Sustainable Design in a Mass Timber Bunkhouse

Why a Mass Timber Bunkhouse?

The concept of the Mass Timber Bunkhouse exemplifies sustainability in design approach, materials used, and delivery of said materials. Located on a 4,000-acre working ranch, this 1927 barn replacement building is the place where ranchers will go to unwind. The design objective of the Mass Timber Bunkhouse is to incorporate efficient Cross-Laminated Timber (CLT) fabrication. This requires extensive coordination to minimize waste on a site with limited road access for large trucks and allows for expedited structural erection.

Benefits of CLT

The mass timber connections have a great level of detail, which were customized by the design team and the fabricator. The result is a primary structure that was erected in only five days, with hidden connections that feel intentional. This mating of architectural and structural detail is reminiscent of the type of craftsmanship seen in Europe.

Exposed structures provide many opportunities for the project to be delayed or fall apart entirely. It calls for design teams that can not only collaborate to solve challenges but also anticipate them. This pushed everyone to step out of their comfort zones.

The design team leaned into CLT material early on, since at the time of the design, CLT was not allowed to be used as shear walls. The CLT panels in this structure are used for bearing walls along the interior and the plywood sheathed exterior walls are used for the lateral system. This creates a double wall system with a gap of a few inches. Double walls work well for pocket doors and provide space for MEP runs. The architectural benefit of having a double wall system is that it keeps the exposed wood as the focal point in the structure and it reduces the finishes needed on the interior. Material excess was further reduced by pocketing beams into walls instead of using additional columns. The CLT floor and roof panels are used as diaphragms without any additional plywood – which is typically used in wood construction to transfer lateral forces to the exterior walls.

The exposed structure is architecturally used to define space within the first floor, with beam locations that cleverly segment a room. The Bunkhouse is artfully tied back together with a single continuous roof ridge beam that runs along its spine. The expressed CLT panels provide a pure and modern feel, which is subtle and not overpowering. This structure has a warmth that would be difficult to achieve with any other material.

The Final Product

The final product provides everything the owner dreamt of, along with a brilliantly coordinated structure, where everyone involved can feel a sense of accomplishment. From a material, delivery, and collaboration standpoint, the structure exemplifies smaller scale projects that are on the horizon. It provides designers with motivation to seek out these special moments and projects that value structural input into a sustainable and persevering future.