Chester Congregational Church is a Greek Revival cutie with a facade that can stop traffic. It was originally built in 1773, 90 degrees to its current orientation, with a tower that stood proud of the end bent, an open belfry, and eight-sided spire. In the 1840s, the building was turned, the tower was enclosed within the body of the church, and a narthex was added, with an enclosed belfry and four-sided, oblique spire. In 2018, PTF was called to assess the building, and investigate damage to the tower frame. In the attic, we encountered an incredible queen post truss system.
A queen post truss allows a church to have a large open sanctuary, uninterrupted by interior posts. The vertical queen posts support the bottom chord, which stretches from eave wall to eave wall. King post trusses are common in late 18th and 19th century churches, but a modified queen post truss like this one is rare. This truss contains two queen posts connected by a horizontal strainer, and braced by two upper chords, which are the diagonal timbers running parallel inside the rafters. The trusses are connected down the length of the building by a sturdy series of girts and ascending braces. They are further stabilized by those big, long logs running the length of the building. Those were likely used to help erect the frame, especially the front tower.
The belfry tower posts were in more trouble. Previously, this corner had been stabilized with metal gussets. Unfortunately, large plates of metal can cause ambient moisture to condense against the posts, and prevent them from drying out, exacerbating the rot.
The post was badly rotted behind the metal plates, and required a timber scarf repair. Additionally, the horizontal bed timbers supporting the spire were rotten, and needed to be replaced. The design of the tower frame is unusual, the bed timbers rest on a ring of girts that run just below the tower top plates; the beds are sandwiched between the two rings of timbers.
In order to replace the bed timbers and repair the belfry posts, we removed the spire to the ground. It can seem dramatic to remove a big piece of the building, and can spook the congregation, but ultimately, this was the most efficient (and economical) way to repair the tower. With that weight on the ground, we were able to make repairs without setting staging and rigging through the center of the sanctuary.
Arron repaired the corner post with this custom scarf joint, which preserved good original material and joinery. Timber repairs are the most effective and longest-lasting way to repair an old frame. Metal plates will lead to further rot, and many (but not all) metal brackets are not strong enough. We find scarf joints like these in many old frames, old repairs that have lasted for centuries. We cut the same scarf joints with the benefit of power tools. These days, Arron, our boss, doesn’t get out in the field as much as he would like, but he cut this scarf himself. Dan whispered to me that the fix fit on the first try, no kerfing required. Turns out Arron’s still got it.
A few of the girts and plates were replaced as well. The new top plate was joined to the old using a floating tenon, which is a like a big spline, fastened with oak pins. We find that wooden mortise-and-tenon joinery is stronger and longer-lasting than modern brackets and fasteners. All wood moves over time resulting in metal fasteners working free, which is dangerous if the fasteners are the only thing supporting your girt. We generally use metal fasteners as tension connectors, and timber joinery to support the weight of the frame. We reproduce joinery that has been proven over time, or improve the joint so that the girt is solidly supported on the post, compensating for any shrinkage. Here, the girts supporting the bed timbers receive a little extra help from new studs within the wall plane.
Unfortunately, our crew, Dan, Erik, Tom W., and David G., have been working so fast and have been so focussed on repairs that they neglected to take any pictures of the spire’s return to its aerie. A crane placed the old spire on its new bed timbers on September 16, 38 days after it was removed. Ultimately, spire removal was the speediest road to recovery, and the church can continue to stop traffic.
The Union Leader covered the raising here, and they have some great pictures.
