Consulting-Specifying Engineer • JULY 2017 www.csemag.com12

CSE: What’s the No. 1 trend you see today in the design of multifamily dwell-ings and mixed-use buildings?

Brian Berg: We’re seeing a lot of large com-plexes taking the “mixed” part of mixed-use to the extreme. Retail, restaurants, offices, hotel, residential, grocery stores, and parking are typically being built as part of one large complex. Oftentimes, this is being done on a multilevel podium with tower(s) stacked on top. And sometimes all those uses are in one tower. Parking is either all underground or a combination of underground and wrap-style lots where residential units line up around the aboveground parking. These are all being built in either dense urban areas or less dense burgeoning areas near an abundance of pub-lic transportation options.

David Crutchfield: One interesting trend we are seeing is a desire for mixed-use spaces to support lifestyle activities. For example, occupants often want an in-house gym or space for outdoor activities. We’re also see-ing an increasing number of people working or studying from home, so they need flex-ible mixed-use spaces that can accommodate their lifestyle. Overall, this indicates a larger movement toward people becoming increas-ingly reliant on their homes or dorms to cater to all their needs underneath one roof.

Kieran Healy: A growing trend we have seen within the Chicago housing market is the retrofitting of central cooling systems into low- and mid-rise multifamily build-ings that were built in the 1980s or earlier. To stay competitive with new construction,

property managers have needed to provide cooling in buildings that were often only heated with perimeter fin tubes or in-slab radiant flooring. Many owners have opted for water-source heat pumps or variable refriger-ant flow (VRF) systems to reduce the overall energy required to both heat and cool the building. These systems are unique in that a vertically tiered renovation approach can be used to keep the majority of units occupied while others are being renovated.

Lui Tai: In Ontario, the recent trend is to install automatic sprinkler protection in mul-tifamily-dwelling units, such as retirement and care homes. After a few high-profile inci-dents in retirement and care homes from the last decade where there were reported fatali-ties, the fire code is mandating that these types of buildings be reviewed to comply with the retrofit code. Within the retrofit code, there is the mandatory requirement that all such multifamily homes be retrofitted with automatic sprinklers by the year 2019.

Robert J. Voth: Amenities remain a highly attractive part of the development as compe-tition for occupants is intensifying in mar-kets outside of New York City. Additionally, mixed-use developments are moving to a smaller-scale, very efficient build model.

CSE: What other trends should engi-neers be on the lookout regarding such projects in the near future (1 to 3 years)?

Healy: Developers are becoming increas-ingly competitive with each other as they strive to capture and maintain residents in

MEP Roundtable

Brian Berg, PE, LEED AP, CEMAssociate Principal

GlumacIrvine, Calif.

Kieran Healy, PEMechanical Engineer

CCJMChicago

David Crutchfield, PEPrincipal

RMF EngineeringCharleston, S.C.

Lui Tai, PETechnical Services Director

JENSEN HUGHESToronto

Robert J. VothExecutive Vice President

Bala Consulting EngineersKing of Prussia, Pa.

Tips to design multifamily and mixed-use buildingsMultifamily dwellings and mixed-use buildings are becoming more prevalent. Some best practices and tips are offered for engineering systems in these residential buildings.

www.csemag.com Consulting-Specifying Engineer • JULY 2017 13

mixed-used facilities. Be on the look-out for more luxury amenities, such as full fitness and yoga studios, confer-ence centers with commercial kitchens, rooftop pools and spas, and lobby bars and coffee shops. Mechanical, electrical, and plumbing (MEP) systems have to be sized to allow that flexibility, supporting longer-duration occupancy of common areas versus a transient occupancy where residents are only passing through from interior to exterior and back.

Crutchfield: The infrastructure to support personal devices, such as cell phones, tablets, and laptops, for people who work from home have driven a need for higher levels of cabling and power in mixed-use buildings. Connec-tivity solutions, such as USB chargers built into receptacles and information technology (IT) wiring ready for the next level of bandwidth, are becoming standard and critical to building a mar-ketable project.

Tai: The use of alternative solutions to resolve issues that do not match the prescriptive requirements of the build-ing code. This is particularly true for new builds, but can also apply to exist-ing facilities. In new construction, alternative solutions allow more flexible designs that are not envisioned by the prescriptive code; and in existing facili-ties, they allow less destructive work to take place.

Voth: Suburban markets centered around multi-use “villages” will remain a strong market. Engineering firms will need to understand the 4-story stick-built-over-concrete development model to remain competitive.

Berg: These complexes seem to be getting bigger and more prevalent. California has a housing shortage right now, so housing is popping up all over the place with multifamily mixed-use projects as the developments of choice. This is what we see locally, but we have projects throughout the state and coun-try of similar types.

CSE: Please describe a recent project you’ve worked on—share details about the project including location, sys-tems engineered, team involved, etc.

Tai: Recently, we took on a project to design and install automatic sprinklers into 75 existing retirement-home facilities across Canada (for one owner). Because it is a retrofit proj-ect, the level of difficulty was increased. We had to come up with innovative engineering methods to do the work that would cause only minimal impact to existing residents and deal with possible asbestos issues, disease outbreak, and inadequate water sup-plies. To avoid costly errors and delays, we worked with a procurement company to schedule and administer the work, completing the $55 million project within 18 months to the satisfaction of the owner.

Voth: The Bridge in Philadelphia is an efficient 17-story building with 146 apartments. The project used a VRF system and central domestic hot-water generation to obtain U.S. Green Build-ing Council LEED certification. The team included the build partner from the beginning of the project, which led to a very efficient design and build pro-cess. Time to market was less than 20 months.

Healy: The Fannie Emanuel Senior Apartments is a 20-story senior-living facility with 181 single-bedroom apart-ments owned by the Chicago Housing Authority (CHA) in Chicago’s West Garfield Park neighborhood. As part of a $61 million gut-rehab project, we worked with Holabird & Root as the

architect and Old Veteran Construction as construction manager to completely redevelop the 132,000-sq-ft building on a 2.5-acre site originally constructed in 1963. As the MEP/fire protection (MEP/FP) engineer for the project, we selected systems to increase comfort and acces-sibility for senior citizens and brought fire alarm and sprinkler systems up to current code. HVAC systems includ-ed a 276-ton air-cooled heat pump VRF system with ducted evaporators,

Figure 1: Bala engineers provided services for The Bridge in Philadelphia, a highly efficient, 17-story building featuring 146 apartments. It incorporated a VRF system and central domestic hot-water generation to obtain LEED certification. The team worked to include the build partner from the beginning of the project to help boost the efficiency of the design and build process; time to market was less than 20 months. Courtesy: Rendering by Volley

Consulting-Specifying Engineer • JULY 2017 www.csemag.com14

MEP Roundtable

condensing boilers with panel radia-tors as supplemental heat, dedicated outside-air system (DOAS) with energy recovery for corridor make-up air and toilet exhaust, and demand-controlled ventilation (DCV) system for 1st-floor offices and community spaces. Plumb-ing systems included new condensing-water heaters, intelligent domestic booster pump, and low-flow plumbing fixtures. Electrical upgrades included new 4,000-A switchgear and metered distribution, video surveillance and IT infrastructure, LED lighting fixtures, and a 350-kW generator for life safety and standby loads.

Crutchfield: RMF Engineering was the MEP engineer for the Coastal Carolina University Student Housing project in Conway, S.C. The complex consisted of 333,100 sq ft and 1,270 beds in a series of stand-alone buildings. This project

used DOAS to provide code-required ventilation air and building make-up air. Fan coils with heating and cooling coils are provided in the rooms to allow for individual room climate control. In addition to the dorm rooms, community spaces were provided on each floor at a ratio of two large community spaces, one quiet student room, and one living room per 35 residences. Wireless and wired internet connectivity, access control and security systems, high-efficiency laundry machines, a convenience store and student cooking kitchen, custodial and maintenance storage, apartments for live-in staff, administrative offices, and reception and meeting space were all included in the buildings. Outdoor spaces incorporated sand volleyball courts, a covered pavilion complete with a fireplace, a grilling area, and plenty of courtyard green space.

Berg: We’re working on a high-rise project in downtown Sacramento, Calif., that’s wrapping up construction at the moment. The project has two levels of underground parking; four podium levels of retail, restaurants, and offices; and a 12-story tower with hotel and residential units on top of the podium. We selected a condenser-water system to serve multiple types of water-cooled HVAC equipment to suit the occupancy use.

CSE: What are some unique ele-ments/considerations to designing/retrofitting multifamily dwellings and mixed-use buildings?

Voth: The existing building floor plate is key, as the configuration for an effi-cient unit layout will drive the develop-ment opportunity. We have typically engineered all new systems in our retro-fit projects; therefore, incoming services need to be reviewed carefully, especially the domestic water, sanitary, and gas services, as residential projects demand a higher usage for these services.

Berg: There are always living spaces nearby where we want to put equip-

ment. Acoustics become a big issue in the HVAC world, but we need to be extra conscious of equipment selections, locations, and acoustic- and vibration-mitigation measures with living quarters throughout. Make sure there is always an acoustical engineer on the design team for these types of projects to help inform the MEP designs. Architects and developers often want to move the emergency generator to the roof so it is out of the public’s view and/or kept out of subterranean parking to allow for more spaces. Moving a generator out of the garage would also help lessen HVAC costs to get radiator exhaust and engine exhaust out of the building. Locating on the roof causes its own set of challenges, necessitating fuel day tanks, rated shafts for the fuel lines, and an expensive float-ing slab to deal with vibrations during generator exercising if it’s located on top of living spaces.

Tai: For retrofit projects of multi-family-dwelling buildings, the biggest consideration is to minimize impact to existing residents. This includes the design, which would require the least amount of work done within each dwelling unit and the most work done in common areas. Detailed to-the-hour scheduling is required on a daily basis to ensure that any work required within residents’ spaces are completed, so residents can return to their units as scheduled. In a senior-living environ-ment, infection control is another major consideration.

CSE: Is your team using BIM in conjunction with the architects, trades, and owners to design a proj-ect? Describe an instance in which you’ve turned over the BIM model to the owner for long-term operations and maintenance.

Healy: Our experience on numerous projects has been that the design model was not shared with the construction team. Whether for design-liability reasons or otherwise, we just haven’t

Figure 2: Engineers specified a sprin-kler in a project involving multifamily residences incorporating a combination of steel and chlorinated polyvinyl chlo-ride (CPVC) pipes. Courtesy: JENSEN HUGHES

www.csemag.com Consulting-Specifying Engineer • JULY 2017 15

seen the logical extension of sharing the design model with contractors nor have we had clients requiring this in conventional design-bid-build projects. This may change in design-build proj-ects where the designer and the builder have a contractual relationship that may offset liability concerns.

Voth: All of our projects are delivered in BIM. To date, we have not turned a BIM model over to an owner in the mixed-use market space, we have turned BIM models over in our corporate and higher education projects. We have typi-cally taken the BIM model to LOD400 and then turned it over to the contractor for the construction period.

Crutchfield: BIM has become the nor-mal tool in the design of all buildings. RMF has not delivered a job in CAD in about 18 months. The next step in pull-ing the most functionality out of BIM is getting the long-term facility staff to use the model as a tool in the operation of the facility. A cultural shift is slowly unfold-ing in which the facilities staff is outfitted with the devices necessary to access and use a BIM model. We suggest that each project’s closeout materials be provided on an Apple iPad or laptop that is pre-loaded with the BIM model and neces-sary maintenance-scheduling software. We have noticed that if we don’t drive the transfer of technology this way, the facility staff will print a set of drawings as they’ve always done in the past. If there is a paper set of drawings on the site, the electronic documents may never be accessed again.

Tai: Traditionally, sprinkler designs are completed using more special-ized software, such as HydraCAD and SprinkCAD. We are watching the trend in using BIM closely and have switched to AutoSprink, which is a software spe-cially made for sprinkler design in 3-D and is compatible with other BIM draw-ings created in 3-D. At the end of the project, the 3-D model showing the con-trol valves and pump controls are turned over to the owner(s) to allow them to visually prepare for the required peri-odic inspections.

CSE: What are some of the chal-lenges incorporating the IoT into facility design for existing build-ings?

Healy: The IoT is, in theory, a great concept. Personally, I’ve adopted all sorts of gizmos and gadgets that adjust themselves based on whether I’m home or not, or that send me text messages when my laundry is done. In owned properties, the owner has complete control over security and who has access to settings and data. A chal-

lenge in incorporating the IoT into multitenant facility design is imple-menting it in such a way that privacy and security isn’t compromised for the tenants. Maintaining firewalls for network security infrastructure and personal privacy within multitenant facilities will be a major roadblock in implementing these technologies on a larger scale.

Tai: For existing facilities, having a fully addressable system would sometimes mean complete replace-ment of field wiring, as the type and condition of existing wiring is not compatible for addressable circuits. Because the previously embedded conduit and wire cannot be reused, running new wiring throughout the building can be costly and may create unsightly conduits in open spaces.

CSE: When working on monitoring and control systems in multifamily dwellings and mixed-use buildings, what factors do you consider?

Voth: Primarily, central system reli-ability and performance; we typically do not reach into the occupant level of con-trol. We are seeing a trend to submeter domestic water usage through the con-trol systems. On higher-end work using four pipe fan coil systems, we are using the central control and monitoring sys-tem to submeter energy usage for chilled and hot water.

Crutchfield: We always try to keep in mind that the staff charged with the maintenance and control of a facility could be any age and could operate at a variety of skill levels. There could be staff members who are fresh from a trade school where they were trained with an iPad and, therefore, have no desire for paper sets of drawings or operations and maintenance (O&M) manuals. Or, there could be more sea-soned staff members who have worked on buildings for their entire careers and have no desire to use any device other than their personal cell phone and a stack of manuals. Knowing that our systems must be easy to maintain by either type of person, using vastly different methods of troubleshooting, diagnosis, and repair is imperative to having a building that functions prop-erly.

Berg: There’s a lot of submetering involved to charge tenants for the ener-gy they use. On the HVAC side, these larger projects typically all involve some sort of central utility plant, and there’s a need for British thermal unit meters for condenser, chilled, or hot water to charge the tenants appropriately. We’ve worked with special submetering com-panies to set up a system of monitoring and billing the tenants for the energy they use. We’ve also set up all of the sub-metering through the building’s direct digital control system that the building owner uses to generate the tenant billing

$2,085,000: Average total annual dollar amount

of fire and life safety systems

specified for new and existing

engineered multidwelling build-

ings, retail complexes, and/or

restaurants. Courtesy: Consulting-

Specifying Engineer 2016 Fire and

Life Safety Study

Consulting-Specifying Engineer • JULY 2017 www.csemag.com16

MEP Roundtable

themselves. It all comes down to how the operator would like to handle their billing. So, we’ll make sure we have that conversation with the operator early in the project to identify the desire and design appropriately.

Tai: For retirement and care homes, we must take flexibility into consider-ation when designing fire alarm sys-tems. For example, smoke-detector sen-sitivity and fire alarm audibility must be field-adjustable to allow changes to be made based on each tenant’s liv-ing habits. As an example, for a tenant who is always baking, the smoke detec-tor installed near the kitchen must be adjusted so that it does not always go into nuisance alarm every time the oven is opened.

CSE: Please explain some of the codes, standards, and guidelines you use during the design process. Which codes/standards should engineers be most aware of in their design of engineered systems in such projects?

Healy: When designing projects with-in Chicago, the Chicago Energy Con-servation Code 2015 (CECC, which is a localized version of the International Energy Conservation Code; IECC) often plays a big role when deciding the type of engineered systems to use or which features must be included in a system. When using the CECC or IECC, engi-neers should generally be well-versed in the exceptions that may apply to their project to avoid specifying unnecessary equipment that may add unneeded cost and operational complexity to a project.

Tai: In Canada, national building codes and fire codes are sometimes adapted by provinces and made into provincial building and fire codes. For life safety system designs, the codes would reference other applicable Cana-dian and international standards. Typi-cally, fire alarm designs are governed by UL of Canada; standards and sprinkler designs reference NFPA standards.

Berg: As energy codes get more aggressive, ensure that initial and ongo-ing code-compliance calculations are

performed to help inform the architect of envelope limitations and what impact desired envelope designs have on the mechanical and lighting systems. The additional costs of some of the needed, premium MEP systems to achieve a cer-tain envelope design could be enough for the architect to rethink glazing perfor-mance or design to remain within budget. This comes up time and again on these large mixed-use projects, and we make sure we’re always keeping an eye on the energy component from the conceptual phase on through design. We’ll maintain constant communication with the archi-tect on where the building stands with regards to energy compliance.

CSE: What are some solutions/best practices to ensure that mul-tifamily dwellings and mixed-use buildings are in compliance with codes and standards?

Berg: Have a code consultant on board early, meet in person with city and fire officials to get important deci-sions made and understood by all par-ties, and document everything.

Healy: One solution is to include an integrated MEP coordination sheet at the front of the MEP drawings where all equipment requiring building utilities are scheduled with their spe-cific utility requirements. This table ensures the designers and contrac-tors know what disciplines need, to make sure they are including neces-sary services to all applicable equip-ment. This sheet also can highlight the applicable codes that may have an impact on the design of those equip-ment. Care should be taken to avoid duplication and potential ensuing conflicts between the drawings and specifications if one changes and the other isn’t revised. However, there can also be references to the applicable specification sections for each piece of equipment to ensure the correct codes and standards references are followed without duplication.

Figure 3: The Coastal Carolina University Student Housing project involved 333,100 sq ft of facility, accommodating a total of 1,270 beds in a series of stand-alone build-ings. Features specified by RMF Engineering’s team included dedicated outdoor units that provide code-required ventilation air and building make-up air including fan coils with heating and cooling coils, allowing for individual room climate control, wireless and hard-wired internet connectivity, access control and security systems, high-efficiency laundry machines, and more. Courtesy: RMF Engineering

Tai: For every jurisdiction, it is impor-tant to know the applicable code thatapplies to the multifamily dwellingsand mixed-use buildings. For example,in Ontario, the retrofit requirement fora retirement home would differ fromthat for a residential rental building.Authorities often overstep their author-ity by requesting changes that are notretroactively applied to some existing

buildings. If in doubt, always consultwith a code consultant.

CSE: How are codes, standards,or guidelines for energy efficiencyimpacting the design of such build-ings?

Tai: Energy efficiency is now part ofthe building code requirement in Ontar-io. Even though it has not yet made a sig-nificant impact to our design, the trendis definitely moving toward achievingit. For example, LED visual strobes willsoon replace the traditional high-inten-sity strobes, which draw a lot of power.This will, in turn, demand smallerpower supplies and smaller gauge fieldwiring, leaving a much smaller ecologi-cal footprint.

Berg: Higher-performing envelopesand higher-performing HVAC andlighting systems are being implemented

to meet current energy codes. Architectsare still designing many predominantlyglass buildings because the market reallydemands it at the moment, but that glaz-ing is high-performing, the accompany-ing HVAC systems are extremely effi-cient, and the connected lighting loadsand lighting controls are aggressive.

CSE: What new code or standarddo you feel will most impact mul-tifamily dwellings and mixed-usebuildings? This may be a code thatyour authority having jurisdiction(AHJ) has not yet adopted, but youfeel will directly impact your work.

Berg: Three-story and less multi-family new-construction buildings inCalifornia will need to be designed tonet zero energy standards starting in2020. That’s the next code cycle, butmany developers are not fully aware of

MEP Roundtable

81% of engineers most

frequently write performance fire

and life safety system specifica-

tions for engineered multidwelling

buildings, retail complexes, and/or

restaurants. Courtesy: Consulting-

Specifying Engineer 2016 Fire and

Life Safety Study

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input #9 at www.csemag.com/information

the requirements, so education needs to occur with all parties in the market-place.

Healy: With recent changes to the LEED v4 rating system, more prop-erty owners will begin pursuing LEED ratings for buildings that are 4 stories and higher, leading to different design approaches than what currently occur. The added flexibility in selecting wheth-er to use the Multifamily Midrise or the New Construction rating system will reduce some of the past issues that made multifamily certifications extremely costly for owners and difficult to design for architects and engineers.

Tai: With the increase in hybrid or electrical vehicles on the road, a new code requirement might be added for charging stations inside the garage for multifamily and mixed-use dwelling buildings. There is still a lot of work to be done to standardize the charg-

ing requirement between the many automobile manufacturers, however, before the building code can request that charging stations be provided in these multifamily-dwelling buildings.

CSE: What are some of the chal-lenges for fire and life safety system design for multifamily dwellings and mixed-use buildings? How have you overcome these challenges?

Tai: The conflicting requirements of life safety versus security always pose an interesting challenge. In a fire sce-nario, all doors must be released to allow for safe egress from the building, yet in some secured areas, keeping the doors secure is almost equally important to stop patients from wandering off in case of a nuisance alarm. We often introduce a small time delay into the release of a secured door, which would allow staff

members of a nursing home to confirm the fire condition and then be present at this unsecured door to attend to the needs of those in evacuation.

Berg: Space is always tight and valu-able for high-rise multifamily build-ings, so it’s often a challenge squeezing in smoke exhaust and smoke-exhaust make-up air shafts. We’ll often use a make-up air shaft for double-duty and provide space conditioning during nor-mal operation through the same shaft.

CSE: Describe the cost and com-plexity of fire protection systems involved with such structures. Have they changed over the years?

Voth: Fire protection systems have dramatically changed when structures exceed 340 ft in height. Current tech-niques include a spare high-zone fire pump and secondary-water street service.

input #10 at www.csemag.com/information

20 Consulting-Specifying Engineer • JULY 2017 www.csemag.com

Depending on the regional AHJ, storage tanks for fire protection systems may be required at the top of the building.

Tai: The cost of the intelligent con-trol systems for the multifamily dwell-ing and mixed-use building has gone up because of the sophisticated computing power of the control panels. However, hardware cost for field wiring is reduced due to the programmability of the sys-tem components. Overall, the cost of the fire protection system is only increased marginally over the years. The notice-able increase in cost comes from the requirement that all sleeping rooms must be equipped with visual signaling devices.

CSE: In supertall, high-rise mul-tifamily dwellings and mixed-use buildings, what types of areas of ref-uge, elevator egress, or other solu-tions have you implemented?

Tai: In a typical high-rise building, smoke detectors are designed into every elevator lobby to allow eleva-tors to return home on any fire condi-tion. The smoke detector installed on the home floor will send the elevators to their alternative home floor. In a supertall, high-rise building, occu-pants cannot use the stairs to exit the

facility, thus must use the “egress eleva-tors.” Designated egress elevators are installed in a 4-hour-rated shaft, with designated stops (i.e., every 10 or 15 stories) along the way, which are con-structed as fire-rated and pressurized spaces. The elevator call button in these designated stops are connected to the smoke detector in the corre-sponding elevator lobby, which would stop the egress elevator from stopping on this floor should the smoke detector be activated.

Voth: We are engineering dedicated firefighter wireless communication systems in all of our supertall struc-tures; egress stairways are now suffi-cient to let firefighters into the build-ing while providing an egress path for occupants.

CSE: What unique HVAC require-ments do multifamily dwellings and mixed-use buildings have that you wouldn’t encounter in other build-ings?

Healy: Once of the biggest dif-ferences in multifamily residential buildings with owned units (condo-miniums) versus other types of rental and commercial buildings is ensuring that all systems for each unit are locally

powered and accessible and under the control of the unit owner. Due to the relatively small size of these units, the HVAC equipment serving these units are fairly small and generally not too efficient, and there’s no coordination between units to allow diversity and central system economies of scale.

Berg: We tend to end up with multi-ple system types to suit the occupancy. I’m working on a mixed-use building right now with a condenser-water sys-tem serving multiple types of mechani-cal units. We have water-source heat pumps for the residential floors and podium retail, water-cooled VRF for hotel floors, vertical self-contained water-cooled variable air volume for office floors, and radiant in the lobby areas that gets hot water and chilled water produced by water-cooled VRF systems.

CSE: Have you specified VRF sys-tems, chilled beams, or other types of HVAC systems into one of your multifamily dwellings and mixed-use buildings? If so, describe its chal-lenges and solutions.

Berg: We’ve used VRF on some mixed-use buildings, typically for hotel occupancies, but not for residential. The preference of splitting up utili-ties between residential tenants usu-ally steers us toward water-source heat pumps or chilled-water fan coil units to more easily submeter energy usage via British thermal unit meters.

Voth: We see a significant move toward VRF in many of our multifam-ily projects, especially when LEED cer-tification is an objective. We typically do not use chilled beams in any proj-ects that include operable windows, as the beams will sweat.

Healy: One of the biggest challenges in implementing a large-scale VRF sys-tem for a multifamily complex is man-aging refrigerant loss that may occur from the small pipe sizes and magni-tude of fittings required to distribute

MEP Roundtable

Figure 4: According to a recent research study, LEDs are the No. 1 product specified in multidwelling/retail complexes/restaurants. Courtesy: Consulting-Specifying Engi-neer 2017 Lighting and Lighting Controls Study

Figure 4: According to a recent research study, LEDs are the No. 1 product specified

Top 3 lights, lighting products used in engineeredmultidwelling/retail complexes/restaurants

LEDs Lighting controls, addressable systems

T5, T8, orT12 (any size)

95%

73%59%

T5 T8 or

59%

Lighting controls

73%73%

LEDs

95%

refrigerant throughout a large footprint. While investigating existing installations, our firm has come upon VRF instal-lations that were losing more than 100% refrigerant charge each year. Consider installing refrigerant-monitoring sys-tems in shafts or other areas where fittings may be concealed, installing valves at branch controllers to isolate zones, and using continuous-refrigerant line sets between branch con-trollers and terminal units to reduce the likelihood of leak points being buried within walls or ceilings. Refrigerant piping will inevitably leak over time; make sure the design solution will allow a property manager to find and seal those leaks easily.

CSE: What types of DOAS are owners and facility managers requesting to keep their facility air fresh?

Voth: As a standard of practice, we use a DOAS with heat recovery including latent heat recovery on all of our projects. We have been powering the relief fans on emer-gency power to eliminate the need for fire/smoke damp-ers throughout the building risers. We document subduct connections in lieu of fire smoke dampers when the relief fan is on emergency power.

Healy: For multifamily dwellings, facility managers have often requested variable-volume DOAS with energy-recovery plates. This allows them to reduce airflow when not needed and recover energy between code-required toilet exhaust and corridor make-up airstreams. For mixed-used facilities, systems with DCV are often requested for commercial areas to account for occupant loads using carbon dioxide sensors. Facility managers are able to account for commercial vacancies and varying occupancy throughout the day and week.

CSE: What unusual systems are owners requesting that help save energy and/or electricity when a space is unoccupied?

Tai: We have received a unique request from a building owner who wants to have occupancy sensors on all exit lights, such that the exit signs will turn off when the room is unoccupied.

Berg: We’ve used key cards in hotel rooms to shut off lights and HVAC. We’ve used occupancy sensors to reset outside-air quantities and temperature setpoints. Demand-control ventilation is pretty common in retail and food and beverage spaces on podium levels to save energy when the customer traffic is light.

21Consulting-Specifying Engineer • JULY 2017

n Automation and controlsn Electrical and powern Integration and interoperability.

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