By Vlad Kuleshov, Founder & Lead Technician at CapaHome LLC • Updated September 2026
Every single year, right around the second or third week of October when that first bitter 25-degree gust blows off Lake Michigan, our phones start ringing nonstop. The complaints are almost identical: *“Vlad, my furnace is running twenty-four hours a day, but I can literally feel cold wind blowing through my living room curtains while the window is locked tight.”*
Homeowners often panic and assume their fifteen-year-old windows have suddenly died and need a $20,000 whole-house replacement. But in reality? In nine cases out of ten, the glass and vinyl structure are fine. What has completely died is the cheap builder-grade acrylic caulk around the perimeter and the worn-out pile weatherstripping between the sashes.
How to Tell If Your Window Envelope Has Failed
You don’t need an expensive thermal imaging camera to know if cold air is leaking into your home. Here are three quick practical tests you can do yourself this afternoon:
1. The Dollar Bill Grip Test
Open your window sash, place a crisp dollar bill across the bottom sill or side jamb, and lock the window down on it. Now, try to pull the bill out. If the weatherstripping is healthy and resilient, the bill should hold tight and offer strong resistance. If the bill slides out effortlessly without tearing, your compression foam or fin-seal has flattened out and cold winter drafts are pouring right past it.
2. The Candle or Incense Smoke Drift
On a windy day, turn off your HVAC fan so indoor air is still. Light an incense stick or candle and slowly trace the outer casing and the meeting rail where the two sashes lock together. If the smoke suddenly flutters or blows sideways, you have active infiltration through cracked perimeter sealant.
3. Visible Exterior Caulk Separation
Walk around the outside of your home and look closely at where the window frame meets brick, stone, or siding. If you see cracks, peeling strings of sealant, or gaps wider than a dime where the caulk has pulled away from the masonry, rainwater and freezing air are getting directly into your wall cavity.
Why Hardware Store Silicone Often Fails in the Midwest
A lot of DIYers head down to the local hardware store, buy a $5 tube of standard 100% silicone or painter’s latex caulk, and smear a bead over the old cracking joint. That almost always fails within one season. Standard silicone doesn’t bond well to old residue, and cheap latex shrinks as water evaporates out of the formula.
At CapaHome, we take the time to strip away the brittle, decayed sealant down to clean substrate. We clean the joints with denatured alcohol and pump in commercial-grade, high-movement polyurethane sealants that cure with atmospheric moisture and stay flexible down to -30°F. Then we replace collapsed sash pile with heavy-duty finned weatherstripping custom-sized to your window frame channels.
Stop Paying to Heat the Outdoors This Winter
A professional re-caulking and weatherstripping overhaul can lower winter draft complaints and trim heating bills immediately. Contact CapaHome LLC at (224) 434-0915 or book an inspection through our contact page.
