By Jeremy Sanders, Stephen Morrison, Carol Greenberger (MoreSun Timber Frames)
Structural Engineers: Brown + Kubican
Builder: Anderson & Rodgers Commercial
Timber Framer: MoreSun Timber Frames
Preserving historic structures is one of the most rewarding aspects of being a timber framer, so we were thrilled to be contacted about rebuilding a Civilian Conservation Corps (CCC) pavilion at Pine Mountain State Park in Pineville, Kentucky. The park opened in 1924 as Kentucky’s first state park, and in 1933, the CCC constructed the round log timber framed pavilion atop Kentucky sandstone walls.
Our mission was to create a replica of the structure and raise it on the existing walls. Early on, we thought we would be able to salvage and reuse much of the original structure, based on photos taken by the local contractor. However, when we made a site visit, it became clear quite quickly that very little could be saved: you could stick your finger right into most of the logs! Eight short poplar pieces ended up being reused as knee braces, but that was about all we could do with the materials on-site.
We undertook demolition, disassembled the original roof system, and did field measuring and surveying. We kept a few token pieces of the original pavilion, the local contractor kept a few, and the park kept the rest of the salvageable pieces for repair work on other structures.
The original structure was built with 14 x 18″ plates, hewn on two sides, primarily oak. The 6–8″ round log rafters and truss members were mostly poplar. The engineer stressed that when ordering timbers, we should err on the side of bigger, and so we ultimately used 16 x 20″ plates and 10–12″ rafter and truss members. To keep the pavilion as true to the original as possible we sourced new white oak logs from Kentucky. Needless to say, none of the pieces could be moved by hand, which added to the difficulty of this project.
The plates came first, and were half-lapped at their joints. Once assembled, we squared the plate system based on the centerlines that were snapped at the top of each timber. These plate centerlines were crucial to the entire process: we used them to reference the bird’s mouth joinery on the rafters as well as the mortises that housed the thrust blocks required at each rafter location. The thrust block idea was new to us. A piece of oak, roughly 4 x 4 x 6″, was routed into the bottom of the rafter and into the top of the plate to create a heel to hold against the thrust of the rafter. It was not an easy piece to get just right, and we’d prefer not to use it again.
Of course, creating a square building, with a consistent roof plane, with mostly round timber is challenging. When you couple that challenge with a rushed schedule, you’d better come up with some good, repeatable systems for cutting. All the joinery could be cut with chainsaws, and we decided to assemble the whole structure in our shop yard as we cut each piece, allowing us to check our systems and make adjustments as we went along.
When the time came for cutting the roof system, we divided our crew into teams. One team cut and assembled the four trusses designed to resist the spreading force imposed by the roof onto the plate system. Another team worked on cutting common rafters. Still another team worked on sorting out hips and jack rafters. Templates were employed to ensure consistent joinery on both peaks and tails of the rafters, while allowing for speedy production. Trusses were scribed together, laid up over centerlines that were snapped on the concrete shop floor.
As a truss was completed, it was moved out of the shop and placed on the structure, making room for another to be scribed. As a set of common rafters was cut, it was assembled on the structure. When all common rafters were cut and assembled, the common rafter team moved into cutting jack rafters, which were well underway.
One member of our team was dedicated to hardware installation during the entire assembly. The engineering of the project required a through-bolt (in addition to the aforementioned thrust block) at each rafter to plate connection. This required a 25″-long hole to be drilled through the rafter and the plate, along with countersink holes to recess the hardware. Bolts were also required through the half-laps at the rafter peaks. The jack to hip connections required two RSS screws, several of which broke off in the grip of the white oak as we disassembled the structure.
Most of the assembly done in our yard was done in the rain (and we were the talk of the town). The project had a very tight schedule, and needed to be completed, with roof and all, before the Kentucky Governor’s annual party in the pavilion in late March. So, once we disassembled the structure we loaded up two trucks and headed straight to the state park. The site lacked any good flat spots to assemble the trusses, and the trucks carrying the timbers could only make it to about 200 yards from the site. The timbers had to be moved one at a time, slung from a forklift, through a narrow path, across a creek and up a hill.
Once we got started on-site the crew worked ten days straight, determined to get it done. They did get to scope out the park, which has a beautiful CCC-built lodge, nice cabins, great trails, and a zip line. One night they enjoyed the “Frontier Dinner” at the lodge, complete with bison, elk, and frog legs. Without each member of the team, this project could not have been completed on time.
Challenging projects help us learn and grow, improving our skills and teaching us new techniques. Each person who helped on this job contributed in some way, large or small, to its success. Knowledge we have gained from the Timber Framers Guild has helped on this and every other project we work on. And now it’s on to the next one!