Technical Updates

Archive for the ‘Technical Updates’ Category

Calculating ventilation rates just became a little easier with a new iPhone application designed specifically for ASHRAE Standard 62.1-2007, Ventilation for Acceptable Indoor Air Quality.

The Standard has been used for years as the measuring stick for indoor air quality ventilation for the building industry. Typically, a “62MZCalc.xls” Excel spreadsheet accompanies the Standard and is used for calculations. With the new app, engineers can make comprehensive minimum ventilation calculations using either I-P or SI units right in the field using their mobile device, without having to return to the office.  

In addition, they can create and store multi-system projects, instantly see updated results as input values are changed, and email results and spreadsheet back to the office for further analysis.

“The ASHRAE 62.1 app can also be used to determine 62.1 compliance of simple ventilation systems (single zone, 100 percent outdoor-air and changeover-bypass VAV) as well as more complex ventilation systems (single-path, multiplezone recirculating) and can operate in both IP and metric units.”

ASHRAE is pleased to be able to utilize the latest smart phone technology. The application works with the iPhone, iPod touch, and iPad and can be purchased for $19.99 through Apple’s online iPhone App Store.

Click here for more details.

We just read a very telling line in a recent article about selling green products or services in a difficult economy.

The author quotes the CEO of an entrepreneurial company as saying that “for customers in today’s economy, it’s either the bottom line or environmental stewardship…and they don’t necessarily go hand in hand.”

It’s always interesting to see how the “green factor” is tempered with long-term sustainability concerns and with people’s purse strings.

As the article’s author explains,”Green startups are finding it difficult to turn profits these days. Those selling green products or services face the extra hurdles of introducing something new that people have to get used to and typically costs more upfront.”

He goes on to say that during the current economic downturn, ”entrepreneurs are changing their business models, switching target customers, or in some cases, putting the company on hold.”

In some cases, this has meant switching over from selling to leasing products. In other scenarios, it has meant alternating marketing strategies: instead of promoting the product or service directly, the entrepreneurs have begun educating the public on the product’s return on investment within a few years’ time.

Still, the road for green companies is tough, as they must fight against bottom line considerations that often take precedence over environmental stewardship.

For the full article, click here.

In an economic climate where everyone is looking to save money and minimize expenses, sustainable buildings have taken off in popularity and demand. The proliferation of green building design reflects a rapidly developing fan base.

According to a U.S. Green Building Council official, “The green building market has basically tripled for the last two years, which is a good sign that it’s flourishing. Developers and owners are seeing the value in green building as a competitive differentiator. The bottom-line decisions are becoming paramount in terms of lowering operating costs.”

According to USGBC findings, green buildings, on average, use 40 percent less water; spend 30 percent less energy; and reduce carbon emissions and solid waste by 35 percent and 70 percent, respectively. These bottom-line savings are causing building owners to be willing to spend more money upfront in order to recognize significant savings down the road.

In many cases, building owners who have been racked by recession woes are turning to green retrofits of existing structures in an effort to remain competitive. Part of the issue is that tenants are considering building performance as one of their top factors when choosing where to rent. Energy-efficient buildings tend to maintain higher occupancy levels and bring in higher rents as a result.

Click here to read the full report and to learn about developments, individuals, campaigns, councils, companies, and services who have chosen the sustainability path.

Obama’s new green requirements for federal buildings will likely catch on up in Canada in the near future, says a Canadian journalist in a recent article called “U.S. green wave is moving north”.

Ottawa-based Korky Koroluk advises fellow Canadians that those within their construction industry should be aware of an executive order signed by U.S. President Barack Obama last October “setting out numerous green requirements for the U.S. federal government and requiring various government agencies to meet a number of energy, water, and waste-reduction goals.”

Although for now, these requirements only apply to federal buildings, he argues that “government construction is a trend-setter” and that it is only a matter of time (once private sectors begin demanding what they see being successfully implemented at the federal sector) before the rest of the construction industry is impacted.

Some of the new ”green” requirements include:

• the need for a 26% improvement in water efficiency by 2020;
• a new emphasis placed on sustainability requirements;
• a net-zero-energy requirement for all federal building projects by 2030.

Koroluk asserts that “by encouraging the promotion of green public-private partnerships, the government is using a powerful lever on the way to sustainable buildings”… and says that “given the Canadian tendency to look southward for innovation, it seems likely that many of the things that are just beginning to happen in the U.S. will slowly find their way into Canadian practice.”

Click here to read the article in its entirety.

How a company makes the leap into “green” can either lead to great success and an increased presence in this environmentally conscious marketplace, or to additional problems and more liability.

We’d like to recommend an excellent article called How to Avoid Litigation Risks from Greening Your Products by Nexus, a project of the The Green Roundtable. (Article was originally printed in GreenBiz on May 5, 2010.)

The authors argue that “it is essential to understand what it means to green your product and consider the risks of going green up front in order to avoid ending up in the courtroom down the road.”  They explain the criteria by which one can determine that a product is green, and describe the legislative landscape for green product manufacturers.

Colorful green litigation could result from not probing and asking important questions ahead of time – questions like: Does marketing a product as green create a warranty? Can a manufacturer be liable for failure to warn or for providing a product claimed to provide certain benefits that does not live up to these representations? What if a manufacturer is selling its product for use in a green building and represents it will obtain a certain certification, but is unable to do so? These types of questions typically end up getting resolved in the courtroom.

Click here to read the article in its entirety.

As a follow-up to our coverage last year on the Chinese drywall issue, here’s the latest update on the issue:

“As many as 152 families from three Homestead neighborhoods will be a part of the first class-action suit in the country over tainted drywall imported from China, providing hope that American companies will also have to pay for damage from the product, installed in new homes built during the housing boom and after a parade of hurricanes in 2004 and 2005.

Homeowners will receive a notice in the mail asking if they would like to join the suit.

Some brands of drywall imported from China have been found to emit large amounts of hydrogen sulfide, which corrodes and blackens some metal in homes and can make houses smell like rotten eggs. Many homeowners also believe the drywall is responsible for breathing problems and nosebleeds.”

Click here for the full story.

Here’s an interesting  green building-related story to follow: NYC condo unit owners file suit against LEED Gold-Hopeful  Riverhouse in Battery Park City.

This potentially high-profile NYC green building lawsuit (including celebrity purchasers Leonardo DiCaprio and Tyra Banks) is a result of a building being “marketed as being at the cutting edge of ‘green’ technology. It is supposedly a LEED Gold-rated building featuring fresh filtered air, filtered water, eco-friendly materials and is designed for low energy consumption. However, plaintiffs have consistently experienced cold drafts and insufficient heat in their Unit.”

Other allegations go on to describe “pipes that are not insulated, heating unit covers that are not sealed, and air filters that are clogged. The purchasers then allege that these failures constitute a breach of contract under the offering plan, and that the developer’s representations in the offering plan about the building and its units were false and therefore fraudulent.”

Click here to read the full story.

HVAC systems can contribute to IAQ problems in at least three ways:

• Inadequate building pressurization and dehumidification
• Intrusion of high-moisture outside air
• Inside surfaces of equipment that promotes or permits microbial growth

The HVAC system complements the building envelope by properly conditioning the building’s interior, including the building envelope, and pressurizing the building with dehumidified air (called exfiltration). When negative building pressurization occurs in humid climates, multimillion-dollar moisture and mold problems can result from intrusion and condensation of moist outside air.

HVAC systems that positively pressurize a building space by supplying unconditioned or only partially conditioned outside air will avoid infiltration of outside air through the building envelope. However, this same situation can result in moisture loads inside the building that exceed the dehumidification capabilities of the HVAC system. One of the most significant causes of moisture accumulation in existing buildings in hot, humid climates is an overemphasis on ventilation at the expense of proper dehumidification.

AC equipment is typically more efficient in cooling air than in dehumidifying it. As a result, unconditioned outside air brought into a building is often cooled to the desired temperate before it is properly dehumidified, creating elevated RH levels and microbial growth inside the building. Furthermore, because AC equipment is typically controlled by temperature (thermostat) instead of by humidity (humidistat), the equipment never senses the elevated moisture level within the building space and therefore never fully removes it.

In any climate, the normal functioning of standard AC units can result in microbial growth. Just downstream of the cooling coils, the air is at or near 100 percent RH during the cooling season. The interior surfaces of the AC unit and ductwork immediately downstream of the cooling coils are often lined with insulation, generally for acoustical purposes. Dirt and fungal spores are often trapped in the lining. This environment is conducive to microbial growth and can lead to IAQ complaints because the conditioned air (and any microorganisms it carries) is distributed inside the building.

To be continued…

In hot, humid climates, one membrane can often act as the secondary weather barrier, air barrier, and vapor retarder. The most common of these membranes is “peel-and-stick” bituthene membrane (self-adhering composite membranes of rubberized asphalt bonded to polyethylene film) installed in masonry wall cavities or directly behind envelope finish materials, such as fiber-cement siding or stucco on lath.

In temperate climates, such condensation can easily occur in the winter, wetting the wall components. Even with low indoor RH levels, the wide temperature differential through the wall generally ensures that a first plane of condensation will be within the wall. Not only does condensation in such conditions cause mold growth, but the wetting of insulation reduces the wall’s thermal effectiveness.

Thus, the building envelope plays a vital role in minimizing uncontrolled moisture and air movement into a building and in preventing moisture entrapment within the wall. Although the building envelope contributes to moisture-related IAQ problems in hot, humid climates, infiltration of humid outside air and vapor diffusion through the envelope is not usually as great a factor in more temperate climates.

However, in temperate climates, the building envelope plays an important role in minimizing rainwater intrusion into the building, and in avoiding the subsequent mold growth that can result from such intrusion. In very cold climates, vapor diffusion or exfiltration of humid indoor air during colder months can also be a problem in wall cavities.

(To be continued…)

With the widespread use of mold-prone, porous sheathing materials (such as exterior gypsum sheathing), the selection of the waterproofing membrane in the drainage plane and its interface with the flashing requires more careful thought. Breaches in the waterproofing layer can easily result in wetting, degradation, and mold growth on the sheathing and other wall materials, including the interior drywall.

Failures of exterior insulation and finish systems (EIFS) installed in the 1980s and 1990s have been widely reported. The early uses of this European system in the United States often failed because they relied entirely on the primary weather barrier of the synthetic stucco. When this stucco failed, often where it joined other building components such as windows, water penetrating behind the insulation could not drain out. The porous sheathing materials (most likely gypsum or oriented strand board [OSB]) absorbed the water, degraded, and failed. Newer EIFS designs require drainage planes in the wall system, which reduce the likelihood of such water drainage problems.

To control air and moisture flow through the wall, any air barrier or vapor retarder must have the proper air resistance or moisture permeability and must be installed at the correct location within the walls. The presence of multiple vapor retarders within a wall system is a common problem, and many architects do not recognize that common construction materials act as effective barriers. For example, exterior grade plywood is a relatively low-permeability material that can function as a vapor retarder.

Condensation tends to occur where cool surfaces meet warm, moist air. If moisture-laden outside air is retarded before it meets the first cool surface inside the building envelope (often called the “first plane of condensation”), then few problems will result. If this moisture is allowed to further enter a wall system, it will condense. That is when moisture and microbial growth problems threaten. If the cool surfaces and moist air meet within the occupied space, then moisture problems can occur throughout the building, resulting in widespread mold odors and complaints from occupants.

To be continued…