Window Repair

Most failed windows don't need replacing.

They need the right diagnosis. A fogged pane, a sash that won't stay up, and a cold draft are three completely different failures — with three completely different costs. Knowing which one you have is most of the money.

What's actually wrong

Start by locating the failure: the glass unit, the moving sash, or the frame and its flashing. Almost every bad repair decision starts by guessing wrong here.

Fogged or cloudy glass

The seal on an insulated glass unit has failed. Moisture is now inside the sealed cavity, between the panes, where no amount of cleaning will reach it.

Windows that won't stay up

A broken sash balance or spring. Extremely common in double-hung windows, and usually one of the cheapest repairs on this list.

Drafts and cold edges

Often failed weatherstripping or a compromised perimeter seal rather than the glass itself — frequently fixable without touching the window.

Cracked or broken pane

In many frames a single pane or the whole insulated unit can be replaced while the existing frame stays in place.

Sticking or binding sashes

Swollen wood, paint buildup, a racked frame, or worn hardware. Diagnosis matters: a racked frame points at a structural cause.

Water intrusion at the sill

Usually flashing, caulk, or drainage — not the window. Chasing the glass here fixes nothing and the damage keeps compounding.

Fogged glass, explained

The window isn't dirty. The seal is broken.

A modern window is an insulated glass unit: two panes separated by a spacer, sealed at the perimeter, with a desiccant inside the spacer to absorb the small amount of trapped moisture. When that perimeter seal fails, humid outside air cycles into the cavity. The desiccant eventually saturates, and moisture starts condensing on the inner surfaces — where you can see it and cannot reach it.

This is why cleaning never works, and why the fog often appears and disappears with temperature. It also means the unit has lost much of its insulating performance. The good news: in many frames the insulated unit alone can be replaced while the existing frame, sash, and hardware stay exactly where they are.

Repair or replace?

An honest contractor will tell you when the frame is the problem. This is the framework they're using.

Repair usually wins

  • The frame is sound and square
  • Only the glass unit or hardware has failed
  • The window is original to a historic or architecturally matched opening
  • Sash balances, weatherstripping, or locks are the actual complaint
  • You need one or two openings addressed, not the whole house

Replacement earns its cost

  • Frames are rotted, racked, or no longer holding square
  • Single-pane units where comfort and energy use are the real complaint
  • Repeated failures across many openings of the same age
  • Parts for the hardware or frame system are discontinued
  • You're already opening the wall for other work

What actually drives the cost

Glass typeLow-E coatings, laminated and tempered safety glass, and argon fill each change the price of an insulated unit.
Size and weightLarge units may require two installers or lift equipment, which drives labor more than material.
Access and heightSecond-story and hard-to-reach openings add setup, staging, and time.
Frame materialWood, vinyl, aluminum, and clad frames each have different repairability and parts availability.
Historic or customTrue divided lites, curved glass, and non-standard sizes are fabricated to order.
Scope of the real problemIf the underlying issue is rot or flashing, the honest repair is larger than the glass.

What to ask before you agree to anything

  1. Is the failure in the glass unit, the sash, or the frame — and how did you determine that?
  2. Can the insulated glass unit be replaced without replacing the entire window?
  3. What is the warranty on the glass unit versus the labor, and who honors it?
  4. If there's moisture damage, what's the source, and is it fixed by this work?
  5. What's the lead time — are units stocked or fabricated to order?