Dewey Hse Comp Alt 052112
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
May 21, 2012
P/N 2135
Office of the Building Commissioner
Puchalski Municipal Building
Northampton, MA 01060
Attention: Louis Hasbrouck
Building Commissioner
Dear Mr. Hasbrouck:
Subject: Request for Acceptance of a Compliance Alternative
Means of Egress Stair Enclosure
Dewey House, Smith College
This letter is submitted on behalf of Smith College, the owner of Dewey House on the
Smith College Campus and Kraus-Fitch Architects, the architect for the current
renovation project at the building. It is submitted to request your department’s
consideration and acceptance of a compliance alternative in accordance with Section
101.5.0 of the Existing Building Code of Massachusetts (EBCM) with respect to an exit
stair enclosure and continuity requirements.
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:
1. The existing construction type is Type VB based on combustible exterior and
interior structural elements and floor and roof assemblies.
2. The building has three stories and a basement.
3. The building’s dimensional height is approximately 24’ above average grade
measured from average grade to the average height of the existing peaked roof.
Louis Hasbrouck, NHBD Page 2 May 21, 2012
4. The building area is approximately 3,500 sf based on the footprint of the building
inside the exterior walls.
5. The aggregate area of the above grade stories is 8,289 sf.
6. The basement (strictly mechanical and storage) has an area of 3,275 sf.
7. The primary existing occupancy classification is Use Group B (offices).
8. One conference room and one seminar room that are less than 750 sf in area are
also classified as Use Group B occupancy based on MSBC8 Section 303.1,
Exception 3.
9. The building is fully sprinklered.
10. The building will be provided with a new fire detection and alarm system that will
be activated by the sprinkler system waterflow detector and by manual pull
stations at the entrances to exits on all four building levels.
11. The fire alarm system includes a connection to the Smith College Campus Police
Dispatch Office at Mt. Holyoke College. That office is manned 24/7 and calls in
the alarm notification to the Northampton Fire Department and Campus Police
Officers stationed at the Smith College Police Office.
12. The means of egress is based on exit access corridors and aisles leading to one
enclosed exit stair (Stair 3) and a combination of two unenclosed stairs (Stair 2
and Stair 1) serving the Second and Third Floors.
13. The first floor is served by doors to the exterior at grade at two locations.
Proposed Renovations
The building is undergoing general renovations and alterations primarily for the purpose
of improving life safety, energy performance, accessibility, and other envelope and
structural improvements (roof framing, roofing, siding, etc.) There are very few
programmatic changes being made at this time.
In addition, it is proposed to remove an existing partition at the Second Floor that is
used to separate the existing historic Stair 1 between the First and Second Floors from
the Second Floor corridor system. Stair 1 is a continuation of the means of egress path
from the Third Floor that involves travel down Stair 2 from the Third to Second Floors,
across a portion of the Second Floor to Stair 1, down Stair 1, across a portion of the
First Floor and to a door to the exterior from the First Floor.
The means of egress path of concern is illustrated on the attached Plan A0.1.
Strict compliance with the EBCM provisions for existing buildings and MSBC8
provisions for new construction would require that Stair 1 and Stair 2 be enclosed and
that they would provide a continuous path from the Third Floor to the exterior at the First
Floor.
Compliance Alternative Request
Your acceptance of a compliance alternative to the exit stair enclosure and continuity
requirements for Stairs 1 and 2 is requested.
Louis Hasbrouck, NHBD Page 3 May 21, 2012
One provision of the Eighth Edition of the Massachusetts State Building Code (MSBC8)
that allows an unenclosed stair to serve as a means of egress stair is in Exception 4 of
Section 1016.1. That exception states:
4. In other than occupancy Groups H and I, exit access
travel distance is permitted to be measured from the
most remote point within a building to an exit using
unenclosed exit access stairways or ramps in the first
and second stories above grade plane in buildings
equipped throughout with an automatic sprinkler system
in accordance with Section 903.3.1.1. The first
and second stories above grade plane shall be provided
with at least two means of egress. Such interconnected
stories shall not be open to other stories.
When a stair is unenclosed in accordance with either of these exceptions, travel over
the stair is considered to be exit access that is subject to the exit access travel distance
limits of Table 1016.1. For the Use Group B occupancy of this sprinklered building, that
limit is 300 feet.
Exception 4 provides a basis for acceptance of the proposed compliance alternative as
a one-story extension of its unenclosed stair allowance. The conditions imposed by
Exception 4 except the story height limitation are satisfied by conditions in Dewey
House. First, the maximum travel distance from the most remote location on the Third
Floor to an exit to the exterior on the First Floor is approximately 152 feet using Stairs 1
and 2. That distance is well under the maximum allowable exit access travel distance of
300 feet permitted for the Use Group B occupancies in a sprinklered building. Second,
the building is fully sprinklered. Third, the interconnected First and Second Floors are
not connected to the Third Floor due to the separation between Hall C200C2 and
Corridor 200C1.
Our request for acceptance of this compliance alternative is based on multiple features
and characteristics of the building including the following:
1. The calculated occupant loads of the Second and Third Floors served by the
unenclosed stair are 11 and 21 persons respectively based on the individual
areas of those floors of 2,034 sf and 1,073 sf respectively and an occupant load
factor of 100 sf.
2. The actual occupant load of the Second and Third Floors served by the
unenclosed stair will likely be slightly under this as there are only 6 small offices
on the third floor and 11 small and 4 large offices on the second floor. All of
these offices are private, single occupancy for professors, where occasional
meetings with one or two students occur.
3. The building is provided with an automatic sprinkler system that provides a high
probability of life safety for all building occupants except those intimately involved
Louis Hasbrouck, NHBD Page 4 May 21, 2012
in an ignition event.
4. The building is provided with a fire detection and alarm system that will be
activated by manual pull stations and sprinkler system waterflow detectors.
5. The remote locations of the primary exits from each floor will allow building
occupants at most locations to move away from a perceived threat.
6. The horizontal subdivision of the First and Second Floors at the midpoints of
those floors by a smoke resistant partition provided with doors on magnetic hold-
open devices that will serve as barrier to smoke spread between the separate
halves of the building.
7. The maximum travel distance on the Third Floor to the enclosed Stair 3 or the top
of Stair 2 is 51 feet.
8. The maximum travel distance on the Second Floor to the enclosed Stair 3 or the
top of Stair 1 is 58 feet.
9. The maximum travel distance on the First Floor to a door to the exterior is not
more than 56 feet.
10. The maximum travel distance from the most remote point on the Third Floor
down Stair 2, across the Second Floor to the unenclosed Stair 1, down Stair 1
and across the First Floor to a door to the exterior is not more than approximately
152 feet.
11. The exit access travel distances listed in Items 7, 8, 9 and 10 are compared to a
maximum allowable exit access travel distance of 300 feet permitted for the Use
Group B occupancies in a sprinklered building.
12. The upper levels of the building are within reach of fire department ground
ladders and aerial ladders.
13. The existing glass enclosure at the top of the Stair 1 juts out into the corridor and
impinges the means of egress from approximately 3’-8” to approximately 3’-0”.
This situation cannot be improved upon without the removal of the enclosure in
question.
14. An existing enclosure at the Third Floor at the top of Stair 2 will be retained and
will provide isolation of the Third Floor from the Second Floor.
15. A magnetic hold open will be added under this project at the third floor at the top
of Stair 2. This is an enclosure door that has repeatedly been found to be
propped open, defeating the purpose of the enclosure. This addition will be an
improvement to the life safety.
If Dewey House were limited to two stories in height, the historic Stair 1 would be
permitted to remain unenclosed in accordance with MSBC8 Section 1016.1, Exception
4, and to serve as a required means of egress stair. An allowance to have the
unenclosed means of egress stairs extend to the Third Floor only adds 11 persons to
the occupant load served by that means of egress. Those persons have a second exit
stair available to them directly from the Third Floor.
Conclusions
The proposed removal of the Second Floor enclosure of means of egress Stair 1
extends the allowance of MSBC8 Section 1016.1, Exception 4, for an unenclosed stair
Louis Hasbrouck, NHBD Page 5 May 21, 2012
to serve as a means of egress stair by one extra story. However, that change has little
impact on the conditions in the building affecting the safety of building occupants
including the fire detection and alarm system that will provide an early warning of a fire
condition and the short travel distances to interior and exterior exits. The overall small
size of the building will facilitate fire department operations inside and outside the
building.
Our Request
On the basis of the above analysis of the hazards and protection characteristics of
Dewey House, we request your acceptance of the above listed features and
characteristics as a compliance alternative to the code requirements related to the
enclosure and continuity of one of the two means of egress from the building.
Thank you for your cooperation.
Very truly yours
Harold R. Cutler
cc: Laura Fitch, KFA
From:Louis Hasbrouck
To:"Laura Fitch"
Subject:RE: Dewey House - compliance alternative
Date:Thursday, May 31, 2012 11:21:00 AM
Laura,
I will accept the compliance alternative that you’ve presented regarding the historic
stairway in Dewey House, 4 Neilson Drive in Northampton, with the condition that the guard rail
at the top of the stairway be raised to 42”. The guard rail must match the existing handrail in
keeping with the historical elements of the stairway.
Louis Hasbrouck
Building Commissioner
City of Northampton
Town of Williamsburg
212 Main Street
Northampton, MA 01060
(413) 587-1240
From: Laura Fitch [mailto:lfitch@krausfitch.com] Sent: Monday, May 21, 2012 7:30 PMTo: Louis HasbrouckCc: Charlie ConantSubject: Dewey House - compliance alternative
Dear Louis,
Attached please find a request for acceptance of a compliance alternative for the second floor
enclosure of the historic curved stair at Dewey House. I’ve also attached the Egress plans that are
part of the permit set you have already received.
We would like to remove the glass enclosure at the top of the stair, and Hal Cutler has reviewed
the situation and concurs that there are sufficient reasons to consider this.
Thank you for your consideration. Please let me know if you have any questions.
Laura Fitch, AIA, LEED BD+C
Kraus-Fitch Architects, Inc.
110 Pulpit Hill Rd.
Amherst, MA 01002
413-549-5799
lfitch@krausfitch.com
www.krausfitch.com
Board Member US Green Building Council, Western Mass. Chapter
http://www.usgbcma.org
Board Member of the Cohousing Association of the US
www.cohousing.org