Breathe Easy: Fighting Air Pollution Inside Your Home

Part I: Overview — Introduction to Green Building

Part II: Land Use Planning — Creating Value, Protecting the Environment

Part III: Material Science — New Options in Eco-friendly (and Healthier!) Building Materials

Part IV: Be a Miser — Strategies for Slashing Your Energy Consumption

Part V: A Drop in the Bucket — Painless Ways to Reduce Your Water Use

Part VI: Breathe Easy — Controlling Pollution Inside Your Home

Part VII: Xeriscaping — Drought-resistant, Low-maintenance Landscaping

Part VIII: Greening America — Green Certification and a Look at the Costs

We all know about air pollution — from factory and power plant emissions and automobile exhaust. But did you know that the air you breathe inside is typically three to five times dirtier than the air outside?

The Environmental Protection Agency has stated that indoor air pollution is one of the nation’s top environmental health concerns. Asbestos, lead, tobacco smoke, volatile organic compounds (VOCs), dust mites, pollen, bacteria,  mold spores, carbon monoxide and pesticides are just a few of the contaminants commonly found in the indoor air of the typical American household.  And the home is where most of us spend 65% of our time. Poor indoor air quality isn’t just hazardous to our health (more than 40 million people suffer from asthma and allergies in this country), it’s bad for your home too, causing structural and finish degradation. But there is much

Go to the Source

Preventing pollutants from ever entering the airstream in your home is the first step to optimal indoor air quality. “The foundation of a healthy home is literally in the crawl space,” says David Slater, president of Stream Residential, a local company that partners with homeowners and builders to design solutions for healthy, energy efficient homes. “If your crawl space is sick, so is your house.” Mold, says Slater, is so often the culprit when it comes to respiratory problems, and dark damp crawl spaces are incubators for all manner of mold growth.

The old thinking was that ventilating crawl spaces helped to keep them dry, but now experts advise the opposite. “Those vents just let moisture in,” says Michele Myers, president of M Squared Builders & Designers. “Sealing the crawl space and controlling humidity there is extraordinarily powerful as far as indoor air quality is concerned.”

Myers has a passion for building homes as free as possible of air pollution. Her personal struggle with severe allergies has been a catalyst for intensive research into what makes a healthy house.

“You know, one of the most important things you can do to improve your indoor air quality is to simply clean your house,” says Myers. “And I highly recommend a central vacuum system.” Central vacuum systems, says Myers have more powerful motors than portable vacuums, and they don’t just capture contaminants with a filter, they remove them completely to a remote containment location.

In addition to sealing the crawlspace, Myers advises homeowners to ensure that the entire building envelope is tightly sealed and moisture levels controlled, from the attic to the basement. She also cautions homeowners to pay attention to the materials they select when building, renovating, even furnishing their homes.
 
Volatile organic compounds (VOCs), a family of chemicals that vaporize at room temperature, are present in many widely used household products: pesticides, cleansing solvents, cosmetics, deodorizers, paint and tobacco smoke. And VOCs are also found in a variety of building materials, as well as furnishings:
cabinetry components (particularly composite woods), architectural trim, paint, carpeting, furniture, mattresses, and even silk plants.

Many manufacturers today are responding to demands for low- or no-VOC emitting products in the home. The GREENGUARD Environmental Institute (www.greenguard.org) offers an independent certification program for products with low chemical and particle emissions. “Florida Tile is the first tile manufacturer to have its products certified for low chemical emissions by the GREENGUARD Environmental Institute,” says Mark Wilson, sales representative for Florida Tile. “We have seen so much interest in issues of air quality and the environment, and we’re pleased to be able to respond with products to meet those demands.”

Renovation and construction can introduce pollutants into indoor air as well. Hardwood floor sanding has long been a major contributor to dust contamination. Selecting contractors who capture and remove contaminants at the source should be a part of your overall strategy to reduce the introduction of pollutants into the indoor air environment. Lee’s Hardwood Floors now offers virtually dust-free floor sanding with powerful vacuums, fitted with highly efficient filters. “Wood dust is carried directly to the dust containment system, which is mounted to a trailer outside the home,” says Tina Lee of Hardwood Floors’. “It’s extremely effective, and we’ve been getting rave reviews from our customers.”

Dirty, leaky ducts are yet another source for the introduction of airborne contaminants. Stream Residential advises careful sealing of ducts and cleaning using only EPA recommended cleaning methods. “And if you are remodeling, wait until your project is finished before cleaning your ducts,” says David Slater.

A Breath of Fresh Air

It’s not possible to eliminate the introduction of all sources of air pollutants in the home. So the next best defense is fresh air. “In today’s tightly sealed homes, it’s more important than ever to ensure ventilation and the introduction of fresh air,” says Michele Myers.

Energy recovery ventilation (ERV) systems are mechanical ventilation systems that provide a controlled way of ventilating a home while minimizing energy loss. They reduce the costs of heating ventilated air in the winter by transferring heat from the warm inside air being exhausted to the fresh (but cold) supply air. In the summer, the inside air cools the warmer supply air to reduce ventilation cooling costs. These systems can also help to regulate humidity levels inside the home.
 
Properly sizing and maintaining air conditioning and heating systems is vital to healthy air circulation and humidity control. “Underperforming HVAC equipment is a national epidemic,” says Stream Residential’s Slater. “An HVAC system that is not operating optimally has an enormous effect on air quality.” Slater cautions homeowners to rely on trained professionals to design systems that are not oversized and to maintain those systems. He recommends at a minimum, that homeowners have a trained HVAC technician perform semi-annual maintenance.
 
Clean it up

The third step in your healthy indoor air strategy is filtration. Once you’ve reduced the sources of airborne contaminants as much as possible, and ensured adequate introduction of fresh air, to avoid accumulation of pollutants, filter the air inside your home to capture or kill much of the remaining contributors to poor indoor air quality. But good filtration is about so much more than the filter you change on your HVAC unit (which really does more to protect the equipment than to actually clean the air in your home).

Indoor air pollutants fall into two major categories: particulate includes dust, smoke, pollen, dust mites, mold, bacteria and viruses; gaseous pollutants include VOCs and carbon monoxide. Different pollutants require different types of filters. Two types of air filtration devices can remove particles from the air — mechanical air filters and electronic air cleaners.

Mechanical air filters remove particles by capturing them on filter material. These filters are rated using the industry standard called MERV, which measures the filter’s ability to trap particles. The higher the MERV rating, the more efficient the filter is at trapping particles. The American Lung Association recommends filters with a MERV rating of 12 or higher for homes with asthma or allergy sufferers. But beware using high MERV-rated filters on your HVAC return, as this can restrict airflow, diminishing the system’s performance. But a whole house filter, using this type filter media can be very effective at removing allergy and asthma aggravating particles from your indoor air.

Electronic air cleaners, such as electrostatic precipitators use a process called electrostatic attraction to trap charged particles. They draw air through an ionization section where particles obtain an electrical charge. The charged particles then accumulate on a series of flat plates called a collector that is oppositely charged. Ion generators, or ionizers, disperse charged ions into the air, similar to the electronic air cleaners but without a collector. These ions attach to airborne particles, giving them a charge so that they attach to nearby surfaces such as walls or furniture, or attach to one another and settle faster.

Another technology, UVC radiation, uses a particular wavelength of ultraviolet radiation, not to remove particulate, but to destroy biological contaminants, such as bacteria, viruses, mold spores and dust mites. “We offer a device that is quickly and easily installed on your existing HVAC system,” says Daniel Goetz, president of Ultraviolet Devices. “For asthma sufferers and immuno-compromised individuals, this can have a meaningful impact on their quality of life.”

Gas-phase air filters remove gases and odors by using a material called a sorbent, such as activated carbon, which adsorbs the pollutants. These filters are typically intended to remove one or more gaseous pollutants from the airstream that passes through them.

With so many options when it comes to air filtration, Stream Residential’s David Slater recommends consulting with a professional to design a filtration system tailored to your specific needs.

“Our approach to healthy indoor air quality,” says Slater, “is to view the whole house as an interconnected system and to design solutions that ensure that the entire system is working to create a truly healthy, efficient and comfortable home.”

Kelly McCall Branson is a freelance writer

Insulation Photo Courtesy of Stream Residential

Bathroom Photo Courtesy of Florida Tile

Central Vacuum Photo Courtesy of Beam Central Vacuum Systems

Filter Photo Courtesy of HealthyHomeFilters.com