Notes from a Remodeling & General Contractor for the Wichita, KS Area
When looking for new replacement windows for your home in Kansas, you can run into a lot of technical terms and jargon that isn’t always explained. To makes worse, different manufactures, rating agencies, and dealers often use different terms to often describe the same thing. That can make it difficult to compare windows and manufactures.
We’ve compiled a list of common terminologies that our customers typically have questions about when talking to us regarding replacement windows at S&A Construction in Wichita, KS.
We’ve further focused our explanations more on the real-world value to the home owner vs. a scientific or technical explanation.
Replacement Windows Terminology & Real-World Explanations
What is Low E coating?
Low E coatings are applied to the glass and work by reflecting or absorbing infra-red light (heat). Typically Low-E coatings utilize a metallic coating on the glass. Some Low-E coatings also help protect against the sun’s ultraviolet (UV) rays which cause fading of interior furnishings.
What is Argon gas?
Argon is used for thermal insulation in energy efficient windows because it is inert and has low thermal conductivity. The less heat that is transferred, more cooler your home stays in the summer and the warmer it stays in the winter.
What is Krypton gas?
Like Argon, Krypton is used for thermal insulation in energy efficient windows because it is inert and has low thermal conductivity. The less heat that is transferred, more cooler your home stays in the summer and the warmer it stays in the winter. But krypton is more efficient in smaller gaps between the glass panes thus why it is used typically in triple pained windows. It is also more expensive than argon.
What is U-factor?
The U-factor (sometimes labeled U-value) is measurement of how well window materials conduct heat. A smaller U-factor is better at reducing heat transfer and thus more efficient against heat loss.
What is R-value?
Like the U-factor, R-value is another measurement of the resistance to heat flow through a window. A higher R-value is better at reducing heat transfer and thus more efficient against heat loss.
What is G-value?
Unlike the U-factor and R-value, the G-value (also sometimes called Solar Factor) only measures the solar heat transmitted through the glass of a window. Having a high or low G-value is beneficial depending on if it is winter (heats things up when it is cold) or summer (heats things up when it hot). Typically it is best to have a low U-factor combined with a G-value that is not too high.
What is SHGC?
Solar Heat Gain Coefficient refers to how well the window as a whole (not just the glass) transmits solar energy. Occasionally you may see the term center-of-glass SHGC used but that is the same as the G-value.
What is Shim Space?
The shim space is the area between the window frame and the opening in the house. You can improve energy efficient if the shim space is sealed and filled with fiberglass or low-expanding foam insulation during installation.
What is Tempered Glass?
Tempered glass (also called safety glass) has been heat-treated to increase its strength. When tempered glass breaks, it does so into pebble-sized pieces vs. sharp shards and slivers.
What is Design Pressure (DP) rating?
Design Pressure (DP or sometimes DRP) rating represents the maximum pressure that a window or door can experience without breaking, deglazing or permanently distorting. For example, a window with a DP30 rating is the equivalent to a 110mph wind speed pressures and a DP40 rating is the equivalent to a 127mph wind speed pressures.
Both water penetration and structural testing are based on a window’s DP rating. Water infiltration is tested at 15% and structural is tested at 150% of the DP rating. That typically means that the higher the DP rating the higher the water resistance and structural durability of the window as well.
ENERGY STAR is an EPA standard to help consumer’s select high-efficiency products which are more environmentally friendly. ENERGY STAR labels on windows indicate the products use less energy, allowing you to save money and for the windows to pay for themselves over time.
NFRC Certified Ratings or Label
The National Fenestration Rating Council is an independent rating and labeling organization for the energy performance of windows and doors. Their labels are similar to the EPA’s Fuel Economy & Environment Label on a new car, just for windows and doors. It provides many of the above values or ratings in one place so you can easily compare windows.
Picking the right windows for your home is difficult enough without all the confusing terminology. We recommend working with a local Kansas based company that is A+ Rating with the Better Business Bureau. A reputable replacement windows installer like S&A Construction can help the home owner cut through the jargon and determine which replacement windows will work best with the home as well as offer free estimates.