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Step-Off Calculations and Layout | Up
Builder 3&2 Volume 02 - Construction manual for building structures | Next
Figure 2-25.-Setting up and bracing a ridgeboard when only a few workers are available. |
Figure 2-23.—Calculation for a collar tie.
The material used for the ridgeboard is usually
wider than the rafter stock. For example, a ridgeboard
of 2- by 8-inch stock would be used with rafters of 2-
by 6-inch stock. Some buildings are long enough to
require more than one piece of ridge material. The
breaks between these ridge pieces should occur at the
center of a rafter.
One pair of rafters should be cut and checked for
accuracy before the other rafters are cut. To check the
first pair for accuracy, set them in position with a 1
1/2-inch piece of wood fitted between them. If the
rafters are the correct length, they should fit the building.
If, however, the building walls are out of line,
adjustments will have to be made on the rafters.
After the first pair of rafters is checked for accuracy
(and adjusted if necessary), one of the pair can be used
as a pattern for marking all the other rafters. Cutting is
usually done with a circular or radial-arm saw.
COLLAR TIE.— Gable or double-pitch roof
rafters are often reinforced by horizontal members
Figure 2-24.—Laying out end cut on a collar tie.
2-16
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