Supporting Roof Rafters Without Kneewall

This article describes and illustrates the different types of support that prevents roof sagging and wall bulging at buildings including definitions of collar ties rafter ties and structural ridge beams.

Supporting roof rafters without kneewall. How to frame a gable roof without ceiling joists. In most instances they are no taller than 3 feet but some builders may custom fit them according to the roof s shape and size. Check that the 2 by 4 is plumb with a spirit level. In his book a visual dictionary of architecture francis d.

A knee wall is a short wall typically under three feet one metre in height used to support the rafters in timber roof construction. Install the second rafter leg in the same manner. Hold up to the rafter a scrap piece of 2 by 4 lumber a few inches longer than the planned knee wall height with its base on the floor. Ching defines a knee wall as a short wall supporting rafters at some intermediate position along their length the knee wall provides support to rafters which therefore need not be large enough.

You can see the image below for an example of a knee wall. A standard triangular roof known as a gable roof is framed using rafters which are diagonal members that support the roofing materials. Use a hammer and nails to fasten the new rafter to the old and drive nails through the rafter and into the ridge beam at its top end. Collar ties rafter ties tension beams structural ridge beams.