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Ombu Salon AM&M.pdfCITY OF EDMONDS 121 51" Avenue North Edmonds, WA 98020 DEVELOPMENT SERVICES DEPARTMENT Building • Engineering • Planning Website: www.edmondswa.gov January 2, 2018 Heidi Helgeson H2D Architecture Re: Alternate Design Request for use of basement for commercial use at Ombu Salon 121 3rd Ave N Permit: BLD2018-1021 Dave Earling Mayor PHONE: 425.771.0220 Fax: 425.771.0221 As per your request dated December 4, 2018: "We are requesting the use of the basement for office, laundry, storage and employee break room at the Ombu Salon permit #BLD20181021 per the alternate Design and Methods section from IBC 2015 104.11. The basement would not be allowed for customer use. The existing ceiling height of approximately 6"-10" in the basement does not meet the means of egress code requirement of 7'-6" for ceiling height. Although the ceiling height does not meet the letter of the code, we would like to propose the use of the basement for the purposed listed above and based on the below listed code sections and compliance." Please see the entire proposal attached at the end of this document. Although the substance and intent of the proposal are clear, it should be noted that not all code references and conclusions made within the proposal are necessarily accurate or agreed with. City response: We acknowledge your request and recognize your proposal as utilizing the Work Area Method of the 2015 International Existing Building Code (IEBC) by which to justify the proposal. Be aware that this method is the compliance approach to be applied not just to the basement, but to the entire existing building as required by IEBC 301.1. There are actually two issues in which the existing building does not conform to the required code standards. 1. The basement ceiling height, as measured by the city building inspector (and as documented on the energy code forms for lighting), is actually 6'-9" finished, nine inches shy of the 7'-6" minimum required by IBC 1003.2. 2. The riser heights within the stairs to the basement are 7% inches, exceeding the maximum height of 7 inches allowed by IBC 1011.5.2. Ceiling height It is unlikely that the ceiling height ever complied with code standards for single family residential construction. However, several factors lend support to allowing the space to be used as proposed. The building itself appears to be otherwise generally compliant with residential code requirements prior to the current change of occupancy project, and has been designed to comply with the applicable requirements for the proposed used as a commercial building. The new use has been evaluated for compliance within the hazard risk categories for Means of Egress, Heights and Areas and Exposure of Exterior Walls, as required by the IEBC. The proposal indicates the basement will not be used by the public, in which case it will be limited to employees, who will likely become accustomed to the short ceiling height, and not find it to be a hazard or deterrent to normal egress from the space. The small size of the building, the small occupant load and the short travel distance to the front exit door also contribute to relative safety of the occupants of the basement. The voluntary upgrade of exterior walls to one hour construction, although not within the category of means of egress, also improves the overall safety of the building occupants. Along with these factors, it is also recognized by the building official that the existing ceiling height does not constitute a distinct hazard to life, thus the basement is hereby approved for use as proposed. Stair riser height IEBC section 1012.4.2 states "When a change of occupancy classification is made to an equal or lesser hazard category as shown in Table 1012.4, existing elements of means of egress shall comply with the requirements of section 905 for the new occupancy classification." Section 905 defers to section 805 which states in exception 2 to section 805.4.4.1 "Means of egress conforming to the requirements of the building code under which the building was constructed shall be considered compliant means of egress if, in the opinion of the building official, they do not constitute a distinct hazard to life." Since the stair risers were obviously in compliance with the standards of the International Residential Code prior to the current change of occupancy project, and exceed the maximum allowed height by only inch, it is determined that they do not constitute a distinct hazard to life, and are hereby approved for continued use at the existing height. Thank you, r Leif Bjor ack Building Official City of Edmonds (425) 771-0220 Cc: Beth Sanger File December 4, 2018 Attn: Leif Bjorback City of Edmonds 121 511, Ave N Edmonds, WA 98020 architecture design We are requesting the use of the basement for office, laundry, storage and employee break room at the Ombu Salon permit #BLD20181021 per the Alternate Design and Methods section from IBC 2015 104.11. The basement would not be allowed for customer use. The existing ceiling height of approximately 6'-10" in the basement does not meet the means of egress code requirement of 7'6" for ceiling height. Although, the ceiling height does not meet the letter of the code, we would like to propose the use of the basement for the purposed listed above and based on the below listed code sections and compliance. 1. The building meets the requirements for height and area for the proposed occupancies of B at the main floor and B in the basement. -IBC Table 504.3 Building height — based on this table the building is in conformance for building height for occupancy of B. -IBC Table 504.4 Number of stories above the grade plane — based on this table the building is in conformance for the proposed occupancies of B. -IBC Table 506.2 Area allowed — based on this table the building is in conformance for the proposed occupancy of B. 2. The building permit issued for the project has a requirement to install the required 1 hour fire resistance rating for the existing walls which are between 5'-10' from the property line. The existing basement would fall into a portion of the building located between 5'40' from the property line. The exterior walls would not need to be rated based on the equal hazard class IEBC 1012.62. We will continue forward with the plan to fire rate the walls to offset the lack of compliance for the riser height on the existing stair (see #6 below). -IBC Table 602 Fire resistance rating for exterior walls —the issued building permit is proposed to install the required 1-hour fire resistance rating for the exterior walls for areas between T-10' from the property line which will meet the requirement for the basement use of B. IEBC 1012.6.2 equal hazard class for existing walls will override the IBC requirement and thus the fire rated walls would not be required. 3. The existing basement does not meet the means of egress requirement for ceiling height. -IBC 1003.2 Ceiling height is required to be TV for means of egress. The existing basement does not meet this requirement. -IEBC 704.1 Alterations shall be done in a manner to maintain the level of protection provided for means of egress. -IEBC 803: No vertical openings other than the stair proposed. Interior wall finish will be '/z" painted gypsum wall board to comply with the IBC for interior finishes. The stair will be equipped with handrails at guardrail at the main floor level as proposed in the approved permit. -IEBC 804: Exits are not serving an occupant load greater than 30 occupants. -IEBC 805.2.2 Means of egress conforming to the requirements of the building code under which the building was construction shall be considered compliant means of egress if, in the opinion of the code official they do not constitute a distinct hazard to life. With the change of use, the hazard class will be deemed equal between the existing R-3 and B occupancy. The means of egress is not proposed to be more unsafe than the existing condition. All other aspects, other than the ceiling height at the basement, meet the current building code and do not R EVis ioN 23020 Edmonds WcU, -113, Edmonds, WA 98020 1 p. 20E3.54Z3734 I e, hedGh2darchitects.carn I w. h2darchilects.com kw a�a v c LiP20/ f —/oLl create a distinct or greater hazard to life. Means of egress lighting and exit signs will be installed to comply with IEBC 805.7, IEBC 805.8, IEBC 905.2 and IEBC 905.3. -IEBC 805.3 Exiting requirements are met with the information above. -IEBC 1005 Shall comply with Section 1012 as noted below in #4. 4. The occupant load and maximum distance to the exits meets the current code requirements if the basement is converted to a B occupancy. The existing basement for `business areas' occupancy is 681 sf/100 gross = 6.8 or 7 occupants. The combined occupant load (for main floor and basement) at front exit door will be 29 occupants, which meets the requirements for one exit Maximum distance of common path of egress travel distance from furthest point at lower floor to main floor front exit door is 70' which meets the below listcd requirements. -IBC Table 1004.1.2 Maximum floor area allowance per occupant for business is 100 gross. -IBC Table 1006.2.1 Maximum occupant load of space with one exit, B=49. Maximum common path of egress travel distance without sprinkler system for occupant load over 30 occupants is B=75'. -IBC 1006.3.2 (2) Stories with access to one exit: B = 49 occ, 75' travel distance -IBC Table 1006.3 Path of egress travel to an exit shall not pass through more than one adjacent story. (Meets this requirement) -IBC 906.1 Portable fire extinguishers shall be installed. 5. Change of use to convert the existing single family to a B occupancy meets the requirements. Height and area hazard category for R-3 and B are equal at #4. As noted in #1 above, the height and areas comply. -IEBC1012.4.2 Means of egress for change of use to equal hazard category. Existing elements of means of egress shall comply with the requirements of Section 905 for the new occupancy classification. See #3 above. -IEBC Table 1012.5 Heights and Areas hazard category. R 3 and B area equal #4. -IEBC 1012.5.2 Height and area for change to equal hazard category. The height and area of the existing building are deemed acceptable. 6. Existing stairway, 39-1/4" in width, is currently not enclosed, but would be in compliance with width requirements. The existing risers are not in compliance at 7-1/4" tall and the existing treads are in compliance at 11-1 /47. The ceiling height at the stair meets the required head height of 80" above the finish nosing and is in compliance. To bring the stair risers into compliance would be a financial hardship on the Owner. In order to bring the stair riser into compliance, the following work would need to be performed: structural modification to the floor system to allow for a long stair run to meet the rise/tun, relocating the hallway wall at the lower floor to maintain the required 3' clearance, and installing new finishes (drywall, trim, flooring, lighting, and paint) due to the work of modifying the stair and hallway wall. -IBC 1019.3.1 Exit access stair that serve only two stories are not required to be enclosed. -IEBC Table 1012.4 B and R3 are equal means of egress hazard category #4. -IEBC 2015 1012.4.2 Means of egress for change of use to equal or lower hazard category indicates that the existing stair would need to be brought up to current compliance for the stair run. -Basement to comply with IEBC 905 (Lighting and existing signs) and 805. 7. Ventilation would need to meet IMC 2015 403.3 mechanical ventilation requirements. The ventilation for the basement would be part of the system serving the other areas of the building. Each space would be provided ventilation based on the individual requirements. IMC Table 403.3.1.1: Minimum ventilation rates for various occupancy classifications. 8. Energy code requirements -WSEC Table C402.1.3: Basement walls to be minimum of R-21. WSEC C503.1.3 Existing ceiling, wall or floor cavities exposed during construction provided that these cavities are insulated to full depth with insulation having a min nominal value of R-3.0/inch. -Heating and cooling system in basement to comply with WSEC C403. 23020 Edmonds Way, -113, Edmonds, WA 98020 1 p. 206.542.3734 1 e. heidCh2darchitects.eom I w. h2darchitects.com As noted above, the existing low ceiling height at the basement does not meet the letter of the code, but the intent for the use of the existing space does not create a more hazardous Condit ion. To increase the safety of the building, the exterior walls will be converted to a I hour fire rating, although this requirement would not be necessary for the existing building use. I can be reached at 206-542-3734 or at licidi@h2darchitects.coni with any further questions. Regards, Heidi Helgeson Principal H2D Architecture + Design 23020 Edmonds WcU, -113, Edmonds, WA 9"0 1 p. Wo.542.3734 1 e. I w. h2ckrd*Ieds.com