(a) Air distribution, exhaust and air handling systems, except as qualified below, shall be installed in accordance with applicable provisions of the Ohio Basic Building Code (Mechanical), Article 3 [OAC 4101.2-35] and SMACCNA "HVAC" duct construction standards for metallic ducts and for design guidelines (refer to Appendix A).
(b) Ductwork shall be constructed of galvanized steel, aluminum or copper with gauges or thicknesses as recommended in the reference standards. Fiberglass ductwork is not permitted except upon approval by the Building Inspector in locations which are not accessible and where damage cannot occur.
(c) Ductwork shall be isolated in such a manner as to prevent noise and vibration transmission to the structure. Flexible connectors are required at the duct connection to air handling and air moving equipment which may generate noise or vibration.
(d) The air distribution system shall be engineered and installed to provide for the distribution of sufficient quantities of air and at the required temperature to provide for uniform conditions in all rooms without objectionable drafts or noise.
(e) Ductwork joints shall be sealed with two-inch wide duct tape where required to prevent excess air leakage.
(f) All branch ducts and take-offs for run-outs shall be tapered transition-type or with extracting vanes. Accessible balancing dampers with locking quadrants and identification tags shall be installed in all branches and run-outs.
(g) Ductwork shall be thermally insulated in all nonheated and nonconditioned spaces, and in those locations where surface condensation could occur and result in damage. Insulation shall also be applied as necessary to prevent changes in the air temperature which would adversely affect the performance of a system. See Section 1385.07.
(h) All wall penetrations for outside air intakes for exhaust systems shall be sleeved, sealed around the perimeter, louvered and screened or protected to prevent water, snow or pests from entering the ductwork system or the building.
(i) Below-grade or below-floor ductwork shall be constructed using noncorroding material and a sheet metal that is coated or otherwise protected to prevent water infiltration or deterioration. Below-grade joints shall all be taped and ductwork fully encased in a minimum of two inches of concrete.
(j) Below-grade ducts shall be pitched to an accessible sump or drain to provide for removal of any water that may collect in the ductwork.
(k) At duct penetration of fire-rated walls or partitions, UL-rated fire dampers and access doors or panels for service shall be installed. The damper construction and installation shall be to NFiPA Standards (refer to Appendix A).
(l) Where stud or joist spaces are used for return air, sleeved floor penetration headers and air stops shall be included as required.
(Ord. 1992-101. Passed 1-14-92.)