Appeal 13518
Appeal Summary
Status: Decision Rendered
Appeal ID: 13518
Submission Date: 5/27/16 4:14 PM
Hearing Date: 6/1/16
Case #: B-012
Appeal Type: Building
Project Type: residential
Building/Business Name: Mutal Residence
Appeal Involves: Erection of a new structure
Proposed use: residential Accessory Dwelling Unit
Project Address: 7221 SW Virginia Ave
Appellant Name: brett crawford
LUR or Permit Application #: Permit 15-243740-RS
Stories: 3 Occupancy: R-3 Construction Type: Type V-B
Fire Sprinklers: No
Plans Examiner/Inspector: Maureen McCafferty
Plan Submitted Option: pdf [File 1] [File 2] [File 3] [File 4] [File 5]
Payment Option: mail
Appeal Information Sheet
Appeal item 1
| Code Section | ORSC Chapter 11 Table 1101.1 |
|---|---|
| Requires | Wall Insulation above grade shall be minimum R-21. |
| Code Modification or Alternate Requested | |
| Proposed Design | Wall Assembly 7 for the Exterior Wall Assembly for the accessory dwelling unit (ADU) Structure includes: • R-17 for rigid mineral wool, exterior continuous insulation - 4-1/4 inch rock wool insulation at R-4 per inch. Total R-Value for wall assembly is R-22.4. Reference attached CLT Handbook U.S Edition - Chapter 10, Page 9, Article 2.1.4 - Heat Storage and Heat Transfer and Table 2 - Thermal Resistance of typical softwood at various thicknesses and 12 percent moisture content. Prepared by U.S Forest Product Laboratory and RDH Engineering. |
| Reason for alternative | Proposed wall assembly utilizing CLT Framing in cooperation with continuous exterior mineral wool insulation. This provides for an effect/actual R-value of R-22.4, in lieu of a nominal report of R-21 as prescribed with standard insulated wood stud framing. Wall Assembly 7 for the Exterior Wall Assembly for the ADU Structure includes: • R-17 for rigid mineral wool exterior continuous insulation - 4-1/4 inches rock wool insulation at R-4 per inch. Total "effective" R-Value for wall assembly is R-22.4. |
Appeal Decision
Equivalent Energy Performance of Cross Laminated Timber Exterior Wall Assembly with Mineral Wool and Continuous Exterior Insulation to R-21 Batt Insulation: Granted as proposed.
The Administrative Appeal Board finds that the information submitted by the appellant demonstrates that the approved modifications or alternate methods are consistent with the intent of the code; do not lessen health, safety, accessibility, life, fire safety or structural requirements; and that special conditions unique to this project make strict application of those code sections impractical.
Pursuant to City Code Chapter 24.10, you may appeal this decision to the Building Code Board of Appeal within 180 calendar days of the date this decision is published. For information on the appeals process and costs, including forms, appeal fee, payment methods and fee waivers, go to www.portlandoregon.gov/bds/appealsinfo, call (503) 823-7300 or come in to the Development Services Center.