Caulking Windows – How to Caulk Windows

How to Caulk Windows to Prevent Cold Air Drafts from Entering Your Home

By Mark J. Donovan

Window caulking plays an important role in keeping your home energy efficient and warm during the winter months.

Every year you should inspect the outside of your home and caulk exterior windows and doors as required.

Caulking windows is simple and inexpensive to do. All it requires for tools is a caulking gun, a utility knife, a long thin screwdriver and a ladder.

In the fall, when the weather is still above 40o Fahrenheit, you should inspect the exterior of your windows and look for any open seams around the windows where the house siding abuts the window frame.

If you do find open seams around the window frame apply window caulking.

Make sure to use a window caulk that is designed for exterior applications. An elastomeric Acrylic Latex Caulk with Silicone works best as it is extremely durable and flexible. A urethane caulk also works well for outdoor applications.

Window Caulking Types

Window caulking comes in a variety of colors, however I prefer to use a clear caulk as it works well with any house paint color.

Many caulk vendors offer clear caulk that comes out white when it is applied, but then dries clear, so don’t be alarmed when you see white caulk coming out of a tube of caulk that’s labeled clear.

Painting Window Caulking

If you prefer to paint the window caulk make sure you select a caulk that is paintable. Silicone based caulk is not paintable.

Window caulk is also sold by a year rating system. For best results with exterior applications, I prefer to use window caulking rated for at least 35 years.

Caulk meant for exterior or wet applications is also available with a mildewcide integrated into the formula to retard mildew growth.

How to Caulk Windows

To caulk exterior windows make sure the window frame and the house siding adjacent to the window frame are clean and dry.

Then, with the tip of the caulk tube cut at a 45 degree angle, use a caulking gun to apply a 1/8 to ¼ inch wide bead of caulk around the window frame.

Make sure that the outside temperature is above 40o Fahrenheit. If necessary use your finger to press the window caulking into the seam and smooth the bead.

Also make sure to caulk around your exterior doors as well.

Caulking Exterior Windows

Finally, it is important to remember to check the door and window caulking annually as caulk can dry out, the home can settle, and doors and windows can contract or expand.

All of these factors can cause new cracks or seams to open up around the door and window frames.

For more information on Installing Replacement Windows and Interior Window Trim

  • See the Installing a New Window Ebook from  The Installing a New Window Ebook provides easy to understand, step-by-step instructions, on how to remove an old window and install a new one. Pictures are included for every key step in the process.


  • See the Installing Interior Window Trim Ebook from  The Installing Interior Window Trim Ebook provides easy to understand, step-by-step instructions, on how to install interior window trim around a window. Pictures are included for every key step in the process.

Installing Window Trim eBook

Related Information on How to Caulk Windows

Additional Window Installation and Maintenance Resources from Amazon

Get Free Window Price Quotes, No Obligation!

Fill out our 3-5 minute quick and easy form, and receive a free price quote on windows from one of our prescreened and licensed window contractors. This process is free and there is no obligation to continue once you receive your window replacement price estimate.