You don’t need a weatherman to know which way the wind blows.
Shelter from the storm, isn’t that what we are all looking for? March and April in New Mexico is the wind season. Our gusty winds blow last year’s tumbleweeds down the street and also blow a lot of dust and pollen into our homes. Air infiltration through windows is a big issue here in the Southwest. At Glass-Rite our Energy Quest windows are designed to help minimize infiltration through the use of weather-stripping and interlocking parts that create tight seals.
As a homeowner looking for ways to choose windows with low air infiltration here are some things to consider:
First, look at the NFRC label on the windows. There is a performance rating for air leakage (AL). The measured rates for AL typically fall between 0.1 and 0.3, the lower the AL the better a window is at keeping air out. AL is an optional rating so manufacturers are not required to include it but you will find that windows that test well for AL will show the value on the label. The Energy Quest window that Glass-Rite makes here in Albuquerque actually tests so low that the AL value rounds to 0 and this is the certified value we show on our label.
Second, choose window styles that tend to have lower air infiltration. The tightest window styles are fixed window (no surprise there!) followed by casements and awnings. These windows tend to close in on themselves when the wind blows hard and also since they only have one sash they have less exposed perimeter than a sliding window the same dimension. Double hung windows and double sliders tend to have the highest air infiltration because both panels are operable, and there is more opportunity for the wind to get into your house.
When we get very low temperatures in the winter people often feel “drafts” from old windows that have single panes or even from double pane glass that does not have Low E. They assume that the draft is coming from ineffective weather-stripping when they are actually experiencing a draft from convection cooling. This happens when warm air in the home comes up against a cold window pane. The warm air cools quickly and sinks creating a mini draft that will often make it feel like the wind is blowing right through the window, when the real problem is the window is just not thermally efficient enough.
Even the tightest windows have some level of air infiltration though, so to minimize dust and pollen in your home, keep the exterior sills of the window clean and free of dust. Here in New Mexico there is enough dust blowing that it will accumulate on the exterior sill between the screen and the sash and then each time you open the window a little dust will come into your home. If you vacuum or brush this dust away from the outside of the sills, you’ll have a lot less in your home. Also remember that every window has a drainage/weep system and if you let enough dust accumulate on the outside of the window, this drainage system will get clogged and we’ll have water problems when the summer rains come.
To learn more about how to get the most out of your windows give us a call or stop by our showroom and we’ll give you the tour!