How to Seal a Cracked Window Frame

Windows and their surrounding frames help keep your home protected against water damage.  Moisture, when it seeps in through cracks, gaps, and holes, can wreak havoc on wooden frames and if this problem isn’t fixed promptly, then you could experience things like structural damage because moisture will weaken the integrity of construction materials.

installing and sealing window frames

Why Seal Window Frame Leaks?

Window leaks are common as there many parts to a window.  Windows—and window frames—are constantly battling the elements.  Wear and tear can cause gaps and cracks to form and invite moisture to seep in.  Tackle this problem as soon as you can, otherwise you could be faced with more repairs with an expensive price tag.

You could also face other problems as consequence of a cracked window frame:

-Siding issues:  yes, a cracked window frame can lead to issues with your home’s exterior siding.  Water will always travel the path of least resistance and sneaking its way through a crack in the frame and underneath the siding is a common side effect of damaged windows.  This will mean moisture under the siding which can then rot the sheathing, warp the siding panels, and ultimately make the siding and sheathing deteriorate quicker.

-Energy costs:  it’s not just water that can get in through cracked window frames.  Air will flow through any gaps in a window frame and although this isn’t as damaging as water, drafts will affect the overall energy costs of your home.  A drafty, cracked window frame means your home will have to work harder to heat or cool the inside and internal temperatures will struggle to be both comfortable and steady.  You’ll not only notice the drafts in your home but you’ll realize that your energy bills are much higher than they need to be.

-Resale value: potential buyers look for a home that’s in good condition.  Cracks in a window frame not only hurt your home’s curb appeal, but drafts, moisture damage, structural damage, warped siding, and other issues are bound to capture the attention of a homebuyer during a walkthrough.

How to Seal Your Window Frame

Sealing your cracked window frame is easy.  You don’t have to have any special skills or tools or be a master DIYer.  Really, all you need is the right kind of sealant.

sealing a window frame

Step One: Finding the Leaks

Your first step is finding where the window is leaking.  This won’t be too difficult as cracks in a window frame can be rather obvious.  Some cracks are harder to detect.  If you know your window has a crack but you can’t find where it is, do the draft test.  On a cold, windy day, check the windows in your house with your hand to feel for where the drafts are originating from.  If your windows are old, you’ll probably have to check all the windows in your house to make sure all of them will be sealed.  You can try other simple DIY methods like using a temperature gauge near the windows or even lighting a stick of incense to help indicate drafts.

Step Two: Choosing the right sealant

There are numerous types of sealants for all sorts of different applications.  The one you want to correctly seal your windows will be made for exterior window perimeter joints.  Sealants that are comprised of a neutral cure silicone adhesive work well for bonding exterior cracks of window frames.  Also try to match the sealant product to the material of the window.  Caulking products are designed for specific uses and materials like wood, metal, or plastics.

Step Three: Prepping to Seal

To successfully seal cracked window frames, you’ll need to first remove any old, deteriorating sealant.  Old sealant is likely the culprit behind the leaks and cracks and for the new sealant to be effective, you’ll need to take it all off.  Old sealant can be difficult to remove as it often dries and bonds to the surface.  If that’s the case for your window frame, take a heat gun and small utility knife to loosen it and scrape it off.

Next, clean the surface before sealing it.  A clean surface will mean that the caulking will bond better.  Use an alcohol-based cleaner as alcohol will act as a solvent, which will break down any remaining old sealant and make it easier to wipe it off.

Step Four: Apply the Sealant

Finally, apply the sealant.  Use a caulking gun to make this step easier and follow the manufacturer’s instructions on the label.  Insert the sealant tube into the caulking gun and cut the tip at an angle for ease of application.  Remove any excess sealant with a joint shaping tool.  Allow the sealant to cure.

Fixing Cracks in Window Frames

New caulking will help fix the cracks in your window frames, but a better long-term solution will be to invest in new windows.  Window replacements are a big investment but will bring you plenty of advantages like lower energy costs, no more drafts or air leaks, a more comfortable temperature inside of your home, and a major boost in resale value and curb appeal.

Feldco is the most trusted company for window replacement with over 500,000 delighted customers across the Midwest.  Get a free quote now!

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