On windy days, do you hear your windows rattling? How about the curtains? Do they sway when a breeze kicks up? Drafty windows can do more than make your home grumble and sigh. They can force your HVAC unit to work harder to keep indoor temperatures comfortable, which in turn can lead to higher utility bills. In fact, the Department of Energy (DOE) recently estimated that drafty windows can cost up to $330 a year in additional heating or cooling costs. That’s enough to send a chill up any homeowner’s spine. But what causes windows to become drafty? And what can be done about it? Here are three common causes of drafty windows.
Upon installation, windows are caulked along all seams and edges, and the spaces between the jambs and framing members are filled with insulation. Unfortunately, caulking doesn’t last forever and insulation degrades over time. When this happens (and it will happen eventually) it creates gaps that allow air to pass through. How long your seals last will depend on several factors, including how often you open and close the window (wear and tear), and what kind of climate you live in. Temperature extremes cause windows to contract and expand, which stresses the seals.
If your new windows are drafty, it’s almost certainly the result of improper installation. As explained above, windows must be properly caulked and insulated if they are to prevent air leakage. The window jamb must also be perfectly aligned within the frame to ensure an airtight fit once the caulking and insulation have been added. This is a precise, multi-step process, and it’s not unheard of for even professional installers to improperly position the frame ever-so-slightly.
Even the simplest window is still a complex piece of machinery, with plenty of parts that must work in conjunction with each other to provide optimal weather protection. It doesn’t take a complete component failure to cause a window to become drafty. Worn-out gaskets, subtle frame warpage, and thinning glazing can allow air infiltration even if the window is still fully functional.
How to Tell if Your Windows Are Leaking Air
We’ve already mentioned a few of the more obvious indications that your windows are allowing air to infiltrate your home. But more often than not, drafts are subtle, elusive, and hard to detect. A professional energy auditor can conduct a pressurization test using extremely sensitive equipment to find even the smallest leak. There are also a few things you can do on your own that will give you a better idea of the state of your windows. The following techniques work best on windy days:
- Close all windows and doors
- If you have a fireplace flue, shut it
- Turn off any fans in the house
- Light an incense stick and hold it close to the edges of the window or
- Wet your palm and do the same
If your windows are leaking air, the smoke rising from the incense stick will waver. You should also be able to feel a cool sensation across your damp palm.
What to Do if Your Windows Are Drafty
For a quick and temporary fix, there are several steps you can take to improve your windows’ ability to keep out drafts. V-seal weather stripping can be added along the sashes. Shrink-and-seal films can be added over the window’s inner frame. Even a few daps of carefully applied nail polish can be applied to cracks.
Most of these techniques eliminate the ability to open and close the window, so they are not intended to be a final fix. The surest way to eliminate drafts is to have the old windows replaced with new, energy-efficient ones. At The Window Depot, we are the Tampa Bay area’s premium exterior contractor and offer a variety of impact and non-impact windows from such leading manufacturers as PGT, Simonton, and CWS. If you’re ready to upgrade your home, reach out to us today and schedule a no-obligation consultation. You can also visit our expansive showroom in Palm Harbor to see full-scale mockups of our windows first-hand.