Straining Beam (Timberbee)

From the Quicksilver Metaweb.

An essential element of the Queen Post Truss.

It sits between the two Queen Posts, just below the upper tennons – which support the Purlin Plates, and across from the Main Braces.

In a fully loaded Truss, it exists in Compression, resisting the desire of the Queen Posts to fall inward, due to the force exerted upon them by the braces.

In some Trusses the Straining Beams sit within housings set in the tops of the Queen Posts, with no benefit of either Straps, or a Mortise and Tennon joint, to keep them in place. Requiring the load of the roof to maintain the structural integrity of the Truss.

This makes for grand surprises when the Trusses are unloaded to effect repairs.