New York City is set to initiate a major code change that will affect the design and installation of certain types of exterior wall assemblies. The language is specific to combustible exterior wall coverings, which include exterior insulation and finish system. The result of this change will make EIFS more complex and therefore more expensive in its installation on projects within the city. This is an example of a local municipality adopting a model code such as the International Building Code and locally makes it more stringent through amendment.
On June 14, 2017, Grenfell Tower, a residential high-rise located in Kensington, West London in the United Kingdom, caught fire. The entire tower soon became engulfed in flames. The BBC reported 72 deaths, and the fire was determined to have started in a kitchen on a lower floor. Fire then breached a window and ignited the exterior cladding. This conflagration spread both vertically and laterally around the building. The cladding on the tower was not EIFS; it was an aluminum composite panel in combination with combustible insulation.
Once the cause of a catastrophic event is determined, building code language is typically reviewed and modified to minimize the probability that it could happen again. The first reaction to the Grenfell Tower fire was for the New York City Department of Buildings to express its inclination to ban the use of exposed foam plastic on exterior walls. The department’s intentions were later altered to the final code language, which accepted EIFS but required fire blocking.
The United States has fire test protocols that are specific to the spread of fire both laterally and vertically on the outside of a building. NFPA 285, Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Wall Assemblies Containing Combustible Components, is an established test that must be successfully undertaken to assure code acceptance for EIFS. It is referenced in the IBC along with exceptions for fire blocking when the proposed assembly has been tested according to NFPA 285. There are many triggers written into the code mandating the use of this test.
The New York Building Code now reads as follows: “EIFS installations containing foam plastic insulation shall be fireblocked in accordance with Section 7184.108.40.206.”
Reviewing 7220.127.116.11.1, Locations, the requirement states that noncombustible fireblocking is necessary to control the spread of fire through concealed spaces. It is to be installed “around wall openings; in alignment with the slab edge, for a height of not less than 8 inches and at maximum intervals of 20 feet vertically; and between different occupancy groups, horizontally or vertically, as applicable.”
Further, NYC Buildings Bulletin 2022-013 dated Sept. 6, 2022, lists the applicable code sections and describes the requirements for fire blocking of combustible exterior wall assemblies. In general, as noted above and with minor exceptions, fireblocking is required around wall openings, slab edges and between different occupancy groups.
Fireblocking material is defined in Section 718.2.1, and for EIFS applications it will presumably result in the inclusion of non-combustible insulation. Mineral wool is recognized as non-combustible and could be used at locations where fireblocking is required or used as an acceptable replacement for the foam plastic insulation that would have then covered the entire wall. Either solution affects the level of complexity and cost to the standard EIFS installation. Alterations in the typical sequencing of an EIFS installation will have to be considered to accommodate the installation of the fireblocking.
After Nov. 7, 2022, when the new requirements go into effect, contractors who work in New York City will be challenged to be code compliant and cost efficient while maintaining tight construction schedules. This change has been in the making for several years, so when it is implemented and enforced, local contractors ostensibly have had time to research viable solutions.
Ironically, these tighter requirements on EIFS come at a time when the city is also embarking on a strategy to reduce building emissions primarily through the reduction of energy consumption. Local Law 97 now requires that any building over 25,000 square feet must have its total emissions reduced by 40% by 2030 and 80% by 2050. This is an aggressive endeavor, and one where reducing operational energy will focus on the efficiency of the exterior envelope. The EIFS Industry Members Association has been leading industry efforts and as a result there should be an ameliorating evolution to this code requirement. However, there is a concern that this language may migrate to other municipalities. Contractors should be up-to-date regarding New York City code language and stay current on EIFS requirements.
Robert Grupe is AWCI’s director of technical services. Send your questions to email@example.com, or call him at (703) 538.1611.
Want more articles like this? Subscribe to AWCI's Construction Dimensions for free now.