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 Section 2. PROCEDURES
While general procedures can be recommended, the location. identification
and description of the damage depends largely on the individual skill of the
inspector. An inspection team should consist of at least two individuals, one
inspector and one serving as an assistant for recording observations, handling
tools. etc.
2.2.1 VISUAL OBSERVATION. The general condition of heavy timber
trusses and glulam arches can be determined by visual observation. Some obser-
vations may indicate that more indepth study is needed, but much can be learned
by observing physical condition and signs of fungus and insect infestation.
2.2.1-A PHYSICAL. The most obvious indication of physical damage
is a sagging roof. If possible, sight along the top of the building to observe overall
visible sag as well as individual trusses or arches sagging more than those adja-
cent to them. Inside the building, sighting across the bottom chords of trusses
can reveal major sag of one truss relative to others. Also, sight along the base
of several glulam arches to see if there is outward deflection. Where trusses
appear to be sagging, the amount of sag should be measured. Simply measuring
the distance between the bottom chord and a level surface below may be possi-
ble where the "I" beam of a crane spans the width of the building. Measure
with a steel tape at each end and at the center. For distances more than 3 feet
between the lower chord and top of the crane, it may be necessary to use a plumb
line to assure vertical measurement. The amount of sag is the difference between
the center measurement and the end measurements. If no level surface is available
for reference, stretch a line between nails at each end of the lower chord and
measure the vertical distance between the lower chord and the line at the center
of length. Nails should be at the center of the bottom chord, and measurement
should be made to the center of the bottom chord.
Observe all splits in the wood members. Particularly note split in the con-
nector area and diagonal splits that extend to the edge of a wood member (see
section 3.1.2). Also look for fractures completely or partially through the cross
section of members. Check all glulam members for delaminations, and record
general location in the arch.
Look for separations between members at joints which indicate obvious
looseness of connectors. Also look for bolt holes where split-ring connectors
were intended but not installed (Fig. 2-1).
2.2.1-B DECAY. Decay may result in abnormal coloration of the wood.
The first indication of decay is often the appearance of brown streaks or blotches
(Fig. 2-2). As wood approaches advanced stages of decay, it loses luster and
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