DXR Drainback
Page 13
LAG BOLT MOUNTING
In lag bolt mounting you must locate the center of
the rafters along the top and bottom chalk lines.
One method is to have one person on the roof and
another in the attic. Using a hammer the person on
the roof can tap the roof and determine where it is
denser sounding. The roof person can drill a pilot
hole while the attic person helps with distance
corrections. Then the attic person can call off the
distance to the next rafter while the roof person
drills corresponding pilot holes. Flashing the
brackets is done as previously described. Secure
the brackets to the roof using a 3/8” x 3-1/2”
stainless lag screw, a flat washer, and a lock
washer.
NOTES:
•
Lag bolts are to be 3/8" diameter and must penetrate the rafter member a minimum of 3".
•
Pilot holes should be drilled into the centerline of the rafter and should be between 60-75% of the bolt
diameter.
•
Apply a liberal amount of roof sealant or a sealant pad around the opening prior to securing the mounting
bracket.
•
All connection hardware (bolts & washers) to be stainless steel.
PITCH PAN
The pitch pan is necessary any time standing water is
encountered. The purpose is to provide an adequate seal
around any penetration in the roof. The pitch pan is placed in
the proper position and flat on the roof. Its flange is sealed
with roofing felt and hot tar. The holes are sealed on the
inside with roofing tar to a sufficient level to insure a
permanent seal.
NOTE: All penetrations in structural members or fire
rated assemblies are to be made in accordance with local
codes using acceptable roofing practices.
In the mounting details shown on this and the preceding
pages, the term Triangular Mounting Bracket, Triangular
Bracket and Mounting Foot is used interchangeably and
references the same part.