Results 1 to 4 of 4
02-24-2010, 07:19 AM #1
Metal duct near crawl space floor
The home was remodeled in 04. This duct was about 2 inches off the ground. Is the clearance requirement 6? I know they spared no exspense on the support.
02-24-2010, 08:00 AM #2
Re: Metal duct near crawl space floorM1601.3.2 Support.Metal ducts shall be supported by
1/2-inch (13 mm) wide 18-gage metal straps or 12-gage galvanized
wire at intervals not exceeding 10 feet (3048 mm)
or other approved means.
M1601.3.4 Duct insulation.Duct insulation shall be
installed in accordance with the following requirements:
1. A vapor retarder having a maximum permeance of
0.05 perm [(2.87 ng/(s m2 Pa)] in accordance with
ASTM E 96, or aluminum foil with a minimum thickness
of 2 mils (0.05 mm), shall be installed on the
exterior of insulation on cooling supply ducts that
pass through nonconditioned spaces conducive to
2. Exterior duct systems shall be protected against the
M1601.3.6 Duct separation.Ducts shall be installed with
at least 4 inches (102 mm) separation from earth except
where they meet the requirements of Section M1601.1.2.
M1601.1.2 Underground duct systems
' correct a wise man and you gain a friend... correct a fool and he'll bloody your nose'.
02-26-2010, 08:37 AM #3
Re: Metal duct near crawl space floor
I can't remember how many metal ducts I've seen rusted from being on or close to the crawl space floor. None of them were properly supported. They use duct tape and coat hangers. Same thing with the flexable ducts...except with severe bends.
02-26-2010, 09:49 AM #4