Appendix E: Alternative Roof Designs
(Carpentry)The collar tie roof was originally designed to amplify the space in attics, to use as storage space or an
extra room. The collar tie, bar in the middle, would be placed between every other shaft to distribute
the weight of the roof. The drawbacks on this design is that, with stress and time, the collar tie will
suffer deformation and have to be replaced.
The diagonal bracings are typically metal bars that are connected to the bottom chords to give an extra
reinforcement to the roof, especially in resisting vertical forces, the picture below shows how the
bracings are connected to the bottom chords.
(worker)??The diagonal bracing design is mostly used to reinforce the roof instead of substituting other designs.