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Dawes Hse Complance Alternative 2016-04-26 PRELIMINARY Harold R. Cutler, P.E. Consulting Fire Protection Engineer 165 Landham Road Sudbury, MA 01776 -3156 Voice & fax 978-443-7088 Email hcutlercfpe@verizon.net April 22,2016 P/N 2526 Northampton Building Department Puchalski Municipal Building 212 Main St. Northampton, MA 01060 Attention: Louis Hasbrouck Building Commissioner Dear Mr. Habrouck: Subject: Request for Acceptance of Compliance Alternatives Two Means of Egress Conditions and Exit Enclosure Requriements Dawes House at Smith College 8 Bedford Terrace, Northampton, MA This letter is submitted on behalf of the Facilities Management Office of Smith College and Morgan Studio, the architect for the proposed renovation project at Dawes House, 8 Bedford Terrace. It is submitted to request your department’s consideration and acceptance of three compliance alternatives in accordance with Section 101.5.0 of the Existing Building Code of Massachusetts (EBCM) with respect to the following conditions in the building: 1. The single means of egress from the Second and Third Floors. 2. The lack of an enclosure of the means of egress stair from the Second and Third Floors. 3. The lack of a complying occupancy separation between the First Floor spaces of Use Group A-2 from the Use Group B spaces of the Second and Third Floors. In addition to references to the EBCM, this letter will also refer to the requirements of the Eighth Edition of the Massachusetts State Building Code (MSBC8) for new construction. Existing Conditions Key characteristics of the existing building for purposes of this discussion may be summarized as follows: Louis Hasbrouck, NBD Page 2 April 22, 2016 PRELIMINARY 1. Construction type is Type VB based on the building’s wood frame construction. 2. The building’s story height is three stories and basement. 3. The building area is approximately 3,720 sf based on the footprint of the building. 4. The aggregate area of all stories is 11,830 sf. 5. The primary existing occupancy classification is Use Group B (Business) for the gluten free dining facility with kitchen on the First Floor. 6. In addition, the existing Second and Third Floors are presently classified in Use Group R-2 but are vacant. 7. An automatic system-connected smoke detection system is provided in the common rooms and corridors of all three levels that will activate horn-strobe alarm notification devices throughout the building. 8. Automatic sprinkler protection is provided throughout the building. 9. Means of egress from the First Floor is provided by two doors to the exterior from the dining facility and one door to the exterior from the entry lobby serving the upper floors. 10. Means of egress from the Second and Third Floors is based on exit access corridors and aisles leading to one unenclosed exit stair. Proposed Renovations and Expansion The proposed project will include renovations within the existing First Floor gluten free dining facility to expand the dining area and create a new kitchenette and new toilet facilities. As a result of the increased occupant load, the dining facility will undergo a change in occupancy from Use Group B to Use Group A-2. The proposed renovations and alterations on the First Floor are documented on the Phase III project plans. At this time, the extent of renovations and alterations including upgrading of utilities (electrical, plumbing, communications) on the Second and Third Floors are undefined and not planned for immediate implementation. Ultimately, those spaces will be used for “swing space” for college departments during renovations in other campus buildings. We believe several of these existing and new characteristics and features of the building may be recognized as compliance alternatives to strict compliance with respect to the three issues identified above. Those separate issues are discussed below. 1. Compliance Alternative for Number of Upper Story Means of Egress The existing means of egress stair from the Third to Second to First Floors that is to remain terminates at the First Floor entry lobby at which level occupants leave that lobby to the new porch on the front and side of the building. An existing second stair from the Second to First Floors of very poor quality and requires discharge through the entry lobby is to be demolished. There are no exterior stairs or fire escapes serving the upper stories. Louis Hasbrouck, NBD Page 3 April 22, 2016 PRELIMINARY EBCM Section 705.3.1 concerning means of egress in a building undergoing Level 2 alterations permits a single means of egress from certain buildings in accordance with the following exception: 2. Group B, F-2, and S-2 occupancies not more than two stories in height that are not greater than 3,500 square feet per floor (326 m2 ), when the exit access travel distance does not exceed 75 feet (22 860 mm). The minimum fire-resistance rating of the exit enclosure and of the opening protection shall be 1 hour. The Dawes House conditions do not satisfy these restrictions because (1) the building has three stories that would have a single means of egress, (4) the existing access travel distance including travel over the unenclosed stairs to the First Floor door to the exterior would be 122 ft and (3) the existing stair is unenclosed. MSBC8 Section 1021.2 and Table 1021.2 have similar restrictions for single exit stories of buildings in new construction but specify and occupant load limit of 29 persons for a single exit second story. The characteristics and features of Dawes House that we believe compensate for the lack of a second means of egress from the Second Floor include the following: 1. The complete automatic sprinkler protection of the building that is not a condition of EBCM Section 705.3.1 or MSBC8 Table 1021.2 and provides a high level of life safety for building occupants who are not intimately involved in an ignition event. 2. The installation of a smoke detection system in the common areas of all three stories would not be required under the code provisions for new construction for this building that is not of a residential occupancy. 3. The low calculated total occupant load of the Second and Third Floors of 45 persons. 4. The modest travel distance of 122 feet from the most remote point on the Third Floor to the front door to the exterior. 5. The isolation of the exit access stair and exit discharge lobby from the remainder of the First Floor spaces. The actual common path of travel distance (Item 4) may be compared to the Code’s allowance for a maximum common path of travel distance of 100 feet within a sprinklered, single means of egress space of Use Group B occupancy. The exit access travel distances of Item 4 may also be compared to the Code’s allowance of 250 feet of exist access travel distance in Table 1016.1. Louis Hasbrouck, NBD Page 4 April 22, 2016 PRELIMINARY 2. Compliance Alternative for Lack of Stair Enclosure The same factors as discussed above compensate for the lack of enclosure of the three story means of egress stair of the building. An exit stair enclosure is intended to protect occupants when evacuating a building from fire conditions in spaces adjacent to the means of egress path. In a sprinklered building of Use Group B occupancy, common path of travel distances of up to 100 feet are permitted that are not required to be protected from adjacent spaces. That distance is compared to the 122 feet of common path of travel that will exist from the most remote point on the Third Floor of Dawes House. It is proposed to provide a continuous and complete (but unrated) separation of the First Floor dining facility and kitchens from the First Floor entry lobby and conference room. That barrier will be made up of a combination of existing and new partitions. That barrier will prevent or delay the impact of a fire problem in the dining or kitchen areas on the exit access path to the front door. Approved Compliance Alternatives EBCM Section 101.5.0 (MA amendment) references examples of compliance alternatives found at the frequently-asked-questions (FAQ) link on the Board of Building Regulations and Standards web site. Two of those compliance alternatives address the conditions resulting that are the subjects of requested Compliance Alternatives 1 and 2. The presence of the non-required common area smoke detection system will compensate for the extra travel distance required for egress from the Third Floor with its single means of egress and the lack of exit stair enclosure by providing an early warning that permits early evacuation of the apartment. Such conditions are addressed in Section 2.3 of the FAQ discussion of enclosures of exits that states the following: 2.3 Enclosure of exitways: 2.3.1 General Compliance alternatives: 1. Improve enclosure of exitway. 2. Add a partial fire suppression system. 3. Add a detection system The travel distance issue in this case is the length of the single, unenclosed vertical exit access path from the Third Floor offices to the First Floor entry lobby door to the exterior. A second suggested compliance alternative with respect to travel distance, in FAQ Section 2.2, states the following: 2.2 Travel Distance: 2.2.1 General Compliance Alternatives: 1. Add detection system. Louis Hasbrouck, NBD Page 5 April 22, 2016 PRELIMINARY 2. Add a partial fire suppression system. 3. Add smoke doors. 4. Increase fireresistance rating of corridor walls and doors Occupancy Separation A consequence of the change of occupancy to Use Group A-2 on the First Floor is a requirement from EBCM Section 912.5.1 that the building shall comply with the height and area limitations of the MSBC8 for new construction. If the building were arranged as separated mixed Use Groups A-2 and B and the Use Group A-2 space were limited to the First and Second Floors, the height limitation would be satisfied in accordance with MSBC8 Section 508.4.3. That requirement would be satisfied if there were a one-hour rated occupancy separation between the A-2 and B spaces. It is proposed to consider the occupancy separation to be the combination of (1) the walls separating the First Floor assembly and kitchen spaces from the entry lobby, conference room and unisex toilet and (2) the Second Floor assembly above the Use Group A-2 spaces. Such use of existing wood lath and plaster wall and ceiling assemblies is explicitly permitted by the exception in EBCM Section 912.5.3 that state: Exception: Where the fire barriers are required to have a 1-hour fire-resistance rating, existing wood lath and plaster in good condition or existing 1/2-inch-thick (12.7 mm) gypsum wallboard shall be permitted. We request acceptance of a compliance alternative to allow the combination of existing and new wall and floor-ceiling assemblies to be considered a comparable occupancy separation. The conditions and characteristics of the building that are the basis for that request include the following: 1. The Use Group A-2 occupancy will be limited to the First Floor. 2. The installation of a smoke detection system in the common areas of all three stories would not be required under the code provisions for new construction for this building that is not of a residential occupancy. 3. The new walls on the First Floor will be constructed to have a one-hour fire rating. 4. The existing walls are acceptable for occupancy separation purposes in accordance with EBCM Section 912.5.3. 5. The existing deck of the Second Floor floor-ceiling assembly will provide a smoke barrier with some inherent fire resistance between the First and Second Floor above the Use Group A-2 space. The locations of the partitions and floor/ceiling assemblies described above are indicated on the attached “Dawes House Occupancy Separation.pdf. Louis Hasbrouck, NBD Page 6 April 22, 2016 PRELIMINARY Approved Compliance Alternatives EBCM Section 101.5.0 (MA amendment) references examples of compliance alternatives found at the frequently-asked-questions (FAQ) link on the Board of Building Regulations and Standards web site. One of those compliance alternatives addresses the condition that is the subject of requested Compliance Alternative 3. That compliance alternative suggests the following with respect to building assemblies required to be fire rated: 3.1 Fire separations and partitions; 3.1.1 General compliance alternatives: 1. Improve fire separation. 2. Add a fire suppression system. 3. Add a detection system. In the case of Dawes House, the smoke detection system is a non-required system that will alert building occupants long before the lack of a complete fire rating of the occupancy separation becomes a factor in the safety of building occupants. Conclusions On the basis of the above analysis of the hazards and protection characteristics of Dawes House, we request your acceptance of the above listed features and characteristics as compliance alternatives to the code requirements related to the indicated means of egress requirements and occupancy separation requirements of the code for existing or new construction. Thank you for your cooperation. Very truly yours Harold R. Cutler cc: Elizabeth Morgan, MS