Supporting Roof Rafters Without Knee Wall

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 knee wall.

You can see the image below for an example of a knee wall. In his book a visual dictionary of architecture francis d. 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. 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.

In a sloped roof common rafters run from the peak of the roof down to the top of the exterior walls of the building. Collar ties rafter ties tension beams structural ridge beams. Knee walls are short usually wooden walls installed around the sides of an attic where the rafters meet the floor. Check that the 2 by 4 is plumb with a spirit level.

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. Some of these can support the roof and prevent ridge sagging and wall spreading. A knee wall is a short wall typically under three feet one metre in height used to support the rafters in timber roof construction. Without support for those spliced boards they ll collapse downwards.