ORD 2009-048 2008-2010 - Laserfiche WebLink

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8. L To qualify for the radiant barrier credit (RB) described in Subsection 8, the installation of the radiant barrier must meet the following criteria: 8.1.1. The emissivity of the radiant barrier must be 0.10 or less. The manufacturer must provide test data or documentation of the emissivity as tested in accordance with ASTM E-408. 8.1.2. The radiant barrier must be securely installed in a permanent manner using one of the following installation methods: 8.1.2.1. The radiant barrier shall be draped with the shiny side facing down over the top cord of the truss before the roof deck is installed. A minimum air gap of/a inch must be provided between the radiant barrier and the roof deck above at the center of the span. Aminimum'/4 inch air gap must also be provided between the radiant barrier and the ceiling or insulation below. 8.1.2.2. The radiant barrier shall be stretched with the shiny side facing down between the top cords of the truss and stapled or otherwise secured at each side. A minimum air space of/o inch above and below is required. 8.1.2.3. For attic installations only, the radiant barrier shall be stapled or otherwise secured to the bottom surface of the top cord of the truss and draped below with the shiny side facing down. A minimum air space of/n inch above and below is required. 8.1.2.4. For open beam ceiling construction only, the radiant barrier shall be laid on top of the roof deck with the shiny side facing up and a minimum '/4 inch air gap between the radiant barrier and the roofing material above. The roof slope must be greater than or equal to 14° from horizontal. 8.1.3. At least one square foot of free area for ventilation shall be provided per 150 square feet of attic floor area, or in the case of vaulted or open-beam ceilings, per 150 square feet of ceiling area. In vaulted or open beam ceilings, the air space shall be vented with vent area approximately evenly distributed between the top and the bottom. In vaulted ceilings, vents shall be provided for each air space between rafters." (7) Amending Table 402.1.3. Footnote b is added to Table 402.1.3 to read: "TABLE 402.1.3 EQUIVALENT U-FACTORS a Climate Fenestration Skylight Ceiling Frame Wall Mass Floor Basement Crawl Zone U-Factor U-Factor U-Factor U-Factor Wall U-Factor Wall Space U-Factor U-Factor Wall U-Factor 1 1.2 0.75 0.035 0.082 0.197 0.064 0.360 0.477 2 0.75 0.75 0.035 0.082 0.165 0.064 0.360 0.477 3 0.65 0.65 0.035 0.082 0.141 0.047 0.360 0.136 4 except 0.40 0.60 0.030 0.082 0.141 0.047 0.059 0.065 Marine 5