Fall 2023, Vision Issue 16: Mechanical Considerations for Partial Renovation Projects

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Mechanical Considerations for Partial Renovation Projects Generally speaking, renovation projects can fall into one of two categories: partial renovation or total building overhaul. Typically, a partial renovation or addition is the more challenging of those project types and requires substantial multi-trade coordination. Just some of the challenges that are faced during a renovation are explained in this article. Structural Implications 1. Importance of Surveying Existing Conditions During design, engineers make a strong effort to survey existing beam heights and depths, as well as the location of existing penetrations, to ensure there is space for the new design. If field measurements are inaccurate, it can lead to more challenges in construction. In order to avoid that scenario, as design engineers, we conduct multiple field surveys to detail these constraints and compare them with the existing drawings to confirm potential routing, in areas where the ceiling is not accessible. 2. The Use of Existing Beam Penetrations and Risers Reusing existing penetrations and chases minimizes both the cost and coordination needed for the project, provided the new and existing systems are similarly sized. A downside of reuse, however, is that it locks the engineer into designing around field conditions that cannot not always be confirmed until demolition. 3. Additional Supports for New, Heavier Equipment The addition of heavy equipment such as air handling units, chillers, and cooling towers could necessitate supplemental supports. The structural

implications of system updates add cost and complexity to a project. As such, it is important that potential equipment locations are coordinated with the structural engineer as soon as possible in design.

Image 1: Existing Beam Penetration

Space Limitations 1. Limits on MER Space Energy recovery wheels might need to be added to meet current code requirements. This increases the overall unit size and footprint of the mechanical space required which might pose a challenge to new programming intents. 2. Low Floor-to-Floor Height and More Economical System Types If an existing building was constructed without HVAC, the floor-to-floor height could pose a challenge when fitting ductwork to meet modern ventilation and air conditioning requirements. Often, this situation prompts the design of a system with local heating and cooling (fan coil units, chilled beams, VRF) and a dedicated outdoor air system (DOAS), minimizing the ductwork size. Connecting to Existing Systems 1. Existing Versus As-Builts It is common for existing buildings to have undergone multiple renovations, some of which might not be documented. If possible, it is important to request As-Built drawings. Although existing ALL TEXT ©2023 KOHLER RONAN, LLC

design drawings are helpful, As-Builts will show the engineer how a design may have been altered in the field during construction. When such documentation is not provided, more field surveys will be conducted. 2. Testing and Air Balancing Oftentimes, there is intent to reuse existing equipment in a renovation. The full feasibility of that intent is not known until a pre-construction air/ water balancing report is done. Then, the engineer can determine if additional capacity needs to be added to serve the proposed new programming. 3. New Programming Versus Existing Systems The proposed architectural design might not allow the use of existing conditions due to ceiling height limitations or wall relocations. If existing piping or ductwork is located below the new ceiling height, it is critical to communicate with the architect and establish a minimum height for service runs. Additionally, if programming calls for a new room which encroaches on an existing shaft, the engineer will either have to relocate the existing systems or coordinate another solution. “Mechanical Considerations…” continued on page 2

IN THIS ISSUE Mechanical Considerations for Partial Renovation Projects


Lithium-ion Batteries and the Implications for Fire Protection


Did You Know?


Project Highlight


SUPPLEMENT Getting Up-to-Speed on Connecticut Plumbing Codes

“Mechanical Considerations…” continued from page 1

4. Useful Life Issues Existing piping or ductwork that is in poor condition will have to be replaced. These systems or elements could be past their useful life due to decay over time, the presence of asbestos insulation, or even improper installation. The need for updating and/or replacing piping and ductwork leads to more demolition of the existing system as well as changes to tie-in points. Anticipation of Adjustments During Construction 1. Impact of Field Conditions on the Construction Administration Process Unforeseen issues may arise throughout the construction administration phase of renovation projects. These issues include inaccuracies in existing design drawings, existing system scope, or undocumented structures that was not previously captured. When such issues arise, the design team is presented with Requests for Information (RFIs), which call for coordination between the design engineer, architect,

and the contractor in order to find a solution to these unforeseen challenges. Sometimes, RFIs result in meetings where we consider potential options, based on the design and relevant existing conditions. The aim is to make adjustments without adding cost to the project. Other times, it might be necessary to weigh options requiring slight design modifications, such as moving a new ductwork tap further upstream of an existing main to achieve the desired airflow. 2. Phasing and Coordination with the Owner When looking at existing systems, it’s important for an engineer to consider how a project might be phased. The owner must be alerted to inevitable downtime which will affect the building’s operations and occupants. For example, if it were discovered that there were no isolation valves on the existing chilled water piping lines, this would mean that there would be no way to temporarily disconnect the chilled

water running through the entire building from the chilled water piping project’s scope. In order to renovate this area, then, the chilled water throughout the building would need to be drained down completely, leaving many classrooms and office spaces (out of the project’s scope) without cooling until the system was back online. As is hopefully clear following the discussion above, partial renovation projects require a thorough consideration of the facility’s mechanical systems. There are structural implications and space limitations, as well as a host of challenges stemming from the need or desire to reuse and/or connect to existing systems. Field surveys are of critical importance; this cannot be overstated. A final piece of advice prior to engaging in renovation projects is to anticipate adjustments to systems designs during the construction phase. It is not uncommon that unforeseen issues arise, and it is best to be prepared for that eventuality.

Lithium-ion Batteries and the Implications for Fire Protection Lithium-ion Batteries Pose Serious Fire Protection Challenges Any great technological advancement will have some risks; this is no different with the development of the lithium-ion battery. The benefits of this technology include a higher energy density, faster charging, and longer life than traditional lead-acid batteries. To date, these batteries can be found in cellphones, tablets, electric vehicles (EVs), laptops, e-bikes, hoverboards, wheelchairs, scooters, tools, and solar-power, backup storage equipment. Despite their increasing use, they are still not without concerns. The most recent concern with lithium-ion batteries occurs when the batteries (which are made up of numerous cells) fail or break down as a result of the following: • Overcharging • Severe Temperatures (either hot or cold) • Physical Damage • Manufacturer Defect • Exposure to Moisture

Any of the above issues can cause “thermal run-away” when the batteries break down, creating large amounts of heat and toxic gases (CO, CO2, and Hydrogen). These

gases can in turn propagate quickly and violently to the next battery. “Lithium-ion Batteries…” continued on page 3

MEP 2040 Challenge Kohler Ronan is pleased to join a growing number of MEP/FP industry leaders in accepting the MEP 2040 Challenge posed by the Carbon Leadership Forum (CLF). As signatories, we are committed to “advocate for and achieve” net-zero operational and embodied carbon by 2030 and 2040 respectively, across all our projects.

Approved Technical Consultant in NY & CT – Incentive and Rebate Assistance Kohler Ronan is an approved Technical Consultant providing valuable assistance to clients interested in accessing incentives in both New York and Connecticut. In New York, we are approved under NYSERDA’s Commercial New Construction Program and also serve as an Independent FlexTech Consultant. As part of the Energize Connecticut initiative, Kohler Ronan is approved for projects within Eversource and United Illuminating territory. Under each of these programs, our professionals provide technical support in the form of energy modeling and controls commissioning to assess and identify appropriate energy efficiency opportunities for new construction and substantial renovation projects. For details, please email Madhav Munshi at mmunshi@kohlerronan.com.


“Lithium-ion Batteries…” continued from page 2

Recommendations for Containing and Preventing Lithium-ion Battery Fires Firefighting foam is not recommended for lithium-ion battery fires, and gaseous extinguishing systems are not effective in “open” areas. Meanwhile, specialized dry powder (cell block containment system for lithium-ion batteries) is designed for the total immersion of smaller devices and is not appropriate for EV fires. Because these batteries are encased for the purpose of keeping out water, water itself does not always work effectively to stop the thermal run-away nor propagation. Further, the extreme temperatures at which these batteries burn mean that larger water flow rates, measured in gallons per minute or GPM, are required to extinguish them. As a result of the numerous fire incidents involving lithium-ion devices and the clear challenges in fighting them, recommendations have been developed to address the handling and use of these batteries. Changes in the relevant building and/or fire code are also being implemented to improve safety. Currently, the National Fire Protection Association (NFPA), the International Code Council (ICC), and FM Global have proposed recommendations: NFPA 13, 2022 (referenced by the 2024 model codes) Increase the fire sprinkler design density in parking garages from Ordinary Hazard Group 1 (OH1), 0.15 gpm/sf to Ordinary Hazard Group 2 (OH2), 0.20 gpm/sf over the most remote 1,950 square feet (for dry sprinkler systems) + 250 gpm hose stream allowance. FM Global (for FM Global insured properties) While Data Sheet 7-15 Garages does not explicitly list electric vehicles, it does include an increase in design density to an FM Global Hazard Class 3 (HC-3), due to the increased combustible load from electric vehicles (plastics, batteries, etc.). Hazard Class 3 requires: 0.30 gpm/sf over the most remote 3,500 square feet (for dry sprinkler systems) + 500 gpm hose stream allowance. This would also require sprinkler heads with a “K” factor orifice size of 11.2.

Building Code The 2021 International Building Code requires the presence of sprinkler systems in open parking garages when the fire area exceeds 48,000 square feet or 55 feet in height. The 2024 editions of NFPA 101 and NFPA 5000, both of which reference NFPA 88A, “Standard for Parking Structures,” will require sprinklers at even lower thresholds. The 2023 edition of NFPA 88A removed all exceptions to open parking sprinklers, stating, “Automatic sprinkler systems shall be installed in all parking structures” (open or enclosed). General Protection Some air-aspirating smoke detection has the ability to sense the “off-gassing” from a lithium- ion battery. This type of detection could prove particularly useful for lithiumion battery storage areas within a building. Currently, it is less favorable for use within parking garages due to the likelihood of false positives from the carbon monoxide present in car exhaust. That said, airaspirating detection is also being studied and tested for applications in actual EVs, where it may eventually be used to shunt the power to the vehicles if the batteries begin to off-gas. Finally, there are a host of simple architectural considerations to keep in mind regarding lithium-ion battery safety. At a minimum, charging and/or parking stations for EVs, including electric bikes, should be located away from the building’s means of egress. This design recommendation can have a huge impact when it comes to ensuring safety of users of lithium-ion battery devices as well as the building occupants.

Image 2: EV Charging Station


Lithium-ion Devices Dos and Don’ts • Do store devices in a safe manner. • Do purchase reputable (UL listed) batteries. • Do not leave devices unattended while charging. • Do not use damaged equipment or devices. • Do use the correct charging cord.


Jerry Manavalan, Senior Electrical Engineer, has been named among this year’s Consulting-Specifying Engineer’s 40 Under 40. This list recognizes forty engineers under the age of forty who demonstrate incomparable determination, creativity, and commitment to improve their industry and their communities. Visit Consulting-Specifying Engineer’s website to learn why Jerry is so deserving of this honor.

Project Highlight — Cornell University, McGraw Hall This historic Ithaca stone building spans four floors and consists of approximately 60, 000 square feet. Designed by architect Archimedes N. Russell and opened in 1872, the building was subsequently the subject of several ad-hoc renovations over the years, none doing justice to the formidable yet elegant structure. Fortunately, the university recently decided to embark on an exterior preservation and a much needed, comprehensive interior renovation including structure, layout, and building systems. We are delighted to be collaborating with Beyer Blinder Belle Architects and Planners on this project. When completed in 2027, the renovated building will incorporate five occupied levels. Students and faculty alike are looking forward to occupying the enhanced facility which will finally be conducive to conducting modern research and teaching within contemporary classrooms, collaborative workspaces, and updated offices. Author Credits Mechanical Considerations for Partial Renovation Projects, Gabriella Borea and Kaitlyn Nelson, Project Engineers Lithium-ion Batteries and the Implications for Fire Protection, Kevin Czarnecki, Senior Associate Getting Up-to-Speed on Connecticut Plumbing Codes, Jonathan P. Kurtz, CPD, Senior Associate Figure & Image Credits Figures and Images are courtesy of Kohler Ronan, LLC unless otherwise indicated. Image 2: License Fees Rise for Hybrid and Electric Cars in Washington. [Image]. Retrieved May, 2023 from https://www.heraldnet.com/news/car-tabs-rise-for-137000-hybrid-andelectric-cars-in-washington/

About the Firm From our offices in Danbury, Connecticut, and New York, New York, our diverse team of approximately 70 professionals collaborates with prominent architectural firms on a wide array of regional and nationally recognized project assignments. Commissions include those for world-renowned museums, fine and performing arts centers, prestigious universities, state-of-the-art educational and healthcare facilities, luxury residences, premier recreation establishments, and collaborative work spaces and ever-changing corporate campuses. Additionally, we have the privilege of designing specialty systems for landmark sites and historically significant buildings across the country. Regardless of project type, sustainability and environmentally responsible, forward-looking design are at the center of our work. For more information, please visit our website at kohlerronan.com or connect with us on social media.


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Getting Up-to-Speed on Connecticut Plumbing Codes

The 2022 Connecticut State Building Code (2021 ICC codes with Connecticut Amendments) applies to projects with permit applications filed from October 1, 2022. This article, while not providing a comprehensive list of amendments, will highlight certain key items and changes to the 2021 International Plumbing Code as amended by the 2022 CT Building Code. Engineers and designers should be sure to review all applicable codes and standards, noting that early coordination of space and routing with the architect may be necessary. Please note that “Amd” will refer to amendment. Chapter 1 – Scope and Administration (Add) 101.2.1 Gas. The International Fuel Gas Code is not adopted by the State of Connecticut. Any references to the International Fuel Gas Code within the body of this code shall be considered references to requirements of NFPA 2, Hydrogen Technologies Code; NFPA 54, National Fuel Gas Code; and NFPA 58, Liquefied Petroleum Gas Code as adopted in the 2022 Connecticut State Fire Safety and the Connecticut State Fire Prevention Codes. These requirements apply to gas piping systems extending from the point of delivery to the inlet connections of appliances, liquid petroleum storage systems, the installation and operation of residential and commercial gas appliances, and related accessories as covered by this code. Chapter 2 – Definitions (Amd) CLEANOUT. An access opening in the drainage system utilized for the removal of obstructions. Types of cleanouts include a removable plug or cap, and a removable fixture or fixture trap. Floor drains, floor sinks, mop sinks, and roof drains are not acceptable cleanouts.

Chapter 4 – Fixtures, Faucets, and Fixture Fittings (Amd) 410.4 Substitution. Where restaurants provide drinking water in a container free of charge, drinking fountains shall not be required in those restaurants. In other occupancies permanently installed bottle filling stations may be substituted for up to 2/3rds of the required drinking fountains. The bottle filling station shall be installed in accordance with ICC/ANSI A117.1. (Add) 413.5 Connection Required. Floor drains shall connect to the sanitary sewer system or to an on-site holding tank(s) when the discharge contains petroleumbased oil, grease, sand or other harmful or hazardous substances. Interceptors and separators shall be provided in accordance with Section 1003 when floor drains connect to the sanitary sewer system and shall be installed in accordance with regulations promulgated by the Department of Energy and Environmental Protection. Floor drains shall not be connected to a storm sewer, a storm drainage system, or a storm building drain. Floor drains shall have trap seals in accordance with Section 1002.4. Chapter 5 – Water Heaters (Amd) 504.6 Requirements for Discharge Piping. Amend item 10. as follows: 10. Terminate not more than 6 inches (152 mm) above and not less than two times the discharge pipe diameter above the floor or flood level rim of the waste receptor and cut at a 45-degree angle. (Amd) 708.1.1 Horizontal Drains and Building Drains. Horizontal drainage pipes, including horizontal branch drains consisting of one or more fixtures, in buildings shall have cleanouts located at intervals of not more than


100 feet (30,480 mm). Building drains shall have cleanouts located at intervals of not more than 100 feet (30,480 mm) except where manholes are used instead of cleanouts; the manholes shall be located at intervals of not more than 400 feet (122 m). The interval length shall be measured from the cleanout or manhole opening (along the developed length of the piping to the next drainage fitting providing access for cleaning), the end of the horizontal drain, or the end of the building drain. Exception: Horizontal fixture drain piping serving a non-removable trap shall not be required to have a cleanout for the section of piping between the trap and the connection to a horizontal or vertical drain if located within 4 feet (1219 mm) of developed length of such connection. The 4 feet (1219 mm) shall be measured from the fixture trap weir to the connection at the horizontal or vertical piping. Chapter 9 – Vents (Amd) 903.1.1 Roof Extension Unprotected. Open vent pipes that extend through a roof shall be terminated not less than 12 inches above the roof. Chapter 11 – Storm Drainage (Amd) 1106.1 General. The size of the components of the primary drainage system, including vertical conductors and leaders, building storm drains, building storm sewers, and any horizontal branches of such drains or sewers shall be based on the 100-year/1-hour duration rainfall rate and shall be 3.0 inches. The size of the components for the secondary (emergency overflow) roof drainage system and scuppers shall be based on twice the 100-year/1-hour duration rainfall rate and shall be 6.0 inches.

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