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Home My WebLink AboutSebastian Review Comments 8 17 2010 �I, �� 13831 Narfhwest Freeway Suite 330 Hpuston.TX 7?040-5215 USA ROLF JENSEN&AS50CIATES,INC. www.rjainc.com FIRE PRC?TECTIC}N C{3NSULTANTS +l 713-462-1840 Fax�+1 713-�162-0$12 August 13, 2010 VIA ELECTRONIC MAIL: mrudolf@timbersresorts.com Mr. Mark Rudolf, AIA Timbers Resorts 201 Main Street Carbondale, CO 81623 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS SEBASTIAN HOTEL, VAIL COLORADO Dear Mr. Rudolf: Rolf Jensen & Associates, Inc. (RJA) has been involved in many facets of the fire protection systems at the Vail Plaza Hotel (now the Sebastian), located at 16 Vail Road in Vail, Colorado. RJA was contracted to review the smoke control system design drawings and prepare a Smoke Control System Summary report for the architect, Zehren and Associates, on May 30, 2006. RJA was subsequently engaged to act as the special inspector for the commissioning of the smoke control systems at this facility. RJA submitted a special inspection and commissioning report for approval by the Town of Vail dated July 31, 2008. We understand that new ownership is planning on architectural changes to the lobby atrium. This atrium is referred to as as Atrium A in previous documents issued by RJA. The architectural changes to the atrium involve opening the rear portion of the atrium to accessory spaces without installing rated separation. The simplest means to accomplish this is to redefine the atrium boundaries. This will require changes to the existing smoke control system components and sequence of operations. RJA has been requested to review the proposed changes and indicate how the new atrium can meet the requirements of current code. Specifically, RJA has been asked to provide documentation on how the existing smoke control system will be modified. The following letter outlines how the existing system can meet the separation and smoke control requirements for the new Atrium A with slight modifications. The Sebastian was originally designed and constructed under the 2003 edition of the International Building Code (IBC), as adopted by the Town of Vail (TOV). Currently, the TOV has adopted the 2009 edition of the IBC. RJA's review of the changes to the atrium and the requirements for smoke control will be to the 2009 IBC. O 2010 Rolf Jensen&Associates,Inc.All Rights Reserved S �� ■ ■ ■� �� .�� MR. MARK RUDOLF H50136 — Page 2 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 EXISTING SEBASTIAN The Sebastian consists of two 9-story high-rise condominium and guest room towers with two levels of parking garage below grade. The facility features hotel and condominium residential units with accessory use spaces including conference rooms, ballrooms, restaurants, retail, exercise, office spaces and loading docks. The Fire Command Center for the facility is located at the Upper Level (UL) level at the northwest corner of Building B. This location is large enough to accommodate all of the panels and controls for the facility. There are two atriums within the building, Atrium A and Atrium B, with independent smoke control systems. Currently, Atrium A is programmatically divided into two spaces by a fireplace and pedestrian bridge (see Figure 1 below). The front portion of this atrium is four stories high and includes the guest lobby and front desk. The rear portion of the atrium includes a guest seating area adjacent to a fireplace and is open to one story (160 Level) and an open pedestrian walkway on Level 170 that divides the front and rear portions of the atrium (see Figure 2 and Figure 3). Rolling fire shutters on the rear portion of the bridge close upon atrium fire alarm activation. The atrium is separated from all other areas of the building by 1-hourfire rated construction and 45-minute opening protection. Windows in the atrium boundary are intended to be protected with closely spaced sprinklers. �o i LI �� r� �� i�- � - -_—��- - �` �.9•�s,:+� Open Y '�� `' � � � To , � t`� � r;�, � - s� � • Above �-� -- ,— 1' �. � ;, i �`; i + i { 1 Make Up Air Locations 4 iG1Y�f,••�� _. � `y�.,�. � L_: YJ � �� 5 . �"�/// ' �i .. � �.—�! 'f/ /.b:�� r ��l �fl � � •� � i �_ `f _ Figure 1 —Current Atrium A Boundary at 160 Level � ,.JL��`�,�I � - , r � ` U] ' � �J� � � — �-� � � I ` �y Open � To Location of 1 � Rolling Fire Shutters � � Below � � I r i � t � — — ___ _ 1- . " �� Pedestri In Bridge - �� Figure 2—Current Atrium A Boundary at 170 Level MR. MARK RUDOLF H50136 — Page 3 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 Exhaust Locations ♦ ♦` 170��\ Bridge and Fire Shutter Make Up Air__ __i Through Main Lobby Doors 160 Level Figure 3—Section of Current Atrium A EXISTING SMOKE CONTROL SYSTEM DESCRIPTION The building's fire alarm system is used to control, monitor and activate the mechanical smoke control systems. The mechanical smoke control system was installed based upon approved plans. The concept for smoke control for this facility involves active protection based on the exhaust method described in NFPA 92B, and is provided for both Atriums, one in each tower. These atriums are designated on approved plans and within this report as Atriums A and B. Each atrium smoke control system is designed to initiate and operate independently. Currently, five fans provide exhaust for Atrium A. Four intake louvers leading to four roof mounted fans, each providing 16,250 CFM of exhaust, are located in the four corners of the four story high portion on the front side of the atrium. An additional 11,300 CFM exhaust fan is located in the ceiling on the rear side of the atrium. The total exhaust provided is currently 76,300 CFM. A total of 16,000 CFM, (two 8,000 CFM fans), is provided mechanically to make up some of the air exhausted from Atrium A. The remainder of make up air is provided through actuated doors to the exterior. Upon activation of any area or beam smoke detectors located in Atrium A, or upon activation of any sprinkler in the atrium, the following occurs: • Doors #313, #334 and #331 open to provide additional supply/make-up air; • All doors between the atrium and adjacent areas normally held open close; • Both rolling fire doors (located on Bridge 465) close to provide separation of the pedestrian bridge; • Normal HVAC system shutdown; • Smoke Exhaust Fans SEF-5A1 (located on the rear side of the lobby at Level 180 Roof), SEF-7A1, SEF-7A2, SEF-7A3 and SEF-7A4 (located at level 200) activate; • Supply Air Fans SF-4A1 and SF-4A2 (located on Level 170) activate. MR. MARK RUDOLF H50136 – Page 4 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 CHANGES TO ATRIUM A BOUNDARIES The boundaries of Atrium A will be changed to separate the front and rear sides of the space. The separation will be accomplished by relocating the existing bridge rolling fire shutters from the rear to the front side of the bridge at the 170 Level. In addition, a new Won door will be installed below the bridge on the front side at Level 160. See Figure 4, Figure 5, and Figure 6 for the new boundary locations for Atrium A. In addition, the existing revolving doors will be replaced with a pair of swinging doors with a vestibule. By making the rear portion of the existing atrium open to only two levels, a protected opening is no longer required for that space per IBC Section 708.2(7). ��° :� � �� Location of New � � � � Won Door � �� i:�1 � f o � � . -- lsa.°'i:��. �• .. ,:ti Open r. . ' j To ' � ...L:.L� Above �� „ K . . .E♦. .� . 1 . ;� � F _��,�,,,j,� Make Up Air Locations 'i.%r, •�' � � � � � . u n � � �!�`, � - � ,�- , � � E r� � ,�'�� • I . I. r-; i ir� �h ,.:.. �:� i� � �..-' Figure 4–New Atrium A Boundary at 160 Level �� New Location of � � Shutters f+r — - `� ��_� � � � { � Open „ f To � �, � Below ,. 1 � _ , � � _� � � ��=�I C� � Bridge - — Figure 5–New Atrium A Boundary at 170 Level MR. MARK RUDOLF H50136 - Page 5 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 Exhaust Locations � �� Fire Shutter And Won Door �17�e�gridge Make Up Air__ __i Through Main Lobby Doors 160 Level Figure 6—Section of New Atrium A CHANGES TO ATRIUM A SMOKE CONTROL SYSTEM The new boundaries of the atrium will require the existing smoke control system to be modified. In accordance with Section 909.8.1 in the 2009 IBC, a smoke control system designed using the exhaust method must maintain the smoke layer at least 6-feet above the highest surface that is a portion of the means of egress system. With fire shutters closing off the bridge from the atrium, Level 160 is the highest surFace forming a portion of the egress system within Atrium A. Based on calculations outlined in NFPA 92B for an axisymmetric 5,000 BTU/second fire located on Level 160, the required exhaust is approximately 24,000 CFM (see calculation attached). Therefore, two of the four existing smoke control fans will be decommissioned. The two remaining fans will each provide approximately 16,250 CFM exhaust each, for a total of 32,500 CFM of exhaust provided for Atrium A. Make up air will be provided by both mechanical and natural means. The two existing fans providing 8,000 CFM supply each will remain. In place of the current revolving door into the lobby, a vestibule with a new pair of 3-ft by 9-ft doors (54 sqft) will be added. These new doors will be in addition to the two 3-ft by 7-ft doors (42 sqft) currently installed opening to the exterior. All of these doors will open to provide natural make up air for Atrium A upon activation of the smoke control system. Table 1 is a summary of the exhaust and make up air for the new Atrium A. Table 2 is a summary of the required and available make up air flow rates. Table 1 — Required and Provided Exhaust for Atrium A. Exhaust CFM Equipment Required Provided SEF 1 16,250 SEF 2 16,250 Total 23,190 CFM 32,500 CFM MR. MARK RUDOLF H50136 - Page 6 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 Table 2— Required and Available Make Up Air for Atrium A. Make Up Air CFM Equi ment Re uired* Available SF 1 8,000 SF 2 8,000 Door 3'x7' 4,200 ** Door 3'x7' 4,200 ** Door 3'x9' 5,400 ** Door 3'x9' 5,400 ** Total 29,250CFM 35,200 CFM *-Required make up air based on providing a minimum of 90%of the total exhaust provided **-Available airflow through doors based on limiting velocity to 200 feet per minute through the opening As seen in Table 2, the available make up air is more than 100% of the exhaust to be provided with estimated airflow velocities through doors less than the maximum allowable 200 fpm. Since makeup air typically accounts for 90% of exhaust flow rate, due to leakage, the available makeup air provided by doors could be reduced from 96 sqft to 66.25 sqft and still meets the maximum 200 fpm speed limit. The following is the new sequence of operations based on activation of smoke or beam detectors, or upon activation of any sprinkler located in Atrium A: • All 6 front lobby doors, including two sets of double doors located in the new vestibule open to provide additional supply/make-up air; • All doors between the atrium and adjacent areas normally held open close; • Rolling fire doors and a single Won door (located on and below Bridge 465 respectively) close to provide separation of the walkway and rear side of the lobby space (formerly part of the atrium); • Normal HVAC system shutdown; • Fireplace gas supply and exhaust fan shutdown • Two Smoke Exhaust Fans (two of either SEF-7A1, SEF-7A2, SEF-7A3, SEF-7A4 — to be coordinated with a mechanical engineer) located at Level 200 activate; • Supply Air Fans SF-4A1 and SF-4A2 (located on Level 170) activate. Following discussion with the TOV, the following special condition will be placed on the activation of the smoke control system: • Upon activation of the dry sprinkler system located just outside the Atrium A Lobby (porte cochere), the smoke control system in Atrium A will NOT automatically activate. If the FACP receives an atrium waterFlow of smoke alarm signal subsequent to a waterflow alarm signal from the porte cochere system, it will be reported as a fire alarm signal, but will not initiate the smoke control sequence. This will minimize the chance that a fire event in the porte cochere could be further exacerbated by pulling products of combustion into the building. Manual operation of the Atrium A smoke control system will be maintained. MR. MARK RUDOLF H50136 — Page 7 ATRIUM A SMOKE CONTROL SYSTEM RENOVATIONS June 30, 2010 SEBASTIAN HOTEL - VAIL, COLORADO Revised August 13, 2010 With the rear side of the space now outside of Atrium A, the following changes to the smoke control system will occur: • SEF-5A1 (located on the rear side of the lobby at Level 180 Roof) will be decommissioned; • Sliding Door#313 will no longer open as part of the make up air system; • Any doors previously held open and part of the previous atrium boundary are no longer required to close; • Smoke detectors and sprinkler waterflow switches located on the rear side of the space and on/below the bridge will be reprogrammed out of the smoke control sequence so that activation does not initiate the Atrium A system. In conclusion, the proposed modifications to Atrium A result in changes to the existing smoke control system. The required exhaust for the new Atrium A is less than that currently provided, therefore, several existing smoke exhaust fans will be decommissioned. The two existing doors to the outside, two additional doors to the outside, and two 8,000 CFM fans will provide more than adequate makeup air for the smoke control system. The smoke control sequence at the main fire alarm control panel will be reprogrammed. A new smoke control panel graphic will be provided. A new operational smoke control matrix will be coordinated with the design team, contractors and ownership and provided for review by the Town of Vail. Please let us know if you have any questions or concerns regarding this report. Sincerely, ROLF JENSEN & ASSOCIATES, INC. 4p'p�?•��G'�',!, Prepared by: Reviewed by: a-'''S.00 • G�',C? ` �� '� �.cr�, g•[3•�0 :�� • � �;•. •'C? S��NA�F.� J hn H. Mammoser, P.E. �i�> Sean S. Donohue, P.E. �co, �a, M-r,Tx� JHM/SSD/alf H50136/VPH Sebastian LT Smoke Control System rev 8-13-10 Encl.: NFPA 92B Calculations c: Michael McGee, Deputy Fire Marshal, Vail Fire & Emergency Services Martin Haeberle, Building Official, Town of Vail Mark Norris, Timbers Resorts Gary Ross, Timbers Resorts Scott Parks, Vail Plaza Hotel