ASHRAE-90.1-2022- - Page 063

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mined in accordance with NFRC 300 and NFRC 301, determined by an independent laboratory or included in a database published by a government agency, and certified by the manufacturer . 2. Fenestration not covered in the scope of the NFRC 200. 3. Enclosed spaces where the daylight area under roof monitors is greater than 50% of the enclosed space floor area. 4. Enclosed spaces with skylights that comply with Section 5.5.4.2.3. 5. Enclosed spaces where the sidelighting effective aperture is greater than or equal to 0.15. 6. For dynamic glazing, the VT / SHGC ratio and the LSG shall be determined using the maximum VT and maximum SHGC . Dynamic glazing shall be considered separately from other fenestration, and area-weighted averaging with other fenestration that is not dynamic glazing shall not be permitted.

5.5.5 Linear Thermal Bridges and Point Thermal Bridges. Where linear thermal bridges and point thermal bridges occur as described in Sections 5.5.5.1 through 5.5.5.5, they shall

a. comply with the applicable requirements of Sections 5.5.5.1 through 5.5.5.5 or

Informative Note: For linear thermal bridges and point thermal bridges that fall under the provisions of Section 4.2 and cannot comply prescriptively with the provisions of Sections 5.5.5.1 through 5.5.5.4, projects can use Section 5.5.5.5, Section 12, Normative Appendix C, or Normative Appendix G.

5.5.5.1 Roof and Wall Intersections. Where a roof with insulation entirely above deck intersects an

5.5.5.1.1 Roof Edges. At roof edges without parapets or overhangs, the roof insulation and the wall insulation shall comply with the following, as applicable to the location of the insulation:

a. Where a wall has exterior continuous insulation, the roof insulation shall extend to the exterior of the

wall insulation and the wall insulation shall extend to the roof insulation. b. Where a wall has cavity or integral insulation that represents more than 50% of the total wall insulation

R-value, the roof -to-wall insulation shall comply with one of the following:

1. The cavity or integral insulation shall extend to the underside of the roof insulation.
2. The cavity or integral insulation shall extend to the underside of the roof deck, and the roof insulation shall extend to the exterior face of the wall . The wall insulation shall be permitted to be interrupted by roof framing members.
3. Additional insulation having a rated R-value of insulation not less than R-5 shall extend inward on the underside of the roof deck for not less than 2 ft and be permitted to be interrupted by roof framing members.
4. Insulation having a rated R-value of insulation not less than R-5 shall be placed at the exterior of the roof edge and be located between the bottom plane of the roof insulation and the plane of the bottom of the roof deck.
5. The wall insulation values in Tables 5.5-0 through 5.5-8 shall be adjusted in accordance with Table 5.5.5.1.1-1.
6. The roof insulation values in Tables 5.5-0 through 5.5-8 shall be adjusted in accordance with Table 5.5.5.1.1-2.

ANSI/ASHRAE/IES Standard 90.1-2022 (I-P) 61

Exceptions to 5.5.5:

1. Buildings located in Climate Zones 0 through 3.

2. Semiheated spaces in buildings located in Climate Zones 0 through 6.

3. Thermal bridges in uninsulated assemblies.

4. Linear and point thermal bridges that have a material thermal conductivity less than 3.0 Btu·in/ h·ft [2] ·°F.

5. Alterations to existing buildings other than additions.

6. Roofs that project over exterior walls.