- You'll want to be careful when purchasing your caulk. Choose a caulk that is recommended specifically for use on vinyl siding. Use a water-based caulk designed for outdoor use around windows and doors. Oil-based caulks are not recommended for use on vinyl due to lack of flexibility. You will also need plenty of paper towels or old rags or towels for clean up.
- Apply the caulk when the temperature outside is between 40 to 80 degrees. Extreme temperatures will interfere with the bonding between the caulk and the surfaces being caulked. Avoid applying the caulk within 12 hours of expected rain. A cool, dry late summer or early fall day will be most likely to provide optimum conditions. Allow an entire day to get the job done right the first time. You won't want to have to caulk again a year later.
- Make sure the surfaces being caulked are clean and dry. Use a broom and rag or towel to wipe away dust and debris. If the surfaces are at all damp, allow them to dry completely before beginning. Fill any large gaps first with spray-in foam rather than caulk, and give it plenty of time to dry. Trim away excess foam with a razor blade after it is completely dry. Begin to caulk in an inconspicuous place, like along the top of a window where you won't easily see the caulk, to give yourself an opportunity to get the hang of caulking. Hold the caulk gun at about a 45-degree angle, pulling it toward you as you squeeze the trigger. Wipe away any excess caulk on surfaces and your hands before it dries with a damp paper towel or rag.
