How to Strengthen a Steel Truss

Increase the amount of webbing in the truss. The truss "webbing" describes the truss members which are installed at angles between the top and bottom cords. Increasing the number of web members will strengthen the load-carrying capacity of a truss. The new webbing can be new rebar, or steel bar stock. Flat bar stock is less effective since it will bend when compressed.

Reinforce the truss joints with truss plates. Steel trusses are manufactured with flat steel plates on each joint. These plates distribute the load carried by each joint. By increasing the thickness of the truss plates, or increasing the overall size of the plates, the truss will be strengthened. In some cases a truss plate can be bolted or riveted into place. In other cases, the existing truss plate has to be removed and a new one installed in its place. Determining the appropriate method depends on the existing truss' configuration.

Rivet additional steel channel along the top or bottom cord of the truss. The top and bottom cord, in compression and tension respectively, carry the main load of the truss. These members are riveted into the truss, and cannot be removed and replaced while the truss is in place. The cords can be strengthened by riveting c-channel or t-shaped bar stock along the entire length of the cord.