Courtesy of Curtis Lumber
By Susan Elise Campbell
As window manufacturers make strides in energy efficiency, consumers may find that even though it costs more to purchase the higher Energy Star® standard, the benefits of the investment are worth it. These may include the comfort they feel in their home or business, long-term savings on heating and air-conditioning, and protection of the environment, according to www.energystar.gov.
Ian Young is director of commercial sales for Curtis Lumber Company. While he works out of the Ballston Spa location at 885 Route 67, he oversees the commercial sales process for the company’s 21 stores in New York and the two in Vermont. Along with the company’s on-staff architectural engineer, he advises commercial builders on the best choices for windows, doors and skylights for their projects.
Young explained what makes newer windows increasingly energy efficient.
“It comes down to the glass as well as some modifications to the window frame,” said Young.
Vinyl windows have thermal breaks, a series of chambers in the frame that allow for better efficiency by breaking up the transfer of cold or heat between the interior of the building and its exterior, he said.
“There may have been three thermal breaks previously, whereas some manufacturers now design the window to have five or eight areas in the vinyl frame, depending on the company,” he explained. “The more areas, the more energy efficient the product is.”
As enhancements are made, these soon become standard on a manufacturer’s products and factor into their prices, Young said. Foam fill is an add-on feature to cut down temperature transfer and adds 8 percent to 10 percent to the cost of a standard replacement or new construction window.
Today’s standard energy efficient window has two coatings and is going up to three, according to Young, adding that “there is also an option to purchase triple-pane products, where there is an additional layer of glass filled with argon gas.”
Standards change, however. The authorities want to see improvements in the product’s U-value and solar heat gain, which are what qualifies the product for an Energy Star rating and which are the two components Curtis Lumber looks at when advising customers in the market for windows, doors and skylights, Young said.
U-value indicates how well the window prevents heat from escaping. Solar heat gain measures how much warmth can be gained from the sun. Both are important in New York and the Northeast, where the four seasons appear to be getting more extreme.
Whereas a highly rated window may have had a U-value of .27 in the past, a value of .25 or lower meets the requirements for commercial projects today, said Young. The higher the U-value, the more solar heat gain would be required to hold the heat in winter months.
Low-E glass and coatings became part of the Energy Star rating system early on because these minimize the infiltration of ultraviolet and infrared rays passing through the glass, he said. Some manufacturers are also making an “energy panel” option, which is “essentially a storm window that fits on the inside frame of the unit instead of the outside,” Young noted.
“The interior storm window is not sealed, so it can be taken on and off,” he said. “But it provides another layer of air space.”
While today’s windows are better made, condensation can still happen. Young said new types of coatings on the interior pane that cut down hot or cool air from escaping are performing so well that condensation can occur when there are big swings in temperature, meaning that the natural transfer of moisture cannot occur. This will continue to happen as buildings get tighter and tighter, he said.
Windows made for residential or commercial use are not different in themselves, but the application and the installation may be, according to Young.
“A commercial building’s use is the key determinant in those factors,” he said.
For example, there are design and safety criteria for senior housing or assisted living facilities that state authorities and the federal Americans with Disabilities Act require.
The direction the building faces can also factor into the choice of windows. A homeowner on Lake George wants to face the water but the light or wind exposure may not be ideal for efficiency, he said.
On the commercial side, Young said his firm initially qualifies the budget, construction time line, and the occupants of the facility. Comfort may be more of a factor for apartment units and hospitals than office spaces, for instance. Then the windows are built out accordingly.
Curtis Lumber’s commercial division employs one architectural representative whose sole function is to be a resource for the architectural community. This individual acts as a liaison between the company and a client’s architect. They also work with the outside sales representative to provide samples and assist in matching product options with the energy requirements and aesthetic specifications of the contractor, said Young.
“Curtis Lumber has become expert at understanding what the requirements are for residential and commercial projects, and does continuous training to stay up to date on codes so we can put forth the best solutions for customers,” he said.
Learn more at www.curtislumber.com and www.energystar.gov.