This is a follow-up to my April 2, 2018 blog post on column misalignment in E. Sibley Hall, Cornell University. As a result of that blog post (contained in an email to relevant parties), a new study was commissioned. One year later, the report was submitted to Cornell, but I was not permitted to see it. Finally, after meetings and email communication, the Dean of the College of Architecture, Art, and Planning agreed to make the report accessible to me, and I read it today in the Dean’s Office. Following is an edited version of my email response to that report, sent to all relevant parties.
I have reviewed the “Global Stability Study: Sibley Hall, Cornell University” prepared by Ryan Biggs Clark Davis Engineering & Surveying (dated April 23, 2019) and, in particular, the portion of the report that deals with column misalignment in E. Sibley Hall. In general terms, the report supports my observations from April 2, 2018, but there are several problems with the report that need to be addressed. In particular, their structural analysis appears to assume rigid joints between wooden roof elements rather than pinned joints, and ignores the role played by the steel girder supporting the attic joists.
The report has two key findings:
The report notes that “tie rods (installed in 2015) provide tension resistance at the skylight openings but do not provide resistance in compression. Under additional load, due to snow or other loading, additional inward deflection of the columns is likely.” [Executive Summary, p. iii]
The report notes that “at the third floor, many of the interior columns are not plumb. … In general, the tops of the columns lean toward the center of the building.” [p. 12]
However, the structural model shown in their Appendix C, in particular drawing SK-4, does not accurately represent the 3-dimensional nature of the actual structure. Specifically, joints between wooden elements are assumed to be rigidly connected, rather than pinned, and there is no mention of the steel girder holding up the attic joists. As I stated in my April 2, 2018 email, “the inward bowing of the steel girders over the misaligned columns on the third floor of E. Sibley … indicates that these girders—designed to transfer the gravity loads of the roof structure to the columns—are now also acting as parabolic tension chains, resisting the further inward movement of the columns and attic joists. Clearly, these girders were not intended to act in this manner, and there has been no mention, in either the Assessment report or in Silman’s structural drawings, of this potentially dangerous condition.”
In other words, the latest structural analysis in the April 2019 report continues to misunderstand the structural behavior of the E. Sibley roof, and has modeled the structure in a way (i.e., with rigid joints for wood elements) that underestimates the danger inherent in the structure, while completely missing the role played by the steel girder in holding this unintended “mechanism” together. The report also notes that the new tension cables are slack and notes that they don’t provide “resistance in compression,” but somehow does not draw any conclusions about the fact that the engineering assumptions that led to the specification of these cables—made by Silman Associates—were flawed.
Rigid connections are extremely difficult to achieve in wooden construction, especially where there are no steel gusset plates or other types of bolted or riveted connecting devices. It seems unreasonable (and unsafe) to make such assumptions for the ordinary wooden roof structure in E. Sibley Hall. Furthermore, the assumption of rigid joints is not even explicitly stated in the report; only the curvature (caused by internal bending) in the wooden roof elements modeled in Figure 4 gives us any clue as to the underlying assumptions used.
One further comment on the cracks noticed in E. Sibley Hall (especially in Room 144 ES). The report describes “cosmetic cracks noted in East Sibley and the diagonal crack in Room 144 of East Sibley” and suggests that they “may be associated to minor movements or vibrations associated with the construction of Milstein…” [p. 19]. The report fails to note the underpinning of the Sibley foundations during the construction of Milstein Hall which effectively “lifted” the masonry structure on top of an unstable new foundation wall (unstable since it had not yet been backfilled or tied back). This condition undoubtedly contributed to the problem of wall movement. Here’s what I wrote in my Milstein Critique in 2013: “While no officially-sanctioned study of the causes of these masonry cracks has been made public, one plausible explanation is that inadequately-braced foundations, together with excessive vibrations from caisson drilling, contributed to the cracking (Figures 5 and 6). The century-old foundations of East Sibley Hall were underpinned by creating a new reinforced concrete foundation wall under the existing shallow foundation. However, no tiebacks were used to prevent lateral movement of this new wall, which runs in an east-west direction. Some combination of lateral thrust originating in the brick arches cut into the perpendicular (north-south) walls and from the mansard roof above, along with vibrations from the drilling of caissons immediately adjacent to this new wall, may have triggered these substantial cracks in the perpendicular masonry walls of E. Sibley Hall. That is, the entire north wall of Sibley Hall appears to have moved laterally towards the excavated Milstein Hall construction site, because (1) the arches in Sibley Hall already provided a discontinuity—a line of weakness—in the perpendicular bracing walls; (2) a horizontal force (thrust) was already present in those walls due to the action of the arches themselves as well as the geometry of the Mansard roof above; (3) the vibration of the masonry structure by caisson drilling facilitated the cracking of relatively weak brick mortar joints; and (4) the laterally-unbraced underpinned foundation wall was able to rotate on its footing since no horizontal tie-backs were provided.”
I believe that Ryan-Biggs misunderstood the problems with the E. Sibley structure in their earlier “Building Envelope and Structural Conditions Assessment” from 2009, and that their current report is still inadequate. It would have been useful, in any case, to have provided them with my own analysis.
Today, I filed a formal complaint with the New York State Division of Building Standards and Codes concerning fire- and life-safety violations in the Mui Ho Fine Arts Library in Rand Hall at Cornell University. This complaint contains essentially the same material that I submitted to the City of Ithaca on April 1, 2019, but in addition contains, as an appendix, the City of Ithaca’s response, along with my commentary on their response.
Links to all my writings about the Mui Ho Fine Arts Library in Rand Hall at Cornell University can be found here.
Figure 1. Cornell Chronicle parody headline created by J. Ochshorn
After I noticed column misalignment, slack tension cables, unintended girder curvature, and sloping attic joists in the newly-renovated Frances Shloss Studios on the third floor of East Sibley Hall, I requested information from Cornell about its structural design and, on March 21, 2018, was provided with a structural conditions assessment that had been prepared by Ryan-Biggs Associates in 2009, as well as four pages of structural plans prepared by Robert Silman Associates in March 2015.
On April 2, 2018, based on my examination of these documents, I sent a detailed, though speculative, critique of the structural design to various interested parties, including the director of facilities for Cornell, the director of facilities for the College, and the Director of Code Enforcement for the City of Ithaca. My critique suggested that the consulting engineer’s structural analysis was flawed, not only misrepresenting the behavior of the existing structure but detailing new structural elements that might well have triggered or worsened structural misalignments in the nineteenth-century building. The next day, Ithaca’s Director of Code Enforcement sent me the following note: “Thank you very much for copying me on your email, as of yesterday I am following up on it. Based on your excellent detailed analysis and photos documenting the conditions, I share your concern.”
Cornell—rather than heeding my advice to engage the services of an independent consulting engineer who was not involved in producing the Assessment report or the structural drawings for the E. Sibley renovation—hired Ryan-Biggs Associates to assess the conditions in East Sibley Hall, the same firm that did the initial conditions assessment in 2009. It took over a year for this process to come to a conclusion and, having finally received the report from Ryan-Biggs, Cornell is now refusing to release it. I received the following explanation from the College’s facility director on May 3, 2019: “Hi Jonathan, The report was paid for and is the property of Facilities & Campus Services. It isn’t a public document that I can share. However, I can share that the final results showed that the East Sibley structure is sound and there is no need for additional reinforcement at this time.”
Hence, the Cornell Chronicle parody headline above (Figure 1). I have not been told what top-secret or otherwise sensitive information is in the report that precludes its release. The original structural engineer for the third-floor renovation, Robert Silman—who died in 2018—is a well-respected Cornell alumnus who, as explained here, was influential in directing some of architect Edgar Tafel’s estate to Cornell as a gift. Is there something in the Ryan-Biggs report that might implicate Silman’s firm in a negative or embarrassing way? Is the condition of East Sibley Hall “sound” because of their structural design, or in spite of their structural design? How did the latest Ryan-Biggs report model current structural conditions (i.e., as conventional roof rafters creating an outward thrust or as a collection of unstable mechanisms tending to rotate inward)? Was a dynamic analysis used to assess the response of this highly unusual structure to wind and earthquake forces? How were nineteenth-century clamps—intended to connect girders to the columns for gravity loads only—assessed in terms of their capacity to resist dynamic tension forces induced by winter blizzards or seismic events (Figure 2)? Were members of Cornell’s facilities staff embarrassed by their role as facilitators of this flawed design project? Or did the report conclude that all structural design assumptions for the third-floor renovation were valid, that the supervision and execution of the project was properly done, and that, therefore, all of my concerns were unfounded? None of these questions can be answered unless Cornell releases the report. The City of Ithaca Building Division should require Cornell to submit the report as evidence that the structural renovation meets standards outlined in the New York State Building Code (thereby making the report public), but the Building Department has shown little interest in holding Cornell accountable when it comes to Code compliance.
Finally, the misalignment of the third-floor East Sibley columns—whether caused by or just exacerbated by the Shloss Studio renovations; and whether presenting an imminent threat to safety or not—should be corrected.
Figure 2. The left image shows column misalignment on the third floor of East Sibley Hall, with tension cables effectively pulling the columns further out of vertical alignment; the right image shows a nineteenth-century clamp connecting girders to columns, a fastener never intended to resist tension forces induced by the columns pushing laterally on the girders (photos by J. Ochshorn, May 4, 2019)
On a related note, Cornell’s College of Architecture, Art, and Planning (AAP) has also refused to include news about my Title-19 code complaint—which outlines numerous life- and fire-safety violations in the Rand Hall Mui Ho Fine Arts Library—in its “News & Events” postings, or any of its other social media venues. Demonstrating contempt for academic freedom by engaging in egregious “viewpoint discrimination,” Cornell AAP has chosen to censor my critique of life- and fire-safety violations, not because it isn’t newsworthy or of interest to its target audience, but because Cornell administrators oppose its point of view and, apparently, fear an open and vigorous debate about these important issues.
I submitted a formal code complaint today about the Mui Ho Fine Arts Library in Rand Hall at Cornell University. As far as I can tell, the project—under construction and expected to open before the Fall 2019 semester begins—has at least nine substantial fire safety and life safety violations, all explained in my complaint document:
Violation #1: Unenclosed egress stair in the atrium.
Violation #2: Inadequate number of plumbing fixtures in the roof-top bathrooms.
Violation #3: Fifth floor incorrectly labeled as mezzanine within the atrium.
Violation #4: Lack of 1-hour horizontal assembly between the atrium and roof-top spaces.
Violation #5: Smoke control system does not protect building occupants.
Violation #6: Elevator too small for an ambulance stretcher.
Violation #7: Allowable story height exceeded for library occupancy without Type I construction.
Violation #8: Allowable floor area is exceeded at the second story.
Violation #9: Vertical openings in bookstack floors.
This schematic section through Rand Hall (Figure 8 in my formal code complaint; drawn by J. Ochshorn) illustrates just one of the nine code violations I have identified: a smoke control system that does not “provide a tenable environment for the evacuation or relocation of occupants” as the New York State Building Code requires.
All of my writings about the Rand Hall library project are linked from this website.
[Updated below: Feb. 27, 2019] I have just received written confirmation from a Senior Staff Architect at the International Code Council (ICC) that the unenclosed stairs in Cornell’s Fine Arts Library atrium are noncompliant with the International Building Code (IBC), and that the roof-top gallery above the atrium is also noncompliant as designed. The 2015 New York State Building Code is derived from the IBC and contains the same Code language cited in the Code opinion by ICC. Of course, this Code opinion has no legal force, but it does indicate that the fire safety problems I have identified are real and need to be addressed. Here is the written opinion in full:
Date: Thursday, February 14, 2019 at 11:17 AM Re: 2015 IBC Sections 404.6, 1005.3.1, 1017.3.1, 1019, 1023.1, 1023.2,
Question 1: Can the path of egress travel to an exit pass through more than one adjacent story in an atrium?
Answer 1: There is nothing saying someone could not follow the stairway in the atrium as a path of egress travel for as many stories as they wanted. However, if the stairway in the atrium is a considered a required exit access stairway, the egress path for the required means of egress (i.e. number of exits off of a floor) can only go down one story till occupants could choose to move to the required exits (1006.3.1, 1017.3.1, 1019). If the stairway in the atrium is considered a required exit stairway, while Section 1023.2 Exception 2 does allow for the atrium to meet the construction requirements for the exit stairway, the atrium must meet all the remaining provisions for an exit stairway in Section 1023, including termination at the exterior, not be used for any other purpose other than exit (e.g. no uses on the ground floor of the atrium) and no paths that go through the atrium to get to the 2nd exit.
Question 2: Can an unenclosed interior exit stairway, as permitted in Section 1023.2 Exception 2, terminate in the middle of an atrium floor that is above the level of exit discharge.
Answer 2: No. Exit stairways must discharge directly to the exterior (1023.1) and cannot stop at an upper floor. There are the options for the stairway to discharge through a lobby or vestibule (1028), however, this lobby cannot be within the stairway/atrium enclosure and it cannot be at other than the level of exit discharge.
Question 3: Does an occupied roof (Group A-2 assembly) above an atrium need to be separated from the atrium with a 1-hour horizontal assembly?
Answer 3: Yes, an atrium must be separated from occupied spaces. While a roof is not a story, it is an occupied space, so it must be separated from the atrium where the floor of the occupied roof is over the atrium. Where an occupied roof floor is around the atrium, a separation would not be required.
Code opinions issued by ICC staff are based on ICC-published codes and do not include local, state or federal codes, policies or amendments. This opinion is based on the information which you have provided. We have made no independent effort to verify the accuracy of this information nor have we conducted a review beyond the scope of your question. This opinion does not imply approval of an equivalency, specific product, specific design, or specific installation and cannot be published in any form implying such approval by the International Code Council. As this opinion is only advisory, the final decision is the responsibility of the designated authority charged with the administration and enforcement of this code.
I hope that this answers your question in full. Please feel free to contact me again if you have any additional questions on this issue.
Kimberly Paarlberg, RA
International Code Council
Codes and Standards, Senior Staff Architect
5332 Woodfield Drive, Carmel, IN
888-422-7233, Ext. 4306
[February 27, 2019 update: I just received a code interpretation from the New York State Division of Building Standards and Codes that agrees in full with the ICC answers shown above (“We reached the same conclusions as did the ICC representative, Kimberly Paarlberg”). I have forwarded their response to the City of Ithaca Director of Code Enforcement and other parties involved in this fiasco. Depending on how they react, I may well need to file a formal complaint.]
Links to all my writings on the Fine Arts Library at Cornell can be found here.
I’ve invited Christine Sheppard, Ph.D. to give a talk at Cornell on Friday, Nov. 2, 2018 at 4:45 pm in 101 West Sibley Hall on the subject of bird-friendly design. The talk is open to the public and free. Continuing education credit (one LU/HSW credit) is available for architects and LEED APs or Green Associates.
Rand Hall at Cornell University (photo and PhotoShopped window and bird by Jonathan Ochshorn, Oct. 2018)
Date, time, and place: Friday, November 2, 2018, 4:45 pm in 101 West Sibley Hall, Cornell University
Abstract: Birds are potent cultural symbols. They play fundamental roles in ecosystems and habitat regeneration and are important natural controls for insects. Hundreds of millions are killed yearly by colliding with glass in the US alone. Birds cannot see glass, striking it as they fly towards reflections of clouds, sky and vegetation or as they approach real habitat seen through glass. Birds collide with glass on structures of every size, from shacks to skyscrapers, in urban, suburban and rural area. Advances in technology are increasing use of glass curtain walls and other large glass features, increasing the rate of mortality.
Until recently, this problem has been almost unrecognized as an issue of sustainability. However, the Green Building Council has responded by adding a Pilot Credit, Reducing Bird Mortality, to the LEED rating system. Toronto, San Francisco, Oakland and the state of Minnesota now mandate bird-friendly construction in some cases and more legislation and voluntary guidelines are pending. Moving into the future it will be increasingly necessary to design structures with impact on birds in mind.
This class explains how to recognize hazards to birds in the built environment. Case studies and a slide show illustrate many currently available strategies for reducing bird mortality and how bird-friendly design can add value to strategies often deployed to control heat and light or promote security. We review use of the LEED credit and important features of legislation. Techniques now in use for evaluating the relative threat level to birds of different materials are described, along with typical results.
Continuing education credits: Available for registered architects/engineers as well as LEED APs and Green Associates.
Short bio: Christine Sheppard earned her B.A. and Ph.D. in Ecology and Evolutionary Biology at Cornell University. Working with Dr. Tom Cade, who used captive breeding to restore the Peregrine Falcon to the eastern US, developed her interest in captive propagation as a tool to save endangered species. This led her to the Wildlife Conservation Society’s Bronx Zoo, where she started as curatorial intern, in 1978, and ended as Curator and Chair of the Ornithology Department. Zoos deal not only with issues of their buildings causing mortality of wild birds. Glass exhibit walls, windows and handrails bring bird collision problems inside and curators have a vested interest in finding ways to make glass safe for birds. Interest in the issue led to Dr. Sheppard to join the board of the Bird-safe Glass Foundation as science advisor, in 2007; she became President in 2017. She is also conducting basic research into quantifying the effectiveness of different materials and patterns in preventing bird collisions. In 2009, she moved to the American Bird Conservancy as Collisions Program Director. She authored both editions of ABC’s publication, Bird-friendly Building Design. She has also created AIA/LEED continuing education classes on Bird-friendly Design. She helped create San Francisco’s Standards for Bird-safe Buildings and has subsequently been involved in creating code and legislation in many different jurisdictions. She led the team that developed USGBC LEED Pilot Credit 55: Reducing Bird Mortality. She was named an Engineering News-Record Top 25 Newsmaker for 2014 because of her work on glass testing and has worked with most major glass manufacturers on design and evaluation of bird-friendly materials.
[Updated Oct. 8, 2018 and Oct. 15, 2018]: [October 8, 2018 update: I just made a video based on the blog post below. Also, I’ve removed two of the six mezzanine “issues” I had initially written about: first, the 200-foot limit for exit access travel within the atrium doesn’t prevent a different path of exit access travel from being compliant, since only one of the two egress paths (the shortest) defines the exit access travel distance; second, while I still think that the area of the so-called mezzanine at the roof level is greater than half of the area of the atrium below, it’s too hard for me to definitively measure such floor area to be absolutely sure. There is the additional issue that the open-air roof gallery is not exactly “sprinklered,” so it’s unclear if it’s area should be 1/3 or 1/2 of the room it is in. In any case, there are still four problems with the roof-top mezzanine assumption being argued by Cornell and the City of Ithaca, any one of which would render the Rand Hall Fine Arts Library scheme noncompliant. These four remaining problems are explained below, and in the video.]
I received an email yesterday from the Director of Code Enforcement for the City of Ithaca Building Division claiming that Cornell’s proposal for a fifth-floor roof gallery—above the Fine Arts Library now being constructed in Rand Hall—was actually a mezzanine within the atrium below. This is important since a 5-story building would be absolutely noncompliant, whereas a 4-story building (with mezzanine)—while still egregious—is supported by numerous Code variances that Cornell has obtained over the years. The Building Division Director wrote: “The roof top gallery must meet the code requirements for a mezzanine otherwise the building is non-compliant. I have discussed this issue with the design team several times and have been assured that it will be sized so that it does meet the code requirements for a mezzanine. The sizing of the roof top area must include the permanently enclosed space at that level and all the open area that can be occupied. I do not believe that the code requires the mezzanine to be open to the atrium because the mezzanine has two exits.”
He then quoted a portion of the 2015 NYS Building Code (based on the 2015 International Building Code, or IBC) which seems to support his argument: “Exception 2. A mezzanine having two or more exits or access to exits is not required to be open to the room in which the mezzanine is located.”
In response, I replied as follows (where all references to the Code can be found here):
You have quoted only part of the mezzanine requirements, which state that a mezzanine need not be open to the room in which the mezzanine is located if it meets certain criteria (having at least 2 exits). However, there are six other criteria for qualifying as a mezzanine that the roof gallery does not meet. If even one of the following six criteria is not met, then the building, as designed, is noncompliant.
1. The definition of a mezzanine in Chapter 2 of the 2015 IBC states that a mezzanine is “an intermediate level or levels between the floor and ceiling of any story and in accordance with Section 505.” Clearly, the open roof gallery is not between a floor and a ceiling of any space, since there is no ceiling above it. Therefore, it is not a mezzanine.
2. The definition of an atrium in Chapter 2 of the 2015 IBC states that an atrium must be “closed at the top.” Therefore, it is impossible to include an open-air roof gallery as part of an atrium, since the atrium, in that case, would not be “closed at the top.”
3. Section 505 states that a mezzanine must be “in” the room for which it is so designated, not “on top of” the room, as is the case with the roof gallery. Specifically, Section 505.2.1 states: “The aggregate area of a mezzanine or mezzanines within a room shall be not greater than one-third [can be increased to one-half with sprinklers] of the floor area of that room or space in which they are located.” [emphasis added]. This section twice reiterates that the mezzanine must be “within” or “in” the room or space. This is not just a figure of speech, but is deliberate and important. Mezzanines are allowed to have certain fire safety benefits, unlike ordinary stories, precisely because they are “in” another room, where occupants of the mezzanine are more aware of any fires that may originate in that room, since the mezzanine has what used to be called a “common atmosphere” with the room in which it is located. Being “in” the room is therefore integral to the very essence of a mezzanine, whether or not the “opening” between the mezzanine and the room it is in has been closed off per the exception; the advantages of being “in” the room still apply. It is improper to ignore that part of the definition, and just look at the requirements for maximum area. If one used only the logic of maximum area, then any space, say a third-floor office, could be considered a mezzanine of a larger second-floor space that happened to be below it, even if there were no logical connections between the two spaces, but only a vertical adjacency.
4. It is also problematic to even consider that an atrium can have a mezzanine within it, since atriums are just “openings connecting two or more stories … which are closed at the top and not defined as a mall. Stories, as used in this definition, do not include balconies within assembly groups or mezzanines that comply with Section 505.” What this definition refers to when it states that mezzanines do not count as stories is not a mezzanine within the atrium (which would make no sense), but rather a mezzanine adjacent to the atrium, i.e., within a story surrounding the atrium opening. Only a conventional room or space can have a mezzanine. An atrium is not a conventional room or space, but rather is defined as an “opening” adjacent to such rooms or spaces. Once “mezzanine” floor area is inserted into an atrium, that floor area is, by definition, no longer an opening between stories, and so cannot be part of the atrium. Rather, it would be part of the adjacent stories that surround the atrium.
[Oct. 8, 2018 update] Issues #5 and #6 are no longer applicable, for the reasons explained in the update note at the top of the blog post. 5. Even if the roof gallery were considered as a mezzanine within the atrium, it still would be noncompliant, since Section 404.9.3 of the 2015 IBC limits the “portion of the total permitted exit access travel distance that occurs within the atrium” to no more than 200 feet. If the gallery is considered as a mezzanine within the atrium, then the exit access travel distance within the atrium, measured from the most remote point of the roof gallery, and following the atrium exit access stair “B” all the way down to the 2nd-floor exit, would be far greater than the 200-foot limit for exit access travel distance “that occurs within the atrium.”
6. The total area of the enclosed and open occupied spaces at the roof level (what is being called a mezzanine) is approximately 2,275 square feet; whereas the floor area of the atrium (measured at the 2nd floor) is approximately 4,335 square feet. Therefore, the so-called mezzanine exceeds the allowable area, based on the atrium floor area.
You correctly state that the building is noncompliant if the roof-top gallery, including all enclosed and occupied open spaces on the roof, does not qualify as a mezzanine. I think it is clear that—for the 6 reasons given above—the roof-top occupied spaces cannot be considered as a mezzanine. Therefore, the building is noncompliant.
Please reconsider your preliminary Code interpretation and let Cornell and their architects know that their notion of a roof-top mezzanine cannot be logically sustained.
[October 19, 2018 update]
On October 4, 2018, I asked the Director of Facilities for Cornell’s College of Architecture, Art, and Planning (copied to many other relevant parties, including the Director of Code Enforcement for the City of Ithaca Building Division, Mike Niechwiadowicz) to “confirm whether the entire roof structure of Rand Hall—including all columns that support the roof, and all beams that brace those columns, and all floor decks that brace the beams that brace the columns—has a 1-hour fire rating? This is important since an atrium, per 2015 IBC Section 404.6, needs to be separated from all adjacent spaces by a 1-hour horizontal assembly and/or fire barrier; as you know, there is an occupied space above the atrium’s roof that would need to be separated from the atrium by 1-hour fire-rated construction.”
On October 15, 2018, I got the following reply: “All the supporting elements, columns, braces, and floors, have a one hour rating. There was a variance granted by the state to not fireproof the horizontal roof steel. In regards to the roof, Per Tim D. from GHD, it is outside of the building and not a space within the building and therefore does not need a one hour separation. Also, the penthouse is a mezzanine to the atrium below and therefore does not need to be separated.”
On October 16, 2018, I responded as follows: “Thanks for the detailed answers. The occupied space above the atrium remains extremely problematic. Cornell’s 2016 Code variance was granted on the basis of an atrium roof with no occupied spaces above it, and so the variance cannot be applied to the current scheme. Section 404.6 of the 2015 Building Code specifically requires that ‘atrium spaces shall be separated from adjacent spaces by a 1-hour fire barrier … or a horizontal assembly…’ The occupied roof-top gallery is clearly an ‘adjacent space’ and so must be separated from the atrium with a 1-hour horizontal assembly. Cornell is claiming—improperly—that the roof-top occupancy is actually a mezzanine within the atrium below; this is a transparent attempt to get around the prohibition of a fifth story and the prohibition of an occupied space above a non-fire-rated atrium roof (horizontal assembly). But what Cornell is calling a mezzanine violates both the definition of mezzanine and the definition of atrium in Chapter 2 of the Code, not to mention the requirement that a mezzanine be ‘within’ a space or room [see detailed explanation below]. And as Mike has written to me previously, if the roof-top gallery space is not a mezzanine—which it clearly isn’t— the whole scheme is noncompliant.
“Please ask the design team to reconsider their plans for a fifth-floor above the atrium. It is likely that a formal complaint will be filed with the City of Ithaca and, if necessary, with the New York State Division of Code Enforcement and Administration if construction goes forward as currently planned—unless you can explain to me why none of the four reasons I have listed below applies to the current proposal. Please respond to my specific questions about the mezzanine designation, i.e., why you believe that every one of the four reasons I have cited below is incorrect. I’ll email again in a couple of weeks before initiating the complaint process, hoping that common sense will prevail during that time period.”
Then, on October 19, 2018, I wrote a follow-up email to the the Facilities Director (and other relevant parties): “I just re-read your email dated Oct. 15, 2018, and now am totally confused about Cornell’s intentions with respect to the roof gallery. Mike Niechwiadowicz wrote that the building permit for the Ho Fine Arts Library was granted on the basis of the roof gallery being treated as a mezzanine within the atrium. Your quote from Tim D. from GHD, on the other hand, implies that the roof gallery is not only not a mezzanine, but is not even a relevant consideration, being ‘outside’ of the building. Let me quote from Mike’s email to me, dated Oct. 4, 2018: ‘The roof top gallery must meet the code requirements for a mezzanine otherwise the building is non-compliant. I have discussed this issue with the design team several times and have been assured that it will be sized so that it does meet the code requirements for a mezzanine. The sizing of the roof top area must include the permanently enclosed space at that level and all the open area that can be occupied.’ [emphasis added]
“So please clarify how the roof gallery is being considered from a fire safety (Building Code) standpoint. On the one hand, if it is being considered as a mezzanine, then my comments in the prior email stand. On the other hand, if it is being simply ignored, please consider the following explanation as to why that latter standpoint is equally flawed.
“You wrote: ‘In regards to the roof, Per Tim D. from GHD, it is outside of the building and not a space within the building and therefore does not need a one hour separation.’ There are two claims here, amounting to the same thing: (1) The roof gallery is outside the building; and (2) the roof gallery is not a space within the building. From these two claims, the conclusion is drawn that the atrium does not need to be separated from the occupied roof gallery by a 1-hour fire-rated horizontal assembly.
“But the Code, and common sense, do not support this conclusion. First, from the Code: Section 404.6 states that ‘Atrium spaces shall be separated from adjacent spaces by a 1-hour fire barrier… or a horizontal assembly…’ Any adjacent (occupied) space—not only an adjacent ‘story’—needs to be separated from the atrium. But is the roof gallery part of the building? The 2015 Building Code specifically identifies ‘occupied roofs'” as being part of the building since, per Section 1006.3, ‘The means of egress system serving any story or occupied roof shall be provided with the number of exits or access to exits based on the aggregate occupant load served in accordance with this section’; and the means of egress is defined as ‘a continuous and unobstructed path of vertical and horizontal egress travel from any occupied portion of a building or structure to a public way…’ Since means of egress systems are, by definition, in buildings; and since occupied roofs must have means of egress, it follows that occupied roofs are part of buildings. One could put this in the form of a logical syllogism:
Major premise: Means of egress systems are in buildings (Definition, Chapter 2).
Minor premise: Occupied roofs must have means of egress (Section 1006.3)
Conclusion: Occupied roofs are part of buildings.
“From all this, it follows that the occupied roof gallery is not only a space adjacent to the atrium (which is really the only relevant criterion), but is also part of the building, contrary to the unsupported assertion made by Cornell’s Code consultant. The requirement in Section 404.6 is for separation of the atrium from ‘adjacent spaces,’ not only from adjacent stories. And an occupied roof is both a ‘space’ and a space that is part of the building.
“Second, based on common sense: Hundreds of assembly occupants may gather on the roof gallery above the atrium and their safety is threatened by placing them above an atrium without any fire-rated separation. This is what the 2015 ‘Code Commentary’ says about the need for fire-rated enclosure: ‘One of the basic premises of atrium requirements is that an engineered smoke control system combined with an automatic fire sprinkler system that is properly supervised provide an adequate alternative to the fire-resistance rating of a shaft enclosure. It is also recognized that some form of boundary is required to assist the smoke control system in containing smoke to just the atrium area. The basic requirement, therefore, is that the atrium space be separated from adjacent areas by fire barriers and horizontal assemblies having a fire-resistive rating of at least 1 hour.’ [emphasis added] The current scheme not only violates this basic requirement for separation, but also violates the explicit logic of a smoke control system (i.e., ‘in containing smoke to just the atrium area’) by venting atrium smoke—not harmlessly into the outside air—but rather right at the roof level, immediately adjacent to the occupied roof gallery itself! I’ve noted previously that the exit access stairway will also serve as a smoke vent system when its door is opened, thereby making egress from the roof gallery even more precarious. If your intention was to design a building that puts occupants at maximum risk, you have succeeded admirably.
“Mike Niechwiadowicz has written explicitly that ‘the roof top gallery must meet the code requirements for a mezzanine otherwise the building is non-compliant.’ Since the roof gallery is not a mezzanine, the building is non-compliant. All other Code interpretations seeking to justify this dangerous proposal are equally flawed.
“I’m still eager to hear back from you before I initiate a formal complaint.”
Without the Code variances that have been granted, Cornell’s Rand Hall Fine Arts Library, as a Type V-B building with A-3 occupancy, would be limited to two stories; as it is, the current proposal (including the anticipated roof-top pavilions) is for a five-story building. The proposal, without the variances, would also greatly exceed the allowable per-floor area permitted by the Code, owing to its attachment, without any fire wall separation, to Milstein and Sibley Halls.
Not only does the current proposal exceed the height limits granted by prior variances, but the variances themselves do not even appear to apply to the current proposal at all, since the prior variances were for a 3- or 4-story library, not a 5-story library. This is a classic bait-and-switch move, entirely unjustified by any fire science rationale.
I have already written extensively about the flawed logic underlying these Code variances and also underlying the Fine Arts Library proposals themselves, so I won’t repeat those arguments.
What I will comment upon are the new (for me) Code analysis drawings supplied by the architects that are now available in the Architecture, Art, and Planning Dean’s Office, based upon which a building permit was granted.
There are at least five serious Code violations that I have noticed in these new drawings:
1. The art gallery will become a fifth story as soon as even temporary pavilions are constructed. As such, these pavilions would not be permitted under the Code, even given the already egregious assumptions made about Code compliance for the proposed 4-story building. Because these pavilions are not shown in the drawings, any such construction will require a new building permit, even if the pavilions are only temporary. The pavilions will not be compliant if the Code is followed, since an A-3 assembly space (art gallery with pavilions) is not permitted above the third floor of a sprinklered Type II-B building, and certainly not on the fifth floor.
2. The entire egress strategy for the building, based on having unenclosed interior exit stairs in the atrium, is flawed, to the extent that it is based on 2015 IBC Section 1023.2, exception 2. This section allows interior exit stairways to forgo construction of otherwise required fire-barrier enclosures if they are within an atrium enclosed per 2015 IBC Section 404.6.
However, 2015 IBC Section 404.6 requires the atrium to be separated from adjacent spaces (not only adjacent “stories” but any adjacent “spaces”) by a 1-hour horizontal assembly (and/or fire barrier). There is an occupied space above the atrium (the roof-top art gallery) and yet a 1-hour fire-rated horizontal assembly is not provided that would separate the atrium from the art gallery above. In fact, there are even roof hatches designed to pop open in the event of fire, between the art gallery and the atrium, a strategy which completely violates both the spirit and letter of this Code requirement. Since the requirements of Section 404.6 are not met, having unenclosed interior exit stairways in the atrium is not permitted (and, of course, the atrium itself is noncompliant).
3. Along those lines, the architect’s Code drawings incorrectly state that the second-floor slab provides a non-required 1-hour horizontal fire barrier as per variance 2015-0432. First, there is no such thing as a horizontal fire barrier (it would be called a horizontal assembly). Second, this 1-hour fire rating is not discretionary, but is absolutely required, in order to separate the first floor occupancy from the atrium above. It does not provide “extra” fire safety beyond Code requirements, as is implied.
4. The atrium is improperly labeled; it is drawn as if it consisted of the entire space within the exterior walls of Rand Hall, above the first floor and excluding the “bump” on the southern side. In fact, the atrium consists only of an “opening connecting two or more stories” and not the stories themselves. Therefore, all the stack floor areas are not part of the atrium itself, but are simply stories, adjacent to the atrium, for which atrium smoke calculations must be made. This means that the justification for the roof-top mezzanine is flawed, since it is based on a calculation that its area is no greater than 1/2 the area of the “atrium” it is in. But the mezzanine as drawn is not “in” the atrium; only the stair to the mezzanine is conceivably in the atrium, while the rest of the mezzanine is directly over the stack floors and the mechanical room serving Milstein Hall. It therefore does not qualify as a mezzanine, but would be considered a fifth story.
5. Glazed openings in Stairway A appear to be too close to glazed openings in the southern wall of Rand Hall (unless this glass has a sufficient fire-rating, which is not indicated in the drawings I have examined). Per 2015 IBC Section 1023.7: “Where nonrated walls or unprotected openings enclose the exterior of the stairway or ramps and the walls or openings are exposed by other parts of the building at an angle of less than 180 degrees, the building exterior walls within 10 feet horizontally of a nonrated wall or unprotected opening shall have a fire-resistive rating of not less than 1 hour. Openings within such exterior walls shall be protected by opening protectives having a fire protection rating of not less than 3/4 hour. This construction shall extend vertically from the ground to a point 10 feet above the topmost landing of the stairway or ramp, or to the roof line, whichever is lower.”
[Update Aug 26, 2018: Correction made to the statement in the second paragraph contending that prior Code variances were for a 3-story building. In fact, Cornell’s third, 2016, variance was for a 4-story building, although its logic was entirely flawed. Since the current proposal, purported to be for a 4-story building, is actually for a 5-story building, the argument I am making—that prior variances do not apply to the current proposal—still stands.]
[Update: Oct. 23, 2018] Latest image showing highly-reflective glass—just installed for the Fine Arts Library project in Rand Hall at Cornell University—inviting bird collisions:
Photo by Jonathan Ochshorn, October 23, 2018
According to the Rand Hall Fine Arts Library’s June 18 to June 29, 2018 construction activity highlights and project update: “A full mock up window has been installed on the northern facade. It can be viewed from the sidewalk on University Avenue.”
Rand Hall’s highly reflective trial window appears as an opening to sky and trees, inviting bird collisions.
Based on the trial window, shown in the image above, it seems likely that these highly-reflective windows will be problematic for birds: the windows appear (to the birds) as openings to trees and sky, thereby inviting collisions. There are better bird-safe glazing techniques that are widely known, for example using patterns on the glass that mimic the multi-pane steel-framed “factory” windows that were recently removed. For more information, see the American Bird Conservancy website.
[Update: July 9, 2018] Here’s another image of the same highly-reflective window.
Another image of Rand Hall’s highly-reflective glazing.
[Updated Oct. 16, 2018: The image below shows how it looked on Oct. 8, 2018, with a few more windows installed.]
View on Oct. 8, 2018 (photo by Jonathan Ochshorn)
Additional writings and blog posts on the Rand Hall Fine Arts Library project are linked here.
I just read an article in the May 2018 ASHRAE JOURNAL about Discover Elementary School in Arlington, Va. designed by VMDO Architects; it is currently the largest zero energy elementary school built in the US. It’s interesting to compare its size, cost, and “sustainable” qualities with Cornell’s LEED gold-certified Milstein Hall, the architecture building designed by OMA and Rem Koolhaas. Both are two-story academic buildings.
Size (sq. ft.)
Cost ($ millions)
OFF-SITE Energy USED
So, in a nutshell, Milstein Hall is half the size, twice the cost,* and barely meets minimum ASHRAE energy standards,** while the Arlington school actually returns energy to the grid.
Aerial views of the Discovery Elementary School in Arlington, VA (top) and Milstein Hall at Cornell University (bottom)
*To be clear, the Arlington school is half the cost and twice the size; in other words, its cost per square foot is approximately 25% that of Milstein Hall.
**Cornell’s stated goal (see my video) since 2008 is for new buildings “to use 30% less energy than current energy standards and strive towards 50% less energy.” Milstein Hall’s energy model projects a whopping 2% energy reduction compared to this minimum standard.