How to Replace Window Caulking

As fall approaches and the weather starts to get cooler, it's a good time to think about replacing the caulking around your windows. Last winter were any of your rooms drafty? Did the curtains move when the furnace wasn't on? These are signs that your window caulking isn't doing its job anymore and you should replace it. Fall is a good time to do this job, since caulking works best when it's applied in temperatures between 50 and 70 degrees F, so it has time to dry thoroughly without drying out too quickly or potentially freezing before drying properly. Here's how to go about replacing your window caulking.

Difficulty:

Moderately Challenging

Instructions

Things You'll Need

• Caulk remover (available at home stores)
• Window caulk (latex/paintable caulk)
• Caulking gun
• Putty knife or scraper
• Utility knife
• Rubber gloves
• Rubbing alcohol
• Soapy water
• Foam backer rod (possibly)

1. Think about the rooms where you felt drafts or the curtains moved last winter. You can also check for faulty caulking by placing a tissue on the end of a pencil and slowly moving it around the edges of a window. If the tissue moves, there is a draft coming in around the window--and the caulking should be replaced

2. Start by removing the old caulking. You can go at it the old-fashioned way by digging the old caulking out with a putty knife or scraper, but it's easier if you just apply some chemical caulking remover, let it set up and then remove the old caulk after it's been softened. You may need to remove some really stubborn old pieces by cutting carefully along the seams, then using your scraper to dig them out.

3. Clean up any remaining little pieces of leftover caulking using rubbing alcohol and old rags. You need to get rid of all the old caulking for the new caulk to adhere properly.

4. While you're waiting for the alcohol to dry thoroughly, use your utility knife to cut the tip of the caulking tube on an angle about ¼ inch from the end. You will need to use a long, thin nail to puncture the foil covering the caulking at the base of the tube tip.

5. Insert the tube of caulk into your caulking gun and squeeze the handle to apply some pressure to the base of the tube and bring the caulk up to the tip.

6. Start at a corner and push the caulking at about a 45-degree angle along the edge of the window, filling in the seam. Apply steady pressure and try to not lift the caulking gun up until you get to an end of one side of the window.

7. When you get to the end, stop squeezing the trigger of the caulking gun and lift the tube up and away from the window while putting an old rag over the end to catch any caulking that comes out.

8. Clean the end of the tube and move to start applying caulking along the next side.

9. After you've caulked all sides of the window, use a finger dipped in soapy water or an old Popsicle stick or small tongue depressor to smooth the bead of caulking all along the window edge.

Tips & Warnings

• Caulks come in a variety of colors as well as transparent. It's your choice as to which appearance you prefer.

• If you have gaps around your window that are more than ¼-inch-deep or ½-inch-wide, consider inserting some foam backer rod before you apply your new window caulking.

• If you've never used a caulking gun before, you might consider buying a tube of inexpensive caulking to practice with. Using a caulking gun can be tricky.

• Your windows will have small holes (called weep holes) on the bottom. These are there to allow for moisture to escape. Don't fill them with caulk.

• Not all caulks are paintable. If you are planning on painting your house or windows, be sure to choose a paintable caulk. Ask at the home store.