensure these exterior walls are compatible with the anticipated shrinkage of the timber structure and that they will not support unanticipated gravity loading.

Achieving Laboratory Vibration Performance
A concrete topping was selected to help meet acoustic and vibration goals of the project, however the CLT panels and plywood splines were used as the structural diaphragm to avoid the need for a thicker, structural concrete topping slab. With the effect of the non-composite and non-structural topping included, vibration analysis confirmed that the timber structure was adequate to create a high-frequency floor that could meet the needs of the client’s laboratory equipment without significant enhancements to the primary structure. This performance was attributed to multiple design decisions including a structural layout that respected timber’s naturally tighter grid in addition to isolating framing for corridors with higher walking speeds from the lab bench areas. Leveraging timber’s strengths in these ways demonstrates the possibilities for mass timber in life sciences construction.