Category Archives: LEED

Here’s why you should measure CO2 in your building

The following post is an excerpt from Daphic Scientific by Michael Forster PhD 

iStock_000057422952_LargeCO2 is a known indoor pollutant affecting performance in the workplace, at school, and even at the gym. Extreme levels of CO2 can lead to death, particularly in enclosed spaces such as laboratories, some hospital rooms, and breweries. CO2 can have a number of effects on home and workplace health and safety.

Controlling CO2 can also improve building energy efficiency, saving costs by up to 80%, and is even considered in the scoring of Green Star Ratings in building design.

Here, we outline 7 reasons why you should be measuring carbon dioxide levels inside buildings.

1.  CO2 can kill you

Outside air has a CO2 concentration around 400 ppm and each human breath contains around 30,000ppm.  As CO2 concentration around you increases, symptoms begin by causing panting, followed by tremors and loss of consciousness, and finally death.

CO2 can be hazardous in one of two ways: by displacing oxygen in the blood or as acting as a toxin.

2.  CO2 can decrease productivity

In the office and classroom, elevated levels of CO2, in the range between 1,000 ppm and 2,500 ppm, have been found to decrease concentration, increase headaches, decrease performance, and increase rates of absenteeism.  Generally, CO2 concentrations as low as 1,000ppm can lead to poor decision-making performance.

Although CO2 is not the only factor, elevated levels can lead to that feeling of lethargy and tiredness often associated with office workers.  Studies have shown that lethargy induced by elevated CO2 can decrease performance by up to 10% for adults and over 20% for school children.

3.  CO2 can increase rapidly in poorly ventilated rooms

Figure 1. An example of increasing CO2 concentration in a poorly ventilated office with a single occupant.

Figure 1. An example of increasing CO2 concentration in a poorly ventilated office with a single occupant.

In surveys of school classrooms in California and Texas, average CO2 concentrations were above 1,000 ppm, many exceeded 2,000 ppm, and in 21% of Texas classrooms peak CO2 concentration exceeded 3,000 ppm. Such high levels of CO2 could have a particularly adverse effect on concentration during exam periods.

Generally, where large numbers of people gather then CO2 will increase rapidly and lead to poor indoor air quality and pollution. In offices, this could be meeting rooms where a number of staff gather for extended periods in confined spaces.

Other places, such as gyms, shopping centers, cafes with soft drink vending machines, or libraries, are increasingly being recognized as indoor environments with elevated CO2 leading to poorer performance.

4.  Some locations have naturally high CO2 levels and need to be monitored

Figure 2. The ESRAD-102 CO2 Storage Safety Alarm can save lives in locations where extreme levels of CO2 occur.

Figure 2. The ESRAD-102 CO2 Storage Safety Alarm can save lives in locations where extreme levels of CO2 occur.

There are certain locations where indoor CO2 in an enclosed room or area can potentially reach extreme and life threatening levels.

Laboratories and hospitals may have enclosed or poorly ventilated locations where CO2 cylinders are stored or used and may potentially have harmful levels of atmospheric CO2.

In manufacturing, spaces where CO2 is regularly used are also potential areas of harmful levels of CO2.  Breweries can be extremely hazardous.  Pockets of high CO2 can form in tanks and cellars and can quickly lead to death.  Even bars, clubs and pubs, where CO2 cylinders are stored in a room, are increasingly required to monitor CO2 levels for workplace safety.

Using CO2 sensors for ventilation control can assist in these cases.  However, other systems with audible and visual alarms may warn workers and occupants of dangerous levels of CO2.

5.  Monitoring CO2 for energy efficiency

Facility managers are increasingly turning towards monitoring CO2 for Demand Controlled Ventilation (DVC). Ventilation units can automatically set air intake based on maximum occupancy rate of a room, office or classroom.  However, occupancy is often intermittent and unpredictable and may lead to over-ventilation and energy inefficiencies.  Monitoring CO2 levels and automating ventilation to intake air at pre-defined CO2 levels, such as 800ppm, will increase ventilation when it is actually needed.

One study found that monitoring CO2 for DVC saved between 5 and 80% on energy costs compared with a fixed ventilation strategy.

Other technologies to monitor occupancy level may not be as efficient as monitoring CO2 levels.  For example, humidity set points, which can vary widely, change slowly and not directly reflect occupancy.  Another method is to use a presence detector sensor, or PIR.  This method is used widely to automatically turn on lights when a person enters a room, but this method does not detect how many occupants there are in a room.  Measuring CO2, on the other hand, can determine the presence of an occupant and the number of occupants as the rate of change in CO2 levels will be higher with more occupants.

6.  Improving your green building score

The Green Building Council of Australia scores up to 2 points if CO2 levels are maintained below 800ppm or 700ppm respectively.  This move recognizes the relevance of optimal CO2 level for occupancy comfort and productivity.

The United States Green Building Council scores up to 2 points for indoor air quality assessment.

7.  The novelty factor

Most people would not have a clue what the CO2 levels in their room are, what they should be, and how they change throughout the day with various factors.  Monitoring CO2 levels with a data logger showing real-time CO2 levels is interesting. Informing your guests that you are controlling the ventilation in your building with a CO2 detector will certainly raise a few eyebrows!

CO2 technology, installation, and maintenance

Figure 3. A simplified diagram of the NDIR principle of CO2 measurement.

Figure 3. A simplified diagram of the NDIR principle of CO2 measurement.

There are two types of CO2 sensors.

The first is a simple detector that has either voltage or 4.20mA output that can run back to a BMS. These detectors are ideal where multiple units need to be installed and operated by a single BMS.

The second type is a transmitter. These detectors can connect directly into an HVAC unit to control ventilation. This type is ideal where only one sensor is needed.

Other types can additionally measure temperature and humidity providing a complete monitoring solution.

For more information on CO2 measurement devices, check out the Daphic Scientific Environmental Research & Monitoring Equipment site.

A work or learning place designed for optimal productivity leads to better performance and, ultimately, is better for the bottom line.  Monitoring and controlling CO2 levels is one approach to a healthier workplace environment.

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NFL strikes gold with new 49ers’ stadium

Levis StadiumThe new home of the NFL’s San Francisco 49ers has achieved LEED Gold status, a first for an NFL stadium. Levi’s Stadium in Santa Clara, California, has many green features, including a green roof, solar-paneled pedestrian bridges and a solar-paneled roof deck. But, its most crucial green feature may be the state of the art grey water system.

Up to 85 percent of all water used in the 68,500-seat stadium comes from recycled water. A recycled-water pressure booster system taps into the Santa Clara Valley Water District water recycling system, eliminating the need to use freshwater to flush toilets and irrigate the natural grass field and green roof.  The system is powered by Bell & Gossett brand pumps.

“A recycled-water pressure booster system ensures adequate water is available when everyone goes to the bathroom at one time, like halftime at a football game,” said Mark Handzel, Vice President, Product Regulatory Affairs, and Director, HVAC Commercial Buildings.

The stadium’s water assessment estimates the recycled-water pressure booster system will save over 42 million gallons of water per year. And there are twice as many toilets in Levi’s Stadium as were in Candlestick Park, the 49ers’ former stadium.

The stadium uses highly efficient building systems by Bell & Gossett, including:

  • The centrifugal pumps were selected for the recycled-water pressure booster system.
  • The Rolairtrol air separators, Series 60 inline pumps, 1510 end suction base mounted pumps, and VSX double suction pumps were chosen for the hydronic systems.
  • A brazed plate and GPX gasketed plate, and frame heat exchangers were selected because of their high thermal efficiency for the condenser water system.

The Levi’s Stadium will host Super Bowl 50, next year, on Sunday, February 17, 2016.

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Seattle Lowrise Zones Now Have a Passive House Incentive to Add Floor Area

The following post is by Joe Giampietro, AIA, CPHC, NK Architects

11th and Republican PH Multifamily Rendering

On July 6th, the Seattle City Council passed a number of revisions to the low-rise zone land use code, including adding Passive House as a way to achieve floor area ratio (FAR) bonuses.

A FAR bonus allows for an increase in building height relative to the area of the lot. Passive House efficiency principles lead to significant energy savings, increased project value, and improved health and comfort for those that live there.

Although this was a minor addition to an otherwise hotly debated set of low-rise zoning updates, this addresses building energy use in a practical and cost effective manner. It is a big move in the right direction.

With the addition of Passive House to the other “green” incentive programs, including LEED Silver, Built Green 4-Star, and the Washington Evergreen Sustainable Development Standards for affordable housing, Seattle has started down the road of recognizing and providing incentives for truly high-performance, low energy design strategies.

Next on the list of legislative actions, the Passive House community is working with the Seattle City Council to consider expanding the Passive House incentive to include both current certification agencies, PHIUS and the Passive House Institute. We have successfully lobbied City Councilman, Mike O’Brien’s staff to include this adjustment in the “omnibus” zoning legislation. The expansion language is currently wending its way through the Council approval process and will be voted on later this summer.

We anticipate that this action will serve as a model for other changes in zoning legislation in Seattle as well as in cities and towns in throughout the Northwest. Let’s take a moment to celebrate one small step in this process!

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How to prepare for the LEED exam

The following post is by Jess Foster:

iStock_000063149081_DoubleCongratulations on your decision to pursue a LEED Credential. These are the most sought after credentials in the green building industry by employers. A new study by Burning Glass Technologies shows that demand for LEED Green Associates and LEED APs has grown 46% in the last 12 months, so you’ve picked a great time to join in on this growing marketing need.

Your next step is to prepare for the LEED Exam. Here are some basic things you should know before selecting an exam prep program or materials:

1. Decide which credential exam to pursue:
There are several credentials you can earn based on your profession and your goals in the green building industry. I recommend looking at the USGBC site (the creator of LEED) or resources prepared by their recognized Education Partners like GBRI. Make sure to download the candidate handbook to understand eligibility requirements, registration and scheduling details.

2. Decide whether to study by yourself or sign up for an exam prep course:
Studying on your own can be challenging given the amount of material covered on these exams. Or, you can sign up for a LEED prep course. A quick Google search will show plenty of paid exam prep providers. Make sure the provider you choose is approved by USGBC or are USGBC Education Partners.

3. Choose an exam prep provider and course style:
Depending on your availability and schedule, there are several ways to prepare. There are live online classes where you attend for a month or so; on-demand only access courses where you watch sessions at your own pace; and in-person classes where an instructor teaches at a physical location. Make a selection that is right for you and your situation.Since the new LEED v4 test was released recently, you should carefully make a selection when registering for an exam prep program. An ideal exam prep course will include:

  • Narrated study materials/tutorial with option to download audio files
  • A study guide that you can print
  • Flash cards
  • Section or category quizzes (look for quizzes with answer explanations)
  • Simulated Mock Exams (at least two)

4. Study-study-study:
I recommend studying in a group or with a partner if you can. Finding someone to study with for your exam has many benefits. Some exam prep providers also provide group discounts, making it easier for your colleagues to join you in the pursuit of a credential. If you do chose to study independently with the support of a providers prep program, you’ll want to have a roadmap or plan to ensure you are staying on track and are covering all the material efficiently. Some USGBC Education Partners programs will include a recommended roadmap for you, taking even more of the guesswork out of studying.

5. Take MOCK exams:
Make sure you are completely prepared leading up to your LEED exam by using a trusted provider’s mock exams. This is your best gauge to ensure you will successfully pass the exam on your first try. This also gives you a targeted way to complete your studies and preparations based on the areas you find you are most lacking in during the mock exams. Once you successfully pass the mock exams you can feel confident going into the real thing.

Author Bio:
Jess Foster, GBRI Blog writer, studied history at Furman University, where she encountered the concepts of green living and sustainability for the first time. In her leisure time, she enjoys photographing the wildlife in her backyard and playing with her two Shetland sheepdogs.

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Lush landscaping without all the water

The following post is by Jasmine McDermott:

Z Living Systems installed a water-saving, living wall crafted of 6,000 individual plants on a new resident activity club in Los Angeles. The building, which implements a number of sustainable features, achieving LEED Platinum, ultimately creates an “oasis in the middle of a city.” The 1,200 sq. ft. living wall, featured both indoors and outdoors, stretches the length of an Olympic-sized swimming pool while only requiring less than half the amount of water an individual would use showering in one week.

This living wall in Los Angeles is the length of an Olympic swimming pool.

In response to California’s severe drought, Governor Brown’s office released regulations surrounding water conservation and is encouraging a number of water conservation practices. Z Living Systems incorporates a number of these practices into their living walls creating a sustainable alternative for landscaping.

Z Living Systems’ proprietary system takes plants, hardy drought-tolerant native species, which are first transplanted into the company’s living wall pots from their original nursery pots, delivers them onsite, and then hangs them onto a prefabricated structure. The system allows for first day, full coverage of vegetation. Following the installation, the company utilizes an irrigation controller that allows the control of irrigation remotely in response to weather conditions. In collaboration with Rios Clementi Hale Studios, there was an effort to blur the lines of indoor and outdoor by continuing the living wall through the exterior and interior of the building.

Firms involved

  • Architect- Rios Clementi Hale Studios
  • Contractor- Fassberg
  • Builder- Brookfield Residential

Water Conservation Practices Utilized by Z Living Systems Living Wall

  • Smart irrigation controller
  • Drip irrigation
  • Drought tolerant or native plants
  • Mulch
  • Watering once a week
  • Preventing runoff

Jasmine McDermott is a co-founder of Z Living Systems, a living-wall provider based in San Luis Obispo, California.

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