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20091216074447844.pdfI,? C. 1890 CITY OF EDMONDS 121 5TH AVENUE NORTH • EDMONDS, WA 98020 • (425) 771-0220 • FAX (425) 771-0221 Website: wwwdedmonds.wa.us DEVELOPMENT SERVICES DEPARTMENT Planning • Building • Engineering December 15, 2009 John Thoresen Sunset 100, LP 1611872 n1 Ave W Edmonds, WA 98026 RE: Request for Building Code Interpretation 121, 123, 125 Sunset Ave N Dear Mr. Thoresen, GARY HAAKENSON MAYOR This letter is in response to a letter from architect Brian Corbett, dated April 7, 2009, received by the City on December 2, 2009. Based on his letter it is our understanding that the subject exterior stairway and landing will only be located between the north and middle buildings (Buildings B & C on the approved plans), specifically between 123 and 125 Sunset Ave N. As noted in previous City letter dated April 2, 2009, we have read the report and have determined that the engineer has adequately justified that the proposed exterior stairway landing area between the two buildings can be considered pedestrian walkways as set forth in IBC 3104 to address fire separation issues. Based on the architect's letter it is our understanding that the landing and stair will be self-supporting with no attachment to either building in order to utilize exception 2 to IBC 3104.2. This will be confirmed during review of the revised architectural plans and shop drawings (shop drawings must contain the shop drawing review stamped approved by the structural engineer of record). Please submit 3 sets of revised architectural plans and shop drawings reflecting the stairway/landing changes. Also, we are still awaiting revised architectural plans in response to Plan Review Comments dated April 17, 2009 (copy enclosed). This was due to the changes made to the parking garage area. Please include these changes in the revised architectural plans to be submitted to the City for review. Sincerely, Ann Bullis, CBO Building Official • Incorporated August 11, 1890 • Sister Citv - Hekinan. JaDan of EDV l..ity of Edmonds PLAN REVIEW COMMENTS BUILDING DIVISION (425) 771-0220 DATE: April 17, 2009 TO: Duane Landsverk duane@lqh-ine.com FROM: Ann Bullis, Building Official RE: Revision to Permits 2008 0463, 2008-0464, 2008-0465 Project: Sunset Condominiums –,Architectural Revision to Lower Floor Project Address: 121, 123, 125 Sunset Ave N During review of the revised architectural plans for the above noted project, it was found that the following information, clarifications or changes are needed. Please provide written responses as to where the changes can be found on the plans, and submit revised plans/documents to a Permit Coordinator. 1. Revised Sheet A-1 shows a reference to detail 101A-1 at the northeast corner of the building which could not be found. Please provide the detail on the plan. 2. Submit revised Sheet A-0 showing the revised floor area for the lower floor. cc: Brian Corbett via email: r brian@—msn.com AE61 S ENGINEERING March 24, 2009 Mr. John Thoresen Sunset 100 LP 16118 72nd Ave W. Edmonds, WA 98026 SUNSET PROJECT - EDMONDS EXTERIOR STAIR CONDITION Dear Mr. Thoresen: ILY/rAVv_r —4w1ok 6725 162nd Pl SW Lynnwood, WA 98037 www.AegisEngineering.com (425) 745-4700 fax (206) 801-5797 MEE: I E I 2 4 2006 Aegis Engineering has been retained by Sunset 100 LP to evaluate exterior stairs located between buildings at the Sunset Project in Edmonds, at 121, 123, and 125 Sunset Ave N. We understand this project is subject to the 2006 International Building Code (IBC) as adopted and amended by the State of Washington and enforced by the City of Edmonds. BACKGROUND The Sunset Project consists of three Type VB Group R-3 structures situated atop a Type I underground parking garage, separated in accordance with Section 509.2 by 3 -hour fire -resistance -rated construction. The project is equipped throughout with an approved automatic sprinkler system. Each Group R building is separated by 6 feet. An assumed property line is extended between the buildings such that the fire separation distance varies from less than 5 feet to greater than 5 feet to accommodate exterior window and door openings. Exterior walls are 1 -hour fire -resistance rated from both sides in accordance with IBC Section 704.5. The Group R-3 structures are two -stories, with up to 2 dwelling units; one dwelling unit on the main floor and a second dwelling unit on the upper floor. The primary ingress and egress access for each unit is from the east in accordance with Item 2 of IBC Section 1019.2. An additional stair is proposed within the 6 -foot space between the north and central buildings to serve the two upper dwelling units. This supplemental stair and landing would be of noncombustible construction. No openings are proposed Fire Protection - Building Code Consult - Design - Engineer SUNSET 100 LP SUNSET PROJECT - EDMONDS EXTERIOR STAIR CONDITION Page 2 March 24, 2009 beneath the stair element, or facing the stair other than for access from units served by the stair. EVALUATION Aegis Engineering has evaluated the proposed conditions at the Sunset Project with regard to applicable provisions of the IBC. BUILDING AREA The code generally seeks to limit the magnitude of potential conflagrations through compartmentalization and regulating the size of buildings. However, at the Sunset Project, the individual buildings are classified as Group R-3 buildings, which are permitted to have an unlimited area. This suggests that the code recognizes an inherently low level of risk to be associated with Group R-3 construction. If multiple Group R-3 buildings at the Sunset Project were considered together as Group R-2, the actual area of the two subject adjacent buildings could be considered portions of a single building in accordance with IBC Section 503.1.2. As the code would permit two buildings to be connected and enclosed by combustible construction if classified as Group R-2, the separation and openness provided between the Group R-3 buildings with 1 -hour exterior walls and a noncombustible exterior stairway should be considered to maintain the level of safety anticipated with the provisions of IBC Section 503.1.2. EXTERIOR PROJECTION In order to limit the potential for lateral fire spread between buildings, the code regulates projections extending from a building. Section 704.2 permits projections to extend (1) one-third the distance to the lot line where protected openings are required, or (2) up to twelve inches into areas where openings are prohibited. Based on Footnote C to IBC Table 704.8, unprotected openings are permitted with a fire separation distance of more than 3 feet at the Sunset Project. Therefore, where the exterior stairway element between the buildings is attached to only one building, it may be considered as a projection of that building. In accordance with the provisions of IBC Section 704.2, it is permitted to extend up to 12 inches into the area where openings are prohibited. Based on a 3 -foot fire separation distance where openings are prohibited, and assuming the imaginary property line between the two buildings is located nearly at the SUNSET 100 LP SUNSET PROJECT - EDMONDS EXTERIOR STAIR CONDITION Page 3 March 24, 2009 face of the adjacent building, the stairway should be permitted to extend up to 2 feet from the face of the adjacent building. As illustrated in Figure 1 below, the 3 -foot — 6 -inch wide exterior stair shown in the October 7, 2008 architectural plans by R. Corbett Architects and 2 -foot minimum separation distance prescribed by code to the assumed property line can be accommodated in the 6 -foot separation distance between the buildings. r t Nr FIGURE 1: SUBJECT GROUP R-3 BUILDING (RED) WITH PROJECTING EXTERIOR STAIRWAY (GREEN) WITH MINIMUM 2 FEET SEPARATION TO ASSUMED PROPERTY LINE AT ADJACENT BUILDING (BLUE) SUNSET 100 LP SUNSET PROJECT — EDMONDS EXTERIOR STAIR CONDITION PEDESTRIAN WALKWAY Page 4 March 24, 2009 While code provisions for projections generally seek to maintain a space between elements extending from one building toward a separate building, IBC Section 3104 describes conditions for which a pedestrian walkway is permitted to link separate buildings. Figure 2 below illustrates how the upper landing of the stair can link both upper dwelling units to the supplemental stair, functioning as a pedestrian walkway. �z:� Z -.� l Ic w a O'� � f. . . , rUJ o FIGURE 2: GROUP R-3 BUILDING (RED) WITH PEDESTRIAN WALKWAY (GREEN) THAT ALSO SERVES SEPARATE ADJACENT BUILDING (BLUE) SUNSET 100 LP SUNSET PROJECT - EDMONDS EXTERIOR STAIR CONDITION Page 5 March 24, 2009 In order to maintain the degree of separation desired with the Sunset Project, while the exterior stair may be connected to one building, structural connection to both buildings must be avoided as described in Exception 2 to IBC Section 3104.2. As the Sunset Project residential buildings are of combustible construction, Exception 1 to IBC Section 3104.3 would permit the pedestrian walkway to also be of combustible construction. With this project, noncombustible construction is proposed for the exterior element, such that the level of safety provided is in excess of that prescribed by code. Exception 3 to Section 3104.5 does not require fire -resistance rated exterior walls where the buildings are on the same lot in accordance with IBC Section 503.1.2. Section 503.1.2 permits such buildings to be regulated as separate buildings or as portions of one building. As described in the Building Area section above, the aggregate area of the two subject buildings at the Sunset Project are within the allowable area limitations of the code. However, this project identifies an assumed property line between the buildings, and each building is regulated as a separate building in accordance with Section 503.1.2. While the applicable exception to Section 3104.5 does not require a fire -resistance rating, as these buildings are regulated as separate buildings, the exterior walls are fire - resistance rated and exterior openings are limited based on the proximity to the assumed property line in accordance with IBC Section 704.3. It can be noted in Figure 2 that opposing doors accessing the common exterior pedestrian walkway are offset in accordance with IBC Section 704.8. CONCLUSION The Sunset Project in Edmonds consists of three Group R-3 buildings atop a common garage element, in accordance with Section 509.2 of the IBC. The physical separation of the buildings, fire -resistive construction of the exterior walls, and limited openings of the exterior walls, contribute to an inherent level of fire safety between the buildings. Each Group R-3 building contains no more than 2 dwelling units and is protected throughout by approved automatic sprinkler protection. In addition to the subject exterior stairway located between the buildings, the dwelling units are provided with another exit to the east in accordance with Item 2 of IBC Section 1019.2. Based on the construction and occupancy of the Sunset Project, where connected to one building, the subject exterior stairway located between two buildings as identified on design plans dated October 7, 2008 should be considered to comply with the limitations for projections in accordance with IBC Section 704.2 as illustrated in Figure 1 above. SUNSET 100 LP SUNSET PROJECT - EDMONDS EXTERIOR STAIR CONDITION Page 6 March 24, 2009 When this exterior stair element is expanded to serve two buildings, the upper landing and exterior stairway should satisfy the provisions of IBC Section 3104 as a pedestrian walkway, as described with Figure 2 above. Feel free to contact me, or to have Ms. Ann Bullis, City of Edmonds Building Official contact me directly, at 425.745.4700 or by e-mail at BrianT@AegisEngineering.com with any questions or for clarification of the information presented in this document. Since Brian C. Thompson; cc: Collin Madden / cmadden@triliadcapital.com R. Brian Corbett / r—brian@msn.com AEGIS E61EERIN Brian C. Thompson, P.E. 6725 162nd Pl W Lynnwood, WA 98037 www.AegisEngineering.com (425) 745-4700 fax (206) 801-5797 Summary Brian Thompson, the Principal of Aegis Engineering, is a registered professional engineer in Washington, Oregon and California. He holds a Master's Degree in Fire Protection Engineering from Worcester Polytechnic Institute and has project experience involving high-rise buildings, health care facilities, historic rehabilitation, mixed-use and industrial occupancies. Experience Education Affiliations Mr. Thompson entered the fire protection field over 15 years ago, and is familiar with the application of current engineering models and methodologies to evaluate unique project conditions, including complex analysis of the anticipated performance of fire protection and smoke control systems. His project responsibilities include developing design strategies for project fire protection and building code approaches, evaluation of design plans for code compliance, as well as system inspection and testing. Other fire protection engineering experience has been gained by Mr. Thompson through previous employment in Chicago and San Francisco. Other applicable experience includes firefighting, civil engineering work, site master planning, and forensic investigations. Brigade Complex, Fort Lewis, WA City Heights, Ferndale, WA Emerald Queen Casino Fife, WA Microsoft Office Buildings, Redmond, WA Olympic BioFuels Facility, Poulsbo, WA Plaza Center, Bellevue, WA Group Health Cooperative, Providence Cancer Center, Seattle, WA Everett, WA US Green Building Council, Berkeley, CA LEED-NC Technical Review (2005) Worcester Polytechnic Institute, Worcester, MA M.S., Fire Protection Engineering (2003) Marquette University, Milwaukee, WI B.S., Civil Engineering (2000) Snoqualmie Casino Snoqualmie, WA UW Medical Center Seattle, WA Vancouver Clinic Vancouver, WA Wells Fargo Plaza, Tacoma, WA Protection Knowledge Concepts, Chicago, IL Automatic Sprinkler System Design and Water System Analysis (1998) • International Code Council (ICC), WA Fire Code Technical Advisory Group • National Fire Protection Association (NFPA), AEBO Section • Salamander Honorary Fire Protection Engineering Society, Gamma Chapter • Society of Fire Protection Engineers (SFPE), Pacific Northwest Chapter Fire Protection • Building Code Consult • Design • Engineer foe. 1890 CITY OF EDMONDS 121 STH AVENUE NORTH • EDMONDS, WA 98020 • (425) 771-0220 • FAX (425) 771-0221 Website: wwN.ci.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning • Building • Engineering April 2, 2009 John Thoresen Sunset 100, LP 1611872 d Ave W Edmonds, WA 98026 RE: Request for Building Code Interpretation 121, 123, 125 Sunset Ave N. Dear Mr. Thoresen, GARY HAAKENSON MAYOR This letter is in response to the report by Brian C. Thompson, PE of Aegis Engineering dated March 24, 2009 that Collin Madden submitted requesting that the proposed exterior stairway landings between buildings be considered pedestrian walkways in accordance with Section 3104 of the International Building Code. We have read the report and have determined that the engineer has adequately justified that the proposed exterior stairway landing areas between buildings can be considered pedestrian walkways as set forth IBC 3104 to address fire separation issues, however we need further clarification from the engineer regarding the following items: • Location of Proposed Stairways/Landin)xs: Clarify in the request the specific locations of the exterior stairway(s) and landing(s). Will it be between 121 Sunset N and 123 Sunset N, and/or between 123 Sunset N and 125 Sunset N? • Type B Dwelling Units: The first paragraph of Page 5 of the report states that, "In order to maintain the degree of separation desired with the Sunset Project, while the exterior stair may be connected to one building, structural connection to both buildings must be avoided as described in Exception 2 to IBC" Section 3104.2. " This exception states "For the purposes of calculating the number of Type B units required by Chapter 11, structurally connected buildings and buildings with multiple wings shall be considered one structure. " Please clarify if it is the engineer's intent of this paragraph in his report to not provide Type B dwelling units in these buildings. We caution you on the use of this exception as an exemption for providing Type B dwelling units. Compliance to the provisions of the 2006 International Building Code should not be taken as an indication of compliance with federal or Incorporated August 11, 1890 Sister City - Hekinan, Japan statutory requirements, including compliance to the Fair Housing Accessibility Guidelines. The two documents are separate and independent. We suggest that you consult with your legal counsel regarding the compliance of this plan with the Fair Housing Act amendments and the Americans with Disabilities Act. The design raises significant issues regarding compliance with these federal statutes and City approval of plans under the IBC and State building code is not an indication that the design complies with the requirements of these federal statues. • Plan/Details:. Provide plans and construction details showing how the requirements of Exception 2 of IBC 3104.2 will be met. Should you have any questions, please feel free to contact me at 425-771-0220. Sincerely, *JA. _- Ann Bullis, CBO Building Official Corbett Architects P.S. Inc. 1951 31st Avenue West, Seattle Washington, 98199 April 7, 2009 City of Edmonds Development Services Department Attn:Ann Bullis, Building Official. Proiect Sunset 100, LP. Mixed use DEVELOPMENT SERVICES COUNTER The following letter is in response to your letter dated April 2, 2009 for the project located at 121,123,125 Sunset Avenue North. 1) The proposed shared pedestrian walkway landing and stairway is to be located between the north and middle buildings. 2) The landing will be a self supported structure on four steel tubes with the stair stringers spanning fromfrom the landing to the ground. There will not be any attachment to either building. We do understand that your approval does not determine compliance with federal fair housing .act and appreciate your bringing this matter to our attention 3) As per earlier building department requests, we will be providing shop drawings for the pre -fabricated stairs and the predestrian walkway landing. Should you have any additional questions or comments please feel free to contact me through e-mail at brian corbettarchitects.com or by phone at (206) 283-7808. Best regards, R. Brian Corbett Corbett Architects PS Inc. CORBETT ARCHITECTS P.S. INC. 1951 31ST AVENUE WEST SEATTLE WASHINGTON 98199 206.2837808