In this post we wanted to talk a little bit more about the Girder Truss, when it’s typically used and what it can be designed for. Girder Trusses have a long, straight design. Primarily, the role of a girder truss is to support other structural elements in the Timber frame, such as other trusses, rafters or purlins. For that reason, girded trusses are designed to be exceptionally strong and rigid. They are excellent for large buildings and look great with steel joinery.

Girder Trusses are required and/or chosen for all kinds of different timber framing applications. Let’s take a look at a few examples:

1. High End Residential  

This project used a girder truss to provide support to the arched glulams that span the great space. Isn’t this pretty?

Photo by David Bader

The frame is traditionally joined with extended joinery pegs.

Girder Truss / Photo by David Bader

2. Commercial / Recreation Project.

Sometimes we double up a girder truss and reinforce the joinery with steel for strength.  This is exactly the case for the Spruce Camp Base Lodge in Stowe, VT. The design asked for an 80ft octagon frame!

Double Chords / Girder Trusses

4 Girder Trusses in Place

Below is a peak from the inside of the finished building. The double girders all connect at the center of the frame.  How cool!

Spruce Camp / Ceiling Detail

Here’s a finished shot of the exterior.  This project is a favorite, no question.

Spruce Camp Base Lodge in Stowe

3. Commercial / Education Project.

This project has been renovated from a senior center to a school, now it’s the Concord Christian Academy.  The steel reinforced girder trusses didn’t go anywhere during the renovation.

Girder Trusses

Below, is a great shot of the trusses sitting at the shop ready to ship! The steel plates were not painted for this frame, which lightens up the design.

Girder Trusses / Ready to Raise

Below is how the exterior looks now. Would you guess there was timber frame construction in there?

Concord Christian Academy

Thank you for stopping by our Timber Framers’ Blog!

If you like the timber frames in this post, or have any timber work questions, we encourage you to get in contact, ask an expert, or share your thoughts in the comment section below!

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