Green Homes—Window Treatments

Choose recycled and socially responsible materials to control light.

Photo: excitingwindows.com

From awnings, blinds and draperies to overhangs, shades and shutters, consumers have many options for window treatments. Careful selection can bring sound environmental benefits.

Reasons for Window Treatments
Window treatments are more than just decoration. Many are purposeful, says Bernadette Upton of EcoDecor in North Palm Beach, FL. Upton, who is a licensed interior designer, lecturer, and consultant specializing in environmental interior design, says the insulation and privacy factors of traverse draperies are the main reasons so many hotels use draperies for window treatments. In winter, they insulate against extremely cold temperatures, and in summer, they keep the high heat temperatures controlled.

Window treatments also serve to control light coming through windows or skylights. That light can cause: direct or reflected glare on television and computer screens, some fabrics and artwork to fade, and thermal discomfort, says Professor Russ Leslie, associate director of the Lighting Research Center at Rensselaer Polytechnic Institute in Troy, NY, and a practicing architect. “These problems are magnified when direct sunlight enters the room,” he says.

Leslie notes in The Lighting Pattern Book for Homes, a book he co-authored, that daylight sources to keep in mind are the direct sun; the sky, which can diffuse the sun’s light; and surfaces surrounding a building that can reflect sun or skylight into the home.

The U.S. Department of Energy suggests that window treatments offer a variety of benefits:

  • Window awnings. They can reduce solar heat gain in the summer by up to 65 percent on south-facing windows and 77 percent on west-facing windows. Light-colored awnings reflect more sunlight.
  • Window blinds. Whether they’re the vertical or horizontal slat-type, they are more effective at reducing summer heat gain than winter heat loss.
  • Window shades. Properly installed window shades can be one of the simplest and most effective options for saving energy. For greater efficiency, consider dual shades that are white on one side and heat-absorbing dark on the other side. Keep the reflective side always facing the warmer side: outward in cooling season and inward in heating season.
  • Draperies. Their ability to reduce heat loss and gain depends on fabric type and color. For example, the University of Florida found that medium-colored draperies with white-plastic backings reduced heat gains by 33 percent.
  • High-reflectivity window films. They can help block summer heat gain but their effectiveness depends on several factors, including size of window glazing area and window and home orientation.
  • Window overhangs. They can shade south-facing windows from summer heat and allow sunlight and warmth in during winter. Construction and orientation must consider such factors as latitude, climate, and window size and type.

Green Factors
Window treatments can offer many environmentally friendly attributes. They might enhance energy efficiency or be crafted of renewable or recycled materials; be created in manufacturing processes that reduce waste and re-use materials; originate from locally sourced materials to reduce transportation issues; or be created of healthy and safe materials with few or no chemicals and no volatile organic compounds.

Regardless of the green features, avoid “greenwashing” and look for certifications or other proof. (For more information, see the article Greenwashing.)

Victoria Schomer, of Green Built Environments in Asheville, NC, suggests also looking at design and usability. She says that certain window treatments, especially horizontal ones, can be huge dust collectors, a problem for indoor air quality. Look for window treatments that can be easily wiped off, vacuumed clean, or taken down and sent to a green dry cleaner. Be aware that those window treatments that feature stain and wrinkle resistance may mean the material contains chemicals that can affect indoor air quality.

Schomer says window treatments need to be positioned so that they do not cover HVAC vents. Blocked vents will suppress heating and cooling functions. While better-insulated shades, for example, can keep a home cooler on hot days or warmer on cold days, they do necessitate having to open and close them at appropriate times to get the benefits.

Assessing Your Needs
Upton suggests that window treatments may be the one place in home decorating that homeowners, even do-it-yourselfers, need to consult an interior designer or a window professional that specializes in green window treatments.

“There is much more to it than it seems, and there are many factors that need to be considered in addressing all facets of optimizing window treatments for energy, sun control, thermal comfort, privacy, etc.,” she says. Upton says those factors include:

  • Knowing what function you want the window treatment to serve.
  • Addressing the function first, then proceeding with appropriate decoration considering local materials, workrooms and installers.
  • Selecting materials that are sustainable, which can include recycled and recyclable content, and selecting paints and finishes free of volatile organic compounds (VOCs) to optimize indoor air quality.

Always look first to products that are manufactured locally, says Upton. “From an environmental stewardship perspective, it saves energy and it supports the local economy,” she says. “When we’re looking for the actual materials, locally harvested products such as wood should be the incentive, especially if the forest that the wood comes from is practicing certified forestry. Renewable resources are encouraged while rapidly renewable resources are encouraged even more.”

Marketplace Availability
Window treatments that keep green in mind are available from a growing number of companies. 3M, based in St. Paul, MN, for example, offers window film products that block 99 percent of the Sun’s ultraviolet rays, the primary cause of fading and sun damage. They are available through its authorized window film dealers. Its Sun Control Film also reduces glare and improves comfort, reflecting up to 78 percent of the Sun’s heat that comes through the window. For those in hot climates, that reduced heat gain can mean saving on air conditioning costs.

Another 3M product line, the Prestige Series, is a change from traditional films. It is transparent, has low reflectivity. and features superior heat rejection. Its no-metal technology avoids any tendency to corrode in coastal environments or to interfere with wireless devices. Because it is not dark or shiny, it does not change the interior or exterior appearances of your home.

Hartmann & Forbes of Portland, OR, whose handcrafted window coverings are available through interior designers, aggressively cultivates its environmental policies and procedures. Its roman shades and draperies are made from natural materials, including grasses, reeds and bamboo. Its ColourWeave Collection is handpainted using paints designed to exceed LEED environmental standards for VOCs.

Under the company’s environmental program Project Green®, Hartmann & Forbes has worked with eco-experts, including the University of Oregon’s Sustainability Management Department, to help the company minimize its environmental impact across the business.

Though not a manufacturer, Budget Blinds has a vendor network for its more than 1,000 franchise territories across the United States and Canada. It polled its Vendor Alliance and found several good choices for eco-conscious customers. Suzi Carragher, director of corporate communications, notes that the company does verify vendor claims against listings on Web sites of certifying bodies.

The company reports that products from its private label, Signature Series®, are certified by Green Built Home, a Wisconsin-based organization. That program reviews and certifies products that meet one or more requirements such as being Energy Star certified, Certified Organic, or certified by the Forest Stewardship Council.

Carragher says the manufacturer has instituted programs that have resulted in reclaiming 90 million gallons of water annually and recycling 75 percent of its overall waste, which has diverted 43 million pounds of waste from the landfill to recyclers over a decade.