Commercial Remodeling: March 2008 Archives
Researchers in England found that building a new home emitted four and-a-half times as much carbon dioxide as refurbishing an existing dwelling.They also found that the carbon dioxide emitted as a result of the construction of a new building - from quarrying, brick making and so on - accounted for nearly three times more of a building's lifetime emissions than had been supposed.
Previously the amount of energy involved in the construction of a home had been assumed to represent 10 per cent of the energy used over the lifetime of a building.
In fact, energy involved in construction added up to nearly 30 per cent of the emissions over the lifetime of the building, according to the report "New Tricks with Old Bricks; how reusing old buildings can cut carbon emissions." Telegraph, UK
So you can feel better about remodeling an old building than about building a new one. Another benefit of remodeling old structures is reduction in urban sprawl. When new wilderness or agricultural lands are transformed into suburban housing, we lose many additional benfits of nature's natural systems: plants (especially native plants) provide air filtration, water capture and replenishment of aquafers and water tables, wildlife habitat, cooling of the earth, and natural processing of waste -- from animal carbon dioxide to poop :-) Nature works hard for us and we can return the favor by reusing what we have already taken out of the natural system instead of adding to the concrete jungle.
- Homes that are ineffectively insulated and are not sealed against air infiltration in cold climates can result in major moisture problems.
- Cool interior surfaces such as pipes, windows, tile floors, and metal appliances; air conditioner coils with poor outside drainage; masonry or concrete surfaces; toilet tanks; and, in the winter, outside walls and ceilings can result in moisture buildup from condensation. If the temperature of an interior surface is low enough to reach the dew point, moisture in the air will condense on it and enhance the growth of mold.
- Dehumidifiers used in regions where outside humidity levels are normally 80% or higher have a moisture-collecting tank that should be cleaned and disinfected regularly to prevent the growth of mold and bacteria. It is best if dehumidifiers have a drain line continuously discharging directly to the outside or into a properly plumbed trap. This is also true in climates where air conditioning units are used on a full-time or seasonal basis. Their cooling pans provide an excellent environment for the growth of allergenic or pathogenic organisms.
- Moisture removed from clothing by clothes driers ends up in the dryer vent if it is clogged by lint or improperly configured. Moisture buildup in this vent can result in mold growth and, if leakage occurs, damage to the structure of the home. The vent over the cooking area of the kitchen also should be checked routinely for moisture or grease buildup.
The control of moisture in a home is of paramount importance. It is no surprise that moisture control begins with the design and integrity of the roof. As in nearly all construction materials, tradeoffs must be made in terms of cost, thermal efficiency, and longevity. However, all roofs have two things in common: the need to shed moisture and protect the interior from the environment.
Insulation
A house must be able to breathe; therefore, air must not be trapped inside, but must be allowed to exit the home with its moisture. Moisture buildup in the home will lead to both mold and bacteria growth.
Siding
Good siding should be attractive, durable, insect- and vermin-resistant, waterproof, and capable of holding a weather-resistant coating. Fire-resistant siding and roofing are important in many areas where wildfires are common and are required by many local building codes. Wall surfacing can include choices as diverse as fiber cement, bricks, stucco, vinyl, asbestos (beware of contamination), and metal.
RESOURCE: Center for Disease Control provides an online book with many building guidelines to prevent health problems.
Quality of the air and environment inside buildings is based on pollutant concentrations and conditions that can affect the health, comfort and performance of occupants -- including temperature, relative humidity, light, sound and other factors. Good IEQ is an essential component of any building, especially a green building.
Creating a better indoor environment can help building owners, managers, occupants, architects and builders to minimize or eliminate the negative health effects, liability, bad publicity, and costly renovations and repairs often associated with IEQ problems.
Improving IEQ involves designing, constructing, commissioning, operating, and maintaining buildings in ways that reduce pollution sources and remove indoor pollutants while ensuring that fresh air is continually supplied and properly circulated.
EPA’s Indoor Environments program promotes the use of integrated, whole building approaches to protect occupant health while saving energy and money. The program focuses on major building types including offices and institutional buildings, schools, homes, as well as major cross-cutting indoor air quality issues like mold and moisture. EPA offers resources from informational pamphlets to interactive CD-ROMs on how everyone from builders to homeowners can improve their indoor environment.
Call EPA's Indoor Air Quality (IAQ) Information Clearinghouse at 1-800-438-4318. Or visit EPA's list of free publications at epa.gov/iaq/pubs
Some air cleaners use ultraviolet (UV) light technology intended to
destroy pollutants in indoor air. These air cleaners are called
ultraviolet germicidal irradiation (UVGI) cleaners and photocatalytic
oxidation (PCO) cleaners. Ozone generators that are sold as air
cleaners intentionally produce ozone gas, a lung irritant, to destroy
pollutants.
- UVGI cleaners use ultraviolet
radiation from UV lamps that may destroy biological pollutants such as
viruses, bacteria, allergens, and molds that are airborne or growing on
HVAC surfaces (e.g., found on cooling coils, drain pans, or ductwork).
If used, they should be applied with, but not as a replacement for,
filtration systems.
- PCO cleaners use a UV lamp along
with a substance, called a catalyst, that reacts with the light. They
are intended to destroy gaseous pollutants by converting them into
harmless products, but are not designed to remove particulate
pollutants.
- Ozone generators use UV light
or an electrical discharge to intentionally produce ozone. Ozone is a
lung irritant that can cause adverse health effects. At concentrations
that do not exceed public health standards, ozone has little effect in
removing most indoor air contaminants. Thus, ozone generators are not
always safe and effective in controlling indoor air pollutants.
Consumers should instead use methods proven to be both safe and effective to reduce pollutant concentrations, which include eliminating or controlling pollutant sources and increasing outdoor air ventilation.
Visit www.epa.gov/iaq/pubs/ozonegen.html for more information on ozone generators sold as air cleaners.
