Ohio Administrative Code › Title 4101:8 - Board of Building Standards: Residential Code of Ohio › Chapter 4101:8-16 - Duct Systems › Section 4101:8-16-01 - Duct systems

Current through all regulations passed and filed through July 1, 2024
[Comment: When a reference is made
	 within this rule to a federal statutory provision, an industry consensus
	 standard, or any other technical publication, the specific date and title of
	 the publication as well as the name and address of the promulgating agency are
	 listed in rule
	 4101:8-44-01
	 of the Administrative Code. The application of the referenced standards shall
	 be limited and as prescribed in section 102.5 of rule
	 4101:8-1-01 of the
	 Administrative Code.]
SECTION
  1601
DUCT CONSTRUCTION
1601.1
Duct
  design.
Duct systems serving heating,
  cooling and ventilation equipment shall be installed in accordance with the
  provisions of this section and ACCA Manual D, the appliance manufacturer's
  installation instructions or other approved methods.
1601.1.1
Above-ground duct systems.
Above-ground duct systems shall conform to the
  following:
1.
											Equipment connected to duct systems shall be designed to
  limit discharge air temperature to not greater than 250°F
  (121°C).
2.
											Factory-made ducts shall be listed and labeled in
  accordance with UL 181 and installed in accordance with the manufacturer's
  instructions.
3.
											Fibrous glass duct construction shall conform to the
  SMACNA Fibrous Glass Duct Construction Standards or NAIMA Fibrous Glass Duct
  Construction Standards.
4.
											Field-fabricated and shop-fabricated metal and flexible
  duct constructions shall conform to the SMACNA HVAC Duct Construction
  Standards-Metal and Flexible except as allowed by Table M1601.1.1. Galvanized
  steel shall conform to ASTM A653.
5.
											The use of gypsum
  products to construct return air ducts or plenums is permitted, provided that
  the air temperature does not exceed 125°F (52°C) and exposed surfaces
  are not subject to condensation.
6.
											Duct systems shall
  be constructed of materials having a flame spread index of not greater than
  200.
7.
											Stud wall cavities and the spaces between solid floor
  joists to be used as air plenums shall comply with the following
  conditions:
7.1.
												These cavities or spaces shall not be used as a plenum for
  supply air.
7.2.
												These cavities or spaces shall not be part of a
  required fire-resistance-rated assembly.
7.3.
												Stud wall
  cavities shall not convey air from more than one floor level.
7.4.
												Stud wall
  cavities and joist-space plenums shall be isolated from adjacent concealed
  spaces by tight-fitting fireblocking in accordance with Section
  602.8.
7.5.
												Stud wall cavities in the outside walls of building
  envelope assemblies shall not be utilized as air
  plenums.
8.
											Volume dampers, equipment and other means of supply,
  return and exhaust air adjustment used in system balancing shall be provided
  with access.
TABLE 1601.1.1
DUCT CONSTRUCTION MINIMUM SHEET METAL
	 THICKNESS FOR SINGLE DWELLING
	 UNITSa
ROUND DUCT DIAMETER
				(inches)
STATIC
				PRESSURE
1/2-inch water
				gage
1-inch water
				gage
Thickness
				(inches)
Thickness
				(inches)
Galvanized
Aluminum
Galvanized
Aluminum
< 12
0.013
0.018
0.013
0.018
12 to 14
0.013
0.018
0.016
0.023
15 to 17
0.016
0.023
0.019
0.027
18
0.016
0.023
0.024
0.034
19 to 20
0.019
0.027
0.024
0.034
RECTANGULAR DUCT DIMENSION
				(inches)
STATIC
				PRESSURE
1/2-inch water
				gage
1-inch water
				gage
Thickness
				(inches)
Thickness
				(inches)
Galvanized
Aluminum
Galvanized
Aluminum
[] 8
0.013
0.018
0.013
0.018
9 to 10
0.013
0.018
0.016
0.023
11 to 12
0.016
0.023
0.019
0.027
13 to 16
0.019
0.027
0.019
0.027
17 to 18
0.019
0.027
0.024
0.034
19 to 20
0.024
0.034
0.024
0.034
For SI: 1 inch = 25.4 mm, 1 inch water gage =
	 249 Pa.
a. Ductwork that exceeds 20 inches by dimension
	 or exceeds a pressure of 1 inch water gage shall be constructed in accordance
	 with SMACNA HVAC Duct Construction Standards-Metal and Flexible.