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HomeMy WebLinkAboutMcGough on WCC Elevator Smoke-Control McGough Five Generations Building Confidence TO: Mr.Lyle Oman,Building Official, City of Orono CITY OF ORONO , FROM: Tate Halvorson,QA BUNLDING T PLAN REVIEW NNaPECl OA CC: David Kulich,Project Architect,Miller Dunwiddie Architecture DATE- —J7 d -- ERM T NO. ?':iit 0FSS Paul Egertson,Project Manager,McGough '• ' SJL','!rTED Dave Krings, State Building Codes and Standards Division C t r'IT` %rt.: \'."!H`!CORRECTIONS AS NOTED Gerry Norman, State Building Codes and Standards Division CUECT&RESUBMIT r,,- , . a i.... ,�`i�,n. ,'G ,k shai be dons DATE: May9 2005 ? �� r zon code. C . F ey.r: i .s. a ly n ed in tills review. KEEP THIS PLAN SET ON$1TE AT ALL TIMES RE: Wayzata Country Club Elevator Smoke-Control Based on your desire to have a State opinion on the issue of smoke control for the Wayzata Country Club's elevators and with the approval of our Architect, I called Dave Krings Monday morning. Dave called me back immediately and very graciously agreed to meet with me in the afternoon. He asked Gerry Norman if he could attend and we all met at 2:00! We discussed the status of the next code adoption cycle and the possible changes to the codes through amendments to the 2003 IBC. Gerry indicated that he is on the committee working on these amendments and the committee has recommended the deletion of the amendment,IBC 707.7. As you know this amendment has, in effect,overridden the provisions of IBC 707.14 which allows the elimination of elevator lobbies and smoke control for low-rise elevators. Gerry indicated that it is highly likely that the committee's recommendation will be upheld but it is not a certainty. There are pending amendments to the 2006 IBC that will be voted on at the ICC Annual Business Meeting(ABM)in September that may affect the final outcome. Additionally,proponents for the present amendment,especially manufacturers of products that achieve the smoke control for elevators,may be successful in seeking a public hearing,during the adoption process,and have this amendment retained. One concern of many Building Officials, including myself,is that the final code adoption should address the issue of smoke control for elevators in buildings with five or more stories even if rated corridors are not required. We discussed the specifics of the Wayzata Country Club while looking at the floor plans and I indicated our desire to eliminate some or all of the"Smokeguard"systems on the elevator openings based on the above possible code changes and the limited nature of any"stack effect"in a low-rise structure such as the Country Club. I also discussed the possibility of providing smoke gaskets on doors adjacent to the elevators area to provide lobbies or lobby"areas". Both Dave and Gerry were reluctant to endorse this approach given the present codes and the uncertainty of changes. However,upon further discussion some other options did develop. I will note,separately,the options that were developed. Elevator A: Elevator A is the elevator being added in the existing building. It travels from ground floor level through the 1st floor to the small 2"floor office area. The travel is less than 25 feet. It was noted that the 1st and 2nd floors are open to each other via both an adjacent open stair and a large floor opening and it was agreed that it did not make much sense,since smoke and hot gas from a fire rises,to worry about any smoke developed on the 151 or 2"d. Since the elevator at the ground floor level is adjacent to mechanical and storage rooms,both Dave and Gerry were comfortable with supporting the idea of providing smoke-and draft-control at the lowest,most critical level. Since Wayzata Country Club has requested an additional door be added to close off this area on the ground floor level,visually,from the other areas, it is our proposal that we construct this area as an elevator lobby. All the adjacent rooms are sprinklered and have been constructed to resist the passage of smoke per 2737 FAIRVIEW AVENUE NORTH S 1'. PAW.:. MINN1:r:SO'1 A 55113-1372 PHONE: (651) 633-5050 FAX: (651) 633-5673 0 McGough Jive Generalions Building, Confidence the requirements of incidental uses.The doors are all 1-3/4 inch solid-core doors and they will be provided with smoke gaskets. 1-3/4 inch doors have traditionally been considered more or less equivalent to 20-minute rated doors and it was pointed out during the meeting that the 2003 IBC has"corrected"the language regarding elevator lobbies by changing the wall requirement from a"fire barrier"wall to a"fire partition"wall. Thus,when the adoption of the 2003 IBC is complete, only a 20-minute door will be required for elevator lobbies regardless of the number of stories. Thus we seek your approval to just construct the described elevator lobby on the lowest level and recognize that the upper two levels,open to each other in this area,can not be effectively separated. Elevator B: Elevator B is the elevator in the new addition that travels from the sub-basement through the ground floor to the 15`floor. The travel is more than 25 feet so an elevator vent has been provided. It was acknowledged that the intent of the smoke-and draft- control provisions for elevators was not necessarily to prevent smoke from entering the elevator shaft but,rather,to prevent smoke from migrating to other floors from the level of development. Therefore, it should be possible to either provide a positive or negative pressure within the elevator shaft to control the movement of smoke. A positive pressure within the shaft could prevent the smoke from entering the shaft and a negative pressure might be utilized in conjunction with an exhaust fan, in lieu of the elevator vent,to send smoke within the shaft out through the top of the shaft to the exterior. Dave and Gerry indicated their concurrence, in principle,of this approach but also noted that it would be up to the AHJ to determine if this was appropriate and what other considerations would be necessary. After consultation with our Mechanical, it was decided that pressurizing the elevator shaft would be the most effective method. If you consider this an acceptable option,the design team will put together a fmal design for your approval. The system will be designed to only operate when one of the local smoke detectors in the adjacent draft curtain detects smoke. It will then pressurize the shaft with a fan sufficient to keep smoke from migrating into the enclosure. The fan will draw outside air for this purpose and the opening into the shaft will be protected by a combination damper. There will be a keyed control for the fire department. If you agree that we may take the approaches noted,we will work with Miller Dunwiddie to put a final design package together as soon as possible. I have copied Dave and Gerry with this memo so they can let you know if I have not correctly interpreted their comments. Thanks much for your assistance in this matter. We look forward to your response. 2737 I•AIRVII W AVENUE NOR t S C. i'AUI.... MINNI:::SO'FA 55113-1372 PIIONF:: (651) 633-5050 I AX: (651) 633-5673 • 0 McGough rive Generations Building Confidence the requirements of incidental uses.The doors are all 1-3/4 inch solid-core doors and they will be provided with smoke gaskets. 1-3/4 inch doors have traditionally been considered more or less equivalent to 20-minute rated doors and it was pointed out during the meeting that the 2003 IBC has"corrected"the language regarding elevator lobbies by changing the wall requirement from a"fire barrier"wall to a"fire partition"wall. Thus,when the adoption of the 2003 IBC is complete, only a 20-minute door will be required for elevator lobbies regardless of the number of stories. Thus we seek your approval to just construct the described elevator lobby on the lowest level and recognize that the upper two levels,open to each other in this area,can not be effectively separated. Elevator B: Elevator B is the elevator in the new addition that travels from the sub-basement through the ground floor to the 1st floor. The travel is more than 25 feet so an elevator vent has been provided. It was acknowledged that the intent of the smoke-and draft- control provisions for elevators was not necessarily to prevent smoke from entering the elevator shaft but,rather,to prevent smoke from migrating to other floors from the level of development. Therefore, it should be possible to either provide a positive or negative pressure within the elevator shaft to control the movement of smoke. A positive pressure within the shaft could prevent the smoke from entering the shaft and a negative pressure might be utilized in conjunction with an exhaust fan, in lieu of the elevator vent,to send smoke within the shaft out through the top of the shaft to the exterior. Dave and Gerry indicated their concurrence, in principle,of this approach but also noted that it would be up to the AHJ to determine if this was appropriate and what other considerations would be necessary. After consultation with our Mechanical,it was decided that pressurizing the elevator shaft would be the most effective method. If you consider this an acceptable option,the design team will put together a final design for your approval. The system will be designed to only operate when one of the local smoke detectors in the adjacent draft curtain detects smoke. It will then pressurize the shaft with a fan sufficient to keep smoke from migrating into the enclosure. The fan will draw outside air for this purpose and the opening into the shaft will be protected by a combination damper. There will be a keyed control for the fire department. If you agree that we may take the approaches noted,we will work with Miller Dunwiddie to put a final design package together as soon as possible. I have copied Dave and Gerry with this memo so they can let you know if I have not correctly interpreted their comments. Thanks much for your assistance in this matter. We look forward to your response. 2737 FAIRVIEW AVI:NUI: NOR III SI'. PAt_I.:_ MINN':SO'I'A c5 I i.3-1.372 PIIONI (651) 633-5050 I'AK: (6511 633-5t,73