Roof frame - Building Your Straw Bale Home - page 154

Cutting and installing the hips
The next task is to fit the hips from the corner of the external walls up into the junction
of the rafters to the end of the ridge. You will first need to establish the angle that the end
of the hip has to be cut at so that it fits neatly into the junction of the rafters and the end
of the ridge. To do this you will need a string line and a bevel. A bevel is a tool that has an
adjustable blade that is held in position at virtually any angle by tightening a wing nut
(see Figure 8.28).

Figure 8.28 Adjustable bevel

Hip cut angles
Use a string line and bevel to establish the required angle of the hip cuts. Fix a string line
to the external corner of the outside wall. It is common for the birdsmouth checkout in
the hip to be 50 mm deep. Consequently, if
your hip is 200 mm deep, the position of
the string line is relative to 150 mm down
from the top of the hip. Measure 150 mm
down from the top of the ridge and make a
mark. Hold the end of the string line at this
mark and then use a bevel in the corner to
gain an angle from the end of the ridge to
the string line, as this will be the angle that
has to be cut on the end of the hip. The top
of the hip is to fit into the corner created by
the first rafter nailed at the end of the
ridge, and the rafter fixed to the end of the
ridge. To fit into this corner the top of the
hip will have to have angles cut on it (see
Figure 8.29).

Figure 8.29 Double 45-degree angle cuts for the top of
the hip beam