CITY OF CHICAGO REVISES LIGHT AND VENTILATION ORDINANCE

Mayor's initiative will help promote construction activity in city
by Gregg Garmisa, Vice President, WMA Consulting Engineers, Ltd.

If you want to know what national architects and urban planners think of Mayor Daley, go directly to the source. Alice Sinkevitch, the executive director of the American Institute of Architects' Chicago chapter, recently summarized her organization's feelings about our mayor following a speech he gave to the national group: "There wasn't anyone in that room who wouldn't have been willing to take him home and make him mayor of the city where they lived."

What's true nationally is largely true within the local design and real estate development community. The difference is, we get to see the small strokes, the nitty-gritty details worked on by the Mayor and his administration, as well as the end results.

A case in point: In mid-1997, Mayor Daley, Buildings Commissioner Cherryl Thomas, and Director of Code Review Harold Olin convened a technical task force to review and recommend changes to the city's code provisions covering natural light and ventilation standards. The work product of this Task Force was recently submitted by the Mayor to the City Council as a proposed ordinance. It passed on April 29 and took effect May 20, 1998.

It may not be the stuff of which dreams are made, but the city's vintage light and ventilation standards threatened to cut off significant high-rise, loft conversion and residential activity. Hence, the city-sanctioned task force and new ordinance, which are the first steps in a process which will later include modifications to the entire Mechanical Code.

For the Light and Ventilation Task Force, WMA's President, Gabe Reisner, P.E. and this attorney were asked to join a select group of engineers, developers, architects, and contractors to work with city officials and draft language which forms the backbone of the new standards. The guiding principles of the Task Force, prior law, resulting problems under the old standards, and central features of the revised provisions are summarized below.

THE GUIDING PRINCIPLES      (Top)

As enunciated by the Mayor's initiative for this task force and the subsequent Building Code overhaul, the public policy goals include the following:

  • First and foremost, the revisions have to be consistent with the Building Code's primary emphasis on securing public safety, health and welfare.
  • The new code should be innovative and serve as a model, reflective of existing model codes, such as BOCA, but also cognizant of unique conditions important to the City of Chicago.
  • The revised code should increase predictability and consistency for users, thereby minimizing the prospects of inconsistent interpretations and case-by-case analysis.
  • The amended ordinance should endeavor to promote economic development and adaptive re-use of buildings by lessening impediments posed by unnecessarily restrictive and out-dated provisions.

PRIOR LIGHT AND VENTILATION STANDARDS      (Top)

Guided by the foregoing parameters, the Task Force convened. The first step consisted of a review of the existing requirements for natural light and ventilation in Chicago. Briefly summarized, in residential and related settings, the Chicago Code historically required both natural light and ventilation. More specifically, the city required: 1) such structures to provide natural light, with a minimum glazed area of at least 10% of the floor area of the room, and no less than 10 sq. ft.; and 2) such structures to provide natural ventilation through means of openings to the outside air having an aggregate clear area of not less than 5% of the floor area of the room.

CENTRAL PROBLEMS WITH OLD LAW     (Top)

The Task Force unanimously agreed that these so-called "10-5" standards for residential settings were steeped in turn-of-the-century notions of healthy living conditions and/or disease transmission methods which have lost much of their credibility over the passing decades. Modern research shows that mechanical ventilation can promote the public welfare as well as natural ventilation, and sometimes can even exceed the perceived benefits of window openings.

Equally significant, the 10-5 requirements were considered overly restrictive. Two examples confronted by Chicago developers prove that point:

  1. There is an abundance of unused older commercial space in the general downtown area that is ripe for loft conversion, but the 10-5 standards make such adaptive reuse prohibitively costly in many circumstances. To be more precise, Chicago is in the midst of an unprecedented building boom, but recent vacancy rates for reusable commercial space in and around the loop remain high (20% of older space in the CBD; 30% in the South Loop; and 25% in the East Loop). Revising the light and ventilation standards would promote adaptive reuse without compromising the public welfare.

  2. Existing office buildings, which are not required to have natural ventilation, could not be converted to residential, hotel or related use without the replacement of existing windows and the likely loss of large areas of interior spaces under the 10-5 rules. That is precisely the dilemma faced by a hotel developer which proposed conversion of a new, prime ---but largely vacant--- office property into a luxury hotel. The ambitious project could not be accommodated under the old code, leaving the unfortunate, and entirely unnecessary, prospect of a fully developed, but grossly underutilized, 20 story high-rise.

NEW LIGHT AND VENTILATION STANDARDS     (Top)

To address these problems, the Task Force looked for guidance, in part, from a model code promulgated by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE). Under ASHRAE, natural light and ventilation rates of 8% and 4%, respectively, are considered modern and appropriate standards. Equally significant, ASHRAE explicitly condones the substitution of mechanical ventilation for natural ventilation under certain circumstances.

The Task Force unanimously recommended the adoption of the 8% and 4% requirements for natural light and ventilation. Yet, these changes, while significant, would not solve the problems confronting loft-conversion projects, which typically have large floor plates, and resulting deep, interior rooms, which had to be ventilated and provided with natural light. Similarly, the modifications would not address the cost-prohibitive issues involved in the adaptive reuse of other, mechanically ventilated buildings for future residential and related purposes.

The Task Force, therefore, suggested two other significant amendments to the Code. The first, and most important, addition was the recommendation that so-called "multi-purpose rooms" in family dwellings should be exempted from the 8% and 4% requirements for natural light and ventilation. Under the new Code, a multi-purpose room is defined as "a room within a family dwelling unit which may be used as a study, office, multimedia room, or other function normally associated with family dwelling occupancy, and which room is in excess of the essential family needs for living, dining and sleeping."

Such a multi-purpose room is exempted from the general requirements if, but only if, certain enumerated criteria are met. First, such rooms are explicitly prohibited from being used as sleeping rooms. Second, mechanical ventilation and artificial light provided to these spaces must meet code requirements. Third, a multi-purpose room or rooms cannot exceed 15% of the total floor area of the dwelling unit. Fourth, the dwelling unit must have a minimum of one bedroom if the unit has a floor area of 1,300 sq.ft. or less, and two bedrooms if the floor area exceeds 1,300 sq.ft. And, finally, the exemption only applies to existing buildings constructed pursuant to a permit issued prior to April 1, 1998.

In a related provision, the Task Force recommended that the City should retain, but modify, requirements applicable to interior rooms or spaces that borrow natural light or ventilation. The net effect of this change will ease the standards applied to borrowed light or ventilation in remote rooms.

The second change allows mechanical ventilation in hotel and hospital patient rooms in lieu of natural ventilation. Under the previous code provisions, mechanical ventilation would only be allowed in those settings if the building had an atrium and the rooms subject to the exception faced that atrium. The new provision is more reflective of today's recognition that air conditioned accommodations are as desirable, and sometimes more desirable, than natural ventilation.

Following the Administration's review, Mayor Daley submitted these recommendations to the City Council on April 1, 1998. Alderman Stone's Buildings Committee endorsed the package on April 24 and the full City Council ratified the ordinance on April 29. The new light and ventilation standards took effect May 20, 1998.

CONCLUSION     (Top)

Mayor Daley has embarked on an ambitious course to modernize Chicago's Buildings Department. Perhaps the most important and fundamental step in that process is to revise the laws which govern real estate development activity in the city. The recent passage of the new light and ventilation standards is a clear indication that Chicago means business. If that experience is any indication of the improvements intended for the broader Mechanical Code, it bodes well for residents of Chicago and the construction industry generally.

ABOUT THE AUTHOR     (Top)

Gregg Garmisa, an attorney, is Vice President of WMA Consulting Engineers, Ltd. Mr. Garmisa serves as a member of the Task Force on Light and Ventilation, and the Task Force on the Mechanical Code. For additional information about the new light and ventilation standards, please contact Mr. Garmisa at (312) 786-4310 or GGarmisa@wmace.com.