How much does a window seal repair cost?

Although most window seal repairs are between $70 to $120, on average, the cost of a seal repair for your windows will depend largely on what type of window repair you need, the size of the windows and how many windows you need to fix.

Many contractors will give you a discount if they need to repair multiple windows at once and can give you a free estimate before they begin.

Sash replacement

If you want to maintain the insulating integrity of a window with a damaged seal, it may be necessary to replace the window sash. The term sash refers to everything contained within the window frame, including the rails, stiles, gasket, glass and gas (such as krypton or argon).

Many factors affect the cost of window glass replacements, explains Joe Puggioni of Weedsport Window and Glass in Weedsport, New York. These include the type of window frame, the distance of the window from ground level, the size of the window and the type of glass (internal grid, low-e, etc.). It's difficult to provide average costs for sash replacement, says Puggioni, which is why it's important to get a free estimate for your situation.

Here are some examples of cost from Weedsport Window and Glass:

Labor costs

To replace the sash, your contractor needs to consider materials as well as labor costs -- and labor-intensive jobs can raise the total window repair costs.

An example would be an old Andersen milled unit without access to moldings. The only way to replace the glass is to cut moldings with a straight edge and razor knife where the simulated moldings appear to be, says Puggioni. Specialty situations like this will increase the cost.

Replacing broken glass

You may just need a glass replacement, or you might have to re-do the whole thing to make sure your windows are properly insulated.

Replacing broken glass in a double-paned window will cost around $170 to $180, depending on where you live.

Removing moisture

Defogging might cost anywhere from under $100 to several hundred dollars, depending on the company, your geographic location and the type and number of windows you want to be defogged.

Defogging is a newer technique to eliminate unsightly moisture that has collected between factory-sealed double- or triple-paned windows. The pro drills a small hole in the glass, cleans and dries the condensation off of the interior, and reseals the hole to prevent future fogging.

The look of your window will improve, but defogging is simply an aesthetic procedure and will not replace the gases or return your window to its former thermal resistance (known as an R-value).

Sometimes, a simple window repair isn't possible or costs more than replacing the entire window. In this case, you may need to remove it and replace it with new windows. 

Replacing a window will run you about $135 to $145 on average for a single-paned window, and $185 to $250 for double-paned window.

A sealed window is typically a triple or double-paned window that has been factory sealed with gases injected between the panes. Also known as insulated gas units (IGUs), these gas-filled windows are much more common than single-paned glass windows in homes built in recent decades.

According to the U.S. Department of Energy, gas fills in windows improve energy efficiency, which — along with insulated doors and walls — can ultimately reduce your utility bills. The gas filling the space between the panes of IGUs is usually either krypton or argon. These slow-moving gases permit less convection than oxygen, so their presence helps improve the thermal efficiency of your window. The gases limit heat transference and more effectively insulate your home against summer heat and winter cold.

Gas-filled windows can leak as much as 1% per year, slowly reducing their efficacy over time. Even so, they should still provide good insulation for 20 years or more after installation.

Damage to your windowpanes can breach the glass seal, allowing the gas inside to leak out and eliminating the insulating power of the triple- or double-paned window. If you can see the actual damage to the seal or glass, or notice moisture or condensation gathering between the panes, it may be time for a professional to help replace the panes or fix the seal.