Drafty Window Replacement in Frederick, MD
Cold air around windows in winter is one of the most common comfort complaints in Frederick homes. We diagnose where the air is actually entering — sash weatherstripping, perimeter frame seal, or glass seal failure — and fix the right thing.
Where Drafts Actually Come From
A draft near a window is not always a window problem — it can be a wall cavity problem, a gap behind interior casing, or air moving through a failed perimeter seal rather than through the window unit itself. Diagnosing correctly before ordering replacement windows matters.
The most common actual sources: worn or compressed weatherstripping around double-hung sashes allows air to move around the sash even when the window is locked. Deteriorated perimeter caulk between the window frame and the rough opening allows air to enter the wall cavity and exit around interior trim. Failed balance hardware on double-hungs can cause sashes to not fully close and seat against weatherstripping. And a failed IGU seal — which primarily causes fogging — also allows the dry air insulating layer to escape, making the glass itself less effective at blocking radiant cold.
We use physical inspection and, where useful, a simple hand-test or flashlight test to identify air pathways before recommending a solution. Sometimes weatherstripping replacement or perimeter recaulking solves the problem without window replacement. When the frame is deteriorated or the weatherstripping geometry itself is compromised, full window replacement is the right answer.
Fixing Drafty Windows — Our Approach
Inspection First
We assess the window unit, weatherstripping, perimeter seal, and frame condition before recommending anything. A draft near a window that is caused by a gap behind the casing does not require a new window — it requires sealing the rough opening cavity.
Weatherstripping vs. Replacement
If the window unit itself is structurally sound and the draft is isolated to deteriorated weatherstripping, we may recommend weatherstripping replacement as a lower-cost option. If the frame is warped, the sash does not seat properly, or multiple failure modes are present, window replacement is the right answer.
Proper Installation Sealing
Replacement without proper perimeter sealing recreates the problem. We fill the gap between the window frame and rough opening with low-expansion foam, caulk the exterior perimeter, and confirm the installation is airtight before finishing trim work.
Performance Verification
After installation, we verify that the draft path is eliminated. If the home has a blower door test scheduled as part of an energy audit, we can coordinate installation timing accordingly.
Common Questions About Drafty Window Replacement
My windows are new but I still feel a draft. Why?
New windows installed without proper perimeter sealing can still have significant air infiltration. The rough opening gap — the space between the window frame and the framing — must be properly foamed and caulked. If recently installed windows are still drafty, the installation perimeter seal should be inspected before assuming the windows themselves are at fault.
Can caulking fix a drafty window without replacing it?
Sometimes. If the draft is purely from a deteriorated exterior perimeter caulk joint, recaulking may resolve it. If the draft is from within the window unit — sash weatherstripping, operator gaps, or frame warpage — caulking the perimeter will not help. We identify the source before recommending a solution.
How do I know if the cold near my window is radiation or actual draft?
Cold glass radiates cold — this is a normal effect of any window on a cold day, and a lower U-factor reduces it but does not eliminate it. An actual draft will feel like moving air. You can test by holding your hand near window edges, sash joints, and the perimeter casing with the window locked on a windy cold day. If you feel moving air rather than just cold, there is a genuine infiltration pathway.
Stop The Drafts in Your Frederick Home
Call (240) 555-0142 or request an assessment online. We diagnose where air is entering before recommending a solution — so you fix the actual problem rather than guessing.