SECTION 233113 - METAL DUCTS

Most sheet metal suppliers can provide a 4-mil- (0.10-mm-) thick coating on both sides. Minimum Thickness for Factory-Applied PVC Coating: 4 mils (0.10 mm) thick[ on sheet metal surface of ducts and fittings exposed to corrosive conditions, and minimum 1 mil (0.025 mm) thick on opposite surface]. ................
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