Rafters And Roof Ridges Are Normally Under Tension

That s true for horizontal ties in the lower third of the roof.

Rafters and roof ridges are normally under tension.

Rafter tie a tension tie in the lower third of opposing gable rafters that is intended to resist the outward thrust of the rafter under. The roof framing mock up below shows a standard rafter tie. A pair of rafters is called a couple in home construction rafters are normally made of wood exposed rafters are a feature of some traditional roof styles. It s an indication that you should look carefully for other problems in the roof framing.

If you see rafters installed on centers greater than 24 inches look for signs of failure such as sagging of the rafters. A rafter tie is a tension tie in the lower third of opposing gable rafters that is intended to resist the outward thrust of the rafter under a load. Mathematicians and engineers discussing collar ties and rafter ties explain that collar ties and rafter ties or ceiling joists under a gable roof are in enormous tension and that the mathematics of the roof forces are the same for collar ties and rafter ties. A rafter is one of a series of sloped structural members such as wooden beams that extend from the ridge or hip to the wall plate downslope perimeter or eave and that are designed to support the roof deck and its associated loads.

If you see sagging rafters recommend stabilization by a qualified contractor. A tension tie in the upper third of opposing gable rafters that is intended to resist rafter separation from the ridge because of wind or unbalanced roof loads. A ridge board was not always required and the photo above of the attic in a 1920s era house shows a roof framed without one. In many situations you ll find that ceiling joists installed parallel to the rafters are intended to function as rafter ties.