buildings

BACK TO THE FUTURE

Posted on by abrahamwien18

IS IT 1919 OR 2020?

By: Ted Konigsberg, President
Infinity Commercial Real Estate

AS YOU CAN SEE IN THESE OLD PHOTOS, WE’VE BEEN HERE BEFORE.

  • WHAT CHANGES TO OUR BUILDINGS AND CITIES RESULTED?
  • WHAT CHANGES CAN WE EXPECT TODAY?

After months of conference calls, Zoom videos and webinars, only now is our industry’s vision of the new physical world beginning to emerge.

If the past is prologue, we can predict the future through research of the structural changes that occurred after the Cholera Epidemics of the 1800’s the Typhoid Epidemics of the 1800’s & 1906-1907), and the Spanish Flu of 1918 -1919.

Six cholera pandemics in the 19th century cost hundreds of thousands of lives. The renovation of Paris’ and London’s infrastructures followed, as did the construction of New York’s Central Park in 1857.

Upgraded sanitation, broadened streets and open public areas. The Spanish Flu took over 50 million lives around the world. Robert Koch’s discovery of the tuberculosis bacillus in 1882, transmitted by droplets (sound familiar?) gave rise to sanitoriums, buildings designed to house, treat, and isolate patients, emphasizing strict hygiene and ample exposure to sunlight and air.

The beginning of the 20th Century gave birth to Minimalism and Modernism. Victorian décor (soft fabrics, velvet drapes and wall coverings, small rooms, carpets and rugs) where dust and germs could linger and become vectors of disease, was replaced by modern stark designs, with minimalist furniture and cleanable surfaces like tile, glass and steel. Buildings were designed to bring light and fresh air to the occupants. The visionary Swiss architect Le Corbusier designed structures that included sinks at the entrances: Today, this survives as the guest or half bath. Open terraces, roof gardens, skylights and cross ventilation became prevalent. Rooms were large, open, airy. These photos are of buildings and interiors 85 -100 years old!

Dust lodged in decorative features was the enemy of hygiene. Designers used lightweight, washable materials. Michael Thonet used bentwood and cane, Aalto used bent plywood, and Marcel Breuer and Mies van der Rohe used tubular steel. Furniture was light and easily moved for cleaning, to deprive dust, germs and insects of hiding places in the dark.

By the 1920’s air conditioning was viable and in use in buildings of public accommodation. Yet, the Empire State Building has multiple open-air decks, and single hung, OPENING windows, as do vertical buildings of the time. Light, fresh air, social distancing…

Restaurants changed too. Below is a photo of the original Lawry’s The Prime Rib, built in Los Angeles in the 1920’s. Note the banquette seating for isolation and the materials used for surfaces throughout the room, all easily cleanable.

The events of the early 1900’s impacted our collective psychology, and the effects long outlived the events themselves.

The changes in our constructed environment became the norm, but the difficult lessons were forgotten as the generations that lived through these pandemics passed. We are now compelled to relearn them.

OK, SO YOU’VE LOOKED AT SOME COOL OLD PHOTOS AND ARE TOTALLY BORED BY MY MUSINGS… WHAT DOES THE FUTURE LOOK LIKE?

  • CIVIL ENGINEERING, PLANNING: Cities will expand open areas, such as parks and streets. No car zones, which London and Paris have had for many years, will become common in shopping and entertainment districts, to allow for distancing and outdoor tables and exhibits. Expect significant upgrades to water and sanitation systems. Working from home has created huge demand for high speed internet access: Fiber optic installations, new towers for 5g. The death of the automobile has been vastly over-hyped. When will you feel safe traveling by train, bus, or subway? When will you feel safe ridesharing? So, upgrades to parking and roads, less construction of new public transportation. A return to the suburbs. Rezoning and reconfiguration of many high-density buildings, such as failed hotels and offices.
  • EXISTING VERTICAL BUILDINGS: Major upgrades to HVAC systems, such as UV lights in air handlers, HEPA filters, coil disinfectant systems. Wall sconces in hallways replaced by UV light air purifiers. Larger washrooms with hot water sinks and touchless faucets. Tile instead of carpeting. Reconfigured common areas for distancing. Rooftop gardens. Cleanable wall coverings and furniture. Touchless door systems. Voice-activated elevators.
  • NEW VERTICAL BUILDINGS: In addition to the above, opening windows, Balconies, open-air decks, and rooftop amenities, like running tracks and gardens. Wider and windowed stairwells and hallways, larger and more elevators. Perhaps a return of the atrium concept with skylights. Much larger common areas.
  • RESIDENTIAL: Do you feel safe walking through a crowded lobby, pushing buttons on an elevator with multiple people in it, passing your neighbors in the hallway? Not having access to the building gym, restaurant, or pool if there’s another outbreak in the future? Vertical condos and apartment buildings will suffer. On the lower-end, garden style apartments with their stairwells and patio or balconies will become desirable again. For larger residences, townhouses and single-family homes (sale and rent) will benefit. A fenced yard will matter. High speed internet will matter, as you will spend more time working from your “cave”. A half bath at or near the entrance will matter. A spare room separate from the main living areas with a dedicated washroom for use as your office, grown kids room, or parent’s room (will you send mom to an assisted living facility unless you have to?) will be a very desired feature, as will an entry “parlor” separated from the living areas.
  • OFFICE: A protracted decline. Companies realize their employees can effectively work from home, while reducing risk of infection and corporate liability. In high-tech industries, international employees will not have to be relocated to work in the US; software engineers can stay in Bangalore and be just as productive via VPN, WebEx and Zoom. Why apply for a Visa? An offset will be a greater amount of footage required per occupant to effect social distancing, but that won’t be enough to fully compensate the increased vacancy. The “We-Work” co-working and hoteling concept will face demise, but operators such as Regis will thrive. Rents will fall, CAP rates will rise. A shift to single story walk-in, non-CBD (suburban) property locations, much of which will be repurposed retail space and industrial/office flex buildings.
  • INLINE RETAIL: Will suffer in the short term but rebound strongly. Local services still matter. Convenience stores, liquor stores, dry cleaners, hair salons, drug and grocery stores are necessary. Expect countless neighborhood restaurant closings, but also expect “virtual” restaurants (kitchens) to emerge, as online ordering will continue. Outdoor seating will help make up for lost table density. Expect alternate types of uses, like office, medical and dental.
  • BIG BOX RETAIL: Power centers give their tenants something malls can’t: Control of their sites. Curbside pickup will continue. Further, many of these are in “last mile” locations. Think of Best Buy, which is thriving. They use their stores as distribution centers: When you order from them, chances are the item comes right from store inventory, which how they compete with Amazon on delivery. Expect to see more of this model. Amazon’s share of the total US retail market is only 3%. Walmart does 3 times the volume of Amazon, and their operations are extremely efficient and improving. Those retailers with a brand that matters to consumers, an efficient and friendly online experience and a store centric logistics model will capture market share. As to broad-line big boxes like JC Penney, Sears, Neiman-Marcus… They will continue to suffer, and possibly not survive.
  • MALLS: Only the best operators will endure. Those that do will be greatly changed. Most failed anchor stores will require complete repurposing and reconstruction. Both large and small tenants will want outward facing ingress and egress, so malls will have to face outwards, not inwards. With their large land areas, the best locations will make those changes, and attract outparcel operators. Those that survive will embrace mixed use: Residential, office, and even “last mile” logistics facilities will replace many existing tenants. Rents will fall. The short-term pain will be immense, and failed malls may be a great investment opportunity for developers.
  • HOSPITALITY: Central Business District facilities will be badly impacted. We may see numerous properties repurposed. To survive, touchless check-in and doors, expanded common areas. No significant new construction of CBD and airport properties, pure survival mode for years to come. As folks drive more and fly less, roadside motels and extended stay properties, with outdoor room entrances and kitchenettes, will thrive again. Soon, companies like Airbnb will have a resurgence, continuing to capture market share, as they offer travelers privacy and control.
  • INDUSTRIAL: The lack of supply chain reliability has become painfully evident, and as time to delivery becomes increasingly important, manufacturing will return to our shores. Even Grandma orders online now and expects everything to be delivered immediately. Manufacturers will gladly pay a little bit more to source components from a reliable US based supplier, instead of waiting a month (at best) for a “slow-boat from China”. Further, automated manufacturing depends much less on the cost of labor than the cost of electricity and real estate: Both are cheaper here than in Asia.

As retail become more reliant on fast delivery, expect “last mile” locations to excel, along with dedicated cold chain distribution facilities. Many local and regional tenants will ditch their dedicated office locations and seek out industrial flex with 20% to 40% office components, so they can reduce overall rents, control access and exposure, and feel safe. Rear loaded multi-tenant properties with curb appeal and high parking ratios are gold!

MANUFACTURING, INDUSTRIAL FLEX AND LOGISTICS WILL THRIVE.

Improving Indoor Air Quality the Easy Way

Posted on by abrahamwien18

Environmental Leader, 5/2/2014
View the original article here

The natural first step most building managers take when they suspect that their building is causing health problems is to find the root cause and remove, replace or fix the problem. However, there are often more direct and less costly ways to attack poor indoor air quality, LEED trade magazine EDC reports.

Among these ways:

  • Use fewer chemicals. Cleaning chemicals, whether green or not, impact the indoor environment and using less will, naturally, lessen the impact. Janitors and other cleaning staff are wont to mix more chemical with water than necessary, according to EDC. This can be eliminated by installing an automatic dilution system.
  • Using greener chemicals can help, too. Look for products that have been independently tested and bear ecolabels such as UL’s Ecologo or the EPA’s Design for the Environment program. These are a better bet for those wanting to buy VOC-free or low environmental-impact chemicals.
  • Check vacuum cleaners. Vacuum filters are the one piece of equipment that can most contribute to indoor air quality improvement. By selecting advanced filtration filters and changing them regularly — twice a year is usually adequate — you can make drastic improvements.
  • Train workers on green cleaning. Many custodial workers don’t use environmentally friendly products in the right way. Implementing a training plan or sending workers to a green cleaning training program can overcome this problem.
  • Educate building users. Educating all those who use the building on the best ways to improve indoor air quality is the best way of making sure all building users are playing their part.

The global revenue for the indoor air quality monitoring and management market, driven by new building standards and regulations as well as a rebounding economy, will grow 80 percent to $5.6 billion by 2020, according to a forecast from Navigant Research released earlier this week.

The developed markets for indoor air quality-related HVAC markets remain sluggish — a holdover from the 2009 global recession. However, the North American market will become more robust this year. Europe will follow a similar trend but will not begin to recover until late 2014, the report says.

10 Smart Building Myths Busted

Posted on by abrahamwien18

May 6, 2014 by Lee O’Loughlin

View the original article here

Smart buildings are a no-brainer and more affordable than most building owners and investors realize.

Smart buildings have been proven to save energy, streamline facilities management and prevent expensive equipment failures. Yet, to many property owners and investors, the value of smart buildings remains a mystery. The fact is, in most buildings, we can demonstrate a strong business case for strategic investments in smart building systems and management technologies.

Not everyone is aware that the tremendous advantages of today’s affordable smart building management technologies easily justify the cost. The following are 10 myths about smart buildings, along with the facts:

Myth #10: Smart Building Technologies Are Expensive.

Myth Debunked: Smart building technology investments typically pay for themselves within one or two years by delivering energy savings and other operational efficiencies. One smart building management pilot program we worked on, for example, generated a positive return on investment within several months.

Myth #9: Smart Buildings are Only About Energy.

Myth Debunked: A smart building management system often can detect when a piece of equipment is close to failure and alert facilities personnel to fix the problem. Knowing the right time to repair or replace equipment extends machinery life, and reduces facility staff, operations and replacement costs. More dramatically, smart building management systems can prevent full-scale building system failures—potentially embarrassing to a Superbowl stadium host, but life-threatening in a hospital or laboratory.

Myth #8: Smart Buildings and Green Buildings are the Same Thing. Myth Debunked: Smart buildings maximize energy efficiency from building systems and ensure air quality, while a complete “green” sustainability program includes strategies beyond building automation systems. So, while “smart” and “green” features may overlap, they are not identical concepts. The Continental Automated Buildings Association (CABA) explains the difference in Bright Green Buildings: Convergence of Green and Intelligent Buildings, a comprehensive report authored with Frost and Sullivan.

Myth #7: Industrial Facilities or Laboratories Can’t Become Smart Buildings.

Myth Debunked:  All types of buildings—whether residential or commercial—can be built or retrofitted to become highly automated and smart. Even highly specialized facilities such as laboratories can be outfitted with smart building technologies.

Myth #6: Smart Buildings Can Only Be New Buildings.

Myth Debunked: Some of the smartest buildings in the world are not new at all, but have demonstrated the return on investment in smart technologies. The Empire State Building, for example, has exceeded projected energy savings for the second consecutive year following an extensive phased retrofit begun in 2009.

Myth #5: Smart Building Technologies are Not Interoperable.

Myth Debunked: In the past, building automation equipment and controls were designed as proprietary systems. However, affordable new technologies, such as wireless sensors, now make it possible to gather data from disparate systems produced by any manufacturer.

Myth #4: Smart Systems Don’t Make a Building More Attractive to Tenants.

Myth Debunked:  Anything that improves energy efficiency, reduces occupancy cost and improves productivity is valuable to tenants, as numerous studies and surveys attest. Tenants and their advisors increasingly expect smart building features such as zoned HVAC, sophisticated equipment maintenance alert systems, and advanced security systems. As reported in JLL’s October 2012 Global Sustainability Perspective, smart systems provide benefits for tenants—and tenants recognize the benefits.

Myth #3: Without a Municipal Smart Grid, a Building Can’t Really Be Smart.

Myth Debunked:  It’s true that smart buildings gain functionality when supported by advanced electrical grids installed by municipalities and their utility company partners. But even without a smart grid, owners and investors can draw a wide range of benefits from smart buildings and a smart building management system that can monitor entire property portfolios.

Myth #2: Smart Buildings Are Complicated to Operate.

Myth Debunked: Combined with a smart building management system, a smart building is often easier to operate and maintain than a building that lacks automated systems. A smart building management system can integrate work-order management applications; pull equipment repair and maintenance data into performance analytics; and pinpoint equipment issues to a degree not humanly possible. For example, a smart building management system can diagnose a programming problem that has been undetected for 15 years, enabling facility managers to resolve a recurring equipment malfunction.

Myth #1: Smart Buildings Are a No-Brainer.

Myth NOT Debunked: This myth isn’t a myth at all — it’s actually true. As affordable new technologies are adopted, tenants are beginning to expect smart building features—and owners and investors are beginning to realize the return on investment in smart systems.

Leo O’Loughlin is senior vice president of Energy and Sustainability Services at JLL, the global professional services and investment management firm offering specialized services to clients that own, occupy and invest in commercial real estate. With 20 years of energy and sustainability management expertise, Leo helps clients incorporate energy and sustainability concepts into operations and project management, reducing energy consumption, utility expense and carbon emissions. He specializes in creating and analyzing project structures for energy efficiency, central utility plant and energy services outsourcing programs, managing the multi-disciplinary development of energy infrastructure assets and retrofit projects. He also manages business development, commercial structuring, financial and technical analyses and implementation of energy-related projects. Previously, Leo was an executive at several leading California energy companies. He holds an MBA from San Diego State University and a BS in mechanical engineering from Purdue University.

7 Factors Driving High Performance Buildings

Posted on by abrahamwien18

8/30/13

View the original article here

In a world faced with an evolving array of challenges – economic, environmental, security, and social – the bar for building performance is continuing to rise. High performance buildings go beyond the basic requirements of codes and standards to significantly reduce energy consumption, increase use of renewables, have a minimal environmental impact in material use and site selection, enhance human comfort and safety, and improve occupant productivity.

High performance buildings also create the flexibility necessary for open-plan space and respond efficiently to inevitable changes within the building. High performance buildings achieve these performance objectives in a cost-effective manner throughout the lifetime of a facility.

According to Legrand, a provider of infrastructure solutions, a host of factors are driving a paradigm shift in performance expectations within the built environment. Key factors include:

  1. Market and Economic Forces: In recent years, institutional investors and building owners have sought out energy and other efficiencies in building portfolios to reduce risk and improve asset value.
  2. Homeland Security & Natural Disasters: Today’s buildings are faced with a more diverse and rising number of man-made and natural threats, ranging from terrorism to flooding and earthquakes.
  3. Energy Security and Climate Change: In the United States, buildings consume nearly 40% of all national energy and significant amounts of natural resource, putting the sector under increasing pressure to become more energy and resource efficient.
  4. Social Equity: The aging of the American population and the landmark Americans with Disabilities Act are driving building owners and managers to redefine and redirect the traditional understanding of design for accessibility.
  5. Changes in Building Design, Delivery, and Management: New information management and modeling tools, such as Building Information Modeling (BIM), have created the ability to simulate and manage building performance across a wide array of attributes.
  6. Information Technology: The Internet, with all its associated devices and applications, is changing the functioning of the building and the activities of its occupants. This creates demand for new levels of embedded intelligence, communications, and interoperability of systems and products.
  7. Codes and Standards: A new generation of building codes and standards are a reflection of new market expectations, and they have become a driving force for higher levels of building performance.

The federal government formally defined high performance buildings in the Energy Independence and Security Act of 2007, but in practice, it is building owners and managers and the design teams they commission who define and embody high performance on a day-to-day basis.

Top 25 Cities with Most ENERGY STAR Buildings

Posted on by abrahamwien18

April 10, 2014
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The EPA announced the sixth annual list of the top 25 U.S. metropolitan areas with the most ENERGY STAR certified buildings. The cities on this list demonstrate the economic and environmental benefits achieved by facility owners and managers when they apply a proven approach to energy efficiency to their buildings.

The Top 10 cities on the list are: Los Angeles; Washington, D.C.; Atlanta; New York; San Francisco; Chicago; Dallas; Denver; Philadelphia; and Houston.

“Not only are the ENERGY STAR’s top 25 cities saving money on energy costs and increasing energy efficiency, but they are promoting public health by decreasing greenhouse gas emissions from commercial buildings,” said Administrator Gina McCarthy. “Every city has an important role to play in reducing emissions and carbon pollution, and increasing energy efficiency to combat the impacts of our changing climate.”

Energy use in commercial buildings accounts for 17 percent of U.S. greenhouse gas emissions at a cost of more than $100 billion per year. ENERGY SSTAR-certified office buildings cost $0.50 less per square foot to operate than average office buildings, and use nearly two times less energy per square foot than average office buildings.

The data also show that more than 23,000 buildings across America earned this certification by the end of 2013. These buildings saved more than $3.1 billion on utility bills and prevented greenhouse gas emissions equal to the annual electricity use from 2.2 million homes.

First released in 2008, the list of cities with the most ENERGY STAR-certified buildings continues to demonstrate how cities across America are embracing energy efficiency as a simple and effective way to save money and prevent pollution. Los Angeles has remained the top city since 2008 while Washington, D.C. continues to hold onto second place for the fifth consecutive year. Atlanta moved up from the number five to number three. For the first time, Philadelphia entered the top 10, ranking ninth.

Commercial buildings that earn EPA’s ENERGY STAR must perform in the top 25 percent of similar buildings nationwide and must be independently verified by a licensed professional engineer or a registered architect. These certified buildings use an average of 35 percent less energy and are responsible for 35 percent less carbon dioxide emissions than typical buildings. Many types of commercial buildings can earn the title, including office buildings, K-12 schools, hotels and retail stores.

Products, homes and buildings that earn the label prevent greenhouse gas emissions by meeting strict energy efficiency requirements set by the U.S. EPA. In 2013 alone, Americans saved an estimated $30 billion on their utility bills and prevented greenhouse gas emissions equal to the annual electricity use of more than 38 million homes with the help of ENERGY STAR. The label can now be found on products in more than 70 different categories, with more than 4.5 billion sold. More than 1.5 million new homes and 23,000 commercial buildings and industrial plants have earned the label.

The 2014 Energy Star Top Cities are:
1. Los Angeles
2. Washington, DC
3. Atlanta
4. New York
5. San Francisco
6. Chicago
7. Dallas-Fort Worth
8. Denver
9. Philadelphia
10. Houston
11. Charlotte
12. Phoenix
13. Boston
14. Seattle
15. San Diego
16. Minneapolis-St. Paul
17. Sacramento
18. Miami
19. Cincinnati
20. San Jose
21. Columbus, Ohio
22. Riverside, Calif.
23. Detroit
24. Portland, Ore.
25. Louisville

More on the 2013 top cities: www.energystar.gov/topcities

More on Energy Star certified buildings: www.energystar.gov/buildinglist

10 US cities vow to slash emissions from buildings

Posted on by abrahamwien18

By ALICIA CHANG, AP Science Writer | January 29, 2014
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LOS ANGELES (AP) — Mayors from 10 U.S. cities took aim at their skylines Wednesday, pledging to reduce greenhouse-gas emissions from their buildings.

Businesses and homes are a major source of carbon-dioxide pollution in cities, with most of it coming from the burning of fossil fuels for heating, cooling and lighting.

Many of the participating cities — Atlanta, Boston, Chicago, Denver, Houston, Kansas City, Mo., Los Angeles, Orlando, Fla., Philadelphia and Salt Lake City — already are working toward making their building stock more energy efficient.
Los Angeles last year became the first major city to require new and remodeled homes to sport “cool roofs” that reflect sunlight as part of an effort to save energy and reduce electricity bills.

Boston requires energy audits from building owners. The city, along with Chicago and Philadelphia, passed measures to track how much energy buildings are using as a first step toward boosting their efficiency.

Other places including LA, Atlanta, Denver, Chicago, Houston and Salt Lake City, participate in a voluntary federal program to cut energy waste from commercial and industrial buildings.

Under the new effort, cities will work with the Natural Resources Defense Council (NRDC) and the Institute for Market Transformation, a nonprofit that promotes green building, to continue their progress and further shrink their carbon footprints by targeting existing commercial and apartment buildings.

The groups projected the emission reductions would be equal to taking more than a million cars off the road, and they could save residents and businesses $1 billion annually. The project is funded by ex-New York City Mayor Michael Bloomberg’s foundation and other philanthropic groups, which invested $9 million for three years.

New York City managed to cut its emissions by persuading some landlords to switch from oil to natural gas, Bloomberg said.

Los Angeles Mayor Eric Garcetti said cities can be the matchmaker between building owners and banks that lend money for energy-efficient upgrades. He said greening buildings makes economic sense.

“We look forward to stealing your best ideas,” he told other mayors.

The cities were chosen for their geographic diversity, ambitions and ability to follow through, said project director Laurie Kerr of the NRDC.

The cities will craft their plans in the next several months. Backers acknowledged that some policies may require legislation. It’ll take several years to gauge whether cities met their emissions and savings goals.

Keith Crane, director of the environment, energy and economic development program at the Rand Corp. think tank, called the partnership a good first step. But he doesn’t consider it earth-shaking.

“It’ll have a modest effect on greenhouse gas emissions if everything goes right,” he said.

Right-Size Your Ventilation Needs

Posted on by abrahamwien18

Learn how demand control ventilation can reduce energy use

By Jennie Morton
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Can ventilation requirements and energy conservation go hand in hand? They can if you implement demand control ventilation (DCV).

There’s no reason to waste energy conditioning air for people who aren’t in your building. Instead of supplying air at fixed rates, DCV automatically adjusts ventilation levels based on real-time occupancy measurements. This strategy allows you to meet code and reduce energy use without sacrificing indoor air quality.

EXHAUST YOUR OPTIONS
The problem with traditional ventilation is that it cannot distinguish between actual vs. projected occupancy. As outlined in ASHRAE 62.1-2013, Ventilation for Acceptable Indoor Air Quality, ventilation rates are calculated using two factors: square footage and peak occupancy.

Since square footage is a constant, any fluctuations on the occupancy side of the equation give rise to energy waste. With travel, sick days, vacation, and inclement weather, your building is rarely at capacity. In fact, human resources data shows an average of 75% of workers will be in attendance at any given time.

Without a way to calculate the actual headcount, your HVAC system operates as if maximum occupancy occurs on a continuous basis. If you can eliminate the excess air supply whenever fewer people are present, however, you have an opportunity to capture energy savings.

To have a responsive, intelligent HVAC system, you need to implement demand control ventilation. This strategy recognizes when a space has fewer people than scheduled and drops ventilation levels accordingly, explains Daniel Nall, senior vice president with Thornton Tomasetti, an engineering firm. Air supply is calculated using verified headcounts rather than occupancy projections. DCV is no different than using occupancy sensors to control lights – both ensure energy is conserved when there’s no activity in a space that justifies its use.

For example, offices need to supply 5 cubic feet per minute (cfm) per person in addition to a baseline of 0.06 cfm per square foot, Nall explains. Unoccupied, a 250-square-foot office needs 15 cfm to meet the ASHRAE standard. With one individual present, this increases to 20 cfm. Using DCV to sense when the room is empty, you can scale back the ventilation from 20 to 15 cfm, a 25% decrease in air supply. These savings are then multiplied across any room that has DCV capability.

If your occupancy variations are known in advance, DCV may be as simple as using a basic schedule in a building management system, says Jules C. Nohra, manager for energy efficiency at SourceOne, an energy consulting and management firm. Those with irregular or unforeseen occupancy fluctuations, however, will require sensors that can determine how many people are present. These include education, retail, conference areas, performance venues, lobbies, and offices with a mobile workforce or flex hours.

Carbon dioxide monitoring is by far the most common way to determine occupancy, says Thomas Lawrence, senior public service associate with the College of Engineering at the University of Georgia. The technology is well-established and straightforward to implement. CO2 isn’t treated as a contaminant that needs to have its levels controlled (a common misconception), but as a representation for the number of bodies in a space.

“Carbon dioxide measurements act as a surrogate for occupancy because humans generate an average volume per hour,” explains Nall. “By calculating the concentration differential between internal CO2 volumes and the outside air, you can estimate the number of people in your building. For example, if your CO2 concentration doubles, then occupancy has doubled.”

Occupancy sensors, such as the infrared ones you pair with lighting controls, can also be used. These are the most effective in individual work spaces and private offices, Lawrence observes. For a zone with multiple workers, however, they don’t offer fine enough measurements to calculate total attendance.

For example, think of an open floor plan that houses 30 people. The occupancy sensor will trip when the first person arrives, but it can’t scan the room an hour later to see if all 30 workers showed up that day. It also can’t detect if 15 of those employees move to another part of the building for a two-hour meeting, leaving the space over-ventilated during that period.

Entertainment venues may be able to use ticket sales to confirm a headcount. Other facilities can derive occupancy by counting cell phone signals present in the facility, Lawrence says. It’s also possible to have IT report the number of active computers, assuming that each device fired up represents a person in the space. If you use an access control system and it can interface with your BAS, each card swipe, keypad entry, or turnstile rotation can count toward occupancy.

INSTALL WITH AN AIR OF CONFIDENCE
Integrating demand control ventilation is heavily influenced by your existing HVAC system, such as whether your ventilation is combined with heating and cooling or is a standalone function.

“For example, adding DCV to a packaged rooftop unit may be as simple as including the CO2 sensor with a controller that has the DCV control logic built into it. Such a system likely serves only one or a few occupied zones, making it simpler to control CO2 levels,” explains Lawrence. “A larger building with central air handling, however, may serve many occupied zones. Determining the proper amount of outdoor air to bring in at the central air handling unit is also complicated by the variable occupancy patterns within the multiple zones.”

Say your VAV system supplies air to a large conference area and a group of private offices. To scale back the ventilation when the conference room is empty means that you risk the possibility of underventilating the offices at the same time. To avoid this scenario, you will need air flow sensors that measure the amount of air going to each space as well as the outside air that’s being drawn through the air handling unit, says Nall.

CO2 sensors are typically installed in the occupied space instead of ductwork because return air is an average of all conditioned spaces rather than an individual area, state ASHRAE members Mike Schell and Dan Inthout in their article Demand Control Ventilation Using CO2. Duct sensors can be used if all ventilated spaces share common occupancy patterns; otherwise, sensors should be wall-mounted.

“Avoid installing in areas near doors, air intakes or exhausts, or open windows,” advise Schell and Inthout. “Because people breathing on the sensor can affect the reading, find a location where it is unlikely that people will be standing in close proximity (2 feet) to the sensor. One sensor should be placed in each zone where occupancy is expected to vary. Sensors can be designed to operate with VAV-based zones or to control larger areas up to 5,000 square feet.”

Switching to DCV will typically require additional building management system points, new setpoints, and new control codes for dampers, Nohra notes. This may include a controller or DDC programming to communicate either directly with the economizer controller or a central control system, specifies the DOE in its 2012 report on demand control ventilation.
You should also make sure outdoor dampers are operable and not stuck in fixed positions, stresses Lawrence. It’s not unusual to find air intakes blocked in a misguided attempt to save energy. There may also be missing equipment, such as economizer controls with modulating air dampers that were specified but never installed.

Once the DCV sequencing has been established, the system requires minimal maintenance. CO2 sensors should be recalibrated periodically as their accuracy will drift over time. Consult your manufacturer guidelines, which may recommend recalibration every five years, annually, or every six months. Lawrence also recommends sensor testing prior to launch in case the product is deficient or was damaged during installation.

A BREEZY SOLUTION
Demand control ventilation isn’t a flashy energy efficiency project, but it consistently generates payback under five years or less. Paybacks can also be achieved more quickly if the system incorporates lighting and electrical outlets (vampire energy) controls. For upfront investments, owners can expect to pay less than $100 for occupancy sensors, Nall estimates. CO2 sensors can cost several hundred dollars per unit, adds Lawrence.

“The installation costs for a DCV project vary significantly depending on building size, existing infrastructure, and control requirements. An owner can expect to pay approximately $1,000 to $2,000 per point on average,” Nohra adds.
Nall was recently involved with a renovation project that incorporated DCV by using occupancy sensors. A series of perimeter offices and those adjacent to an atrium were paired with a dedicated outside air system and variable speed fan coils.

Each 160-square-foot office has a two-position damper. The default setting for an unoccupied office delivers 10 cfm of outside air. Anticipating occupant diversity when the office is in use, the secondary position is configured for three guests at 25 cfm.

“This ensures that we’re providing the minimum ventilation for the maximum expected occupancy,” Nall stresses.
Whenever the system senses the room is unoccupied, it can scale back ventilation to 40% of peak flow. The project cost less than $1,000 per office and since the occupancy sensor controls ambient lighting and power receptacles, the payback is under five years. The DCV capability also meets the LEED credit for increasing ventilation by 30%.

Lawrence also oversaw a DCV project at the University of Georgia. The retrofit converted a single classroom, but has seen great success since its installation. Payback was achieved in less than two years and there are plans to adapt more areas in the future.

“Regardless of the actual design standard, energy savings with a DCV retrofit should focus on a comparison to the existing ventilation patterns, even if they do not match current codes or standards,” emphasizes Lawrence. “If a building is not providing ventilation that meets existing standards, then the primary benefits of DCV are indoor air quality.”

Jennie Morton [email protected] is senior editor of BUILDINGS.