Should you caulk around windows on the outside?

Yes, in most cases you should caulk around windows on the outside. Sealing the joint where the window trim meets the wall helps keep rain and drafts out. Just don't seal the small drain openings that let water escape.

Outside caulk takes a beating from sun, rain and heat, so it cracks and pulls away over time. In a rainy place like Chattanooga, a cracked joint can let water get behind the trim, where it may rot wood or soak into the wall. Look at your window caulk each spring and fall.

To do it right, scrape out old, cracked caulk with a putty knife. Clean the joint and let it dry. Use an exterior-grade caulk made for the materials you are sealing, and choose a paintable one if the trim gets painted. For gaps wider than about a quarter inch, press foam backer rod in first. Run one steady bead and smooth it with a wet finger or tool. Pick a dry day with no rain in the forecast, and follow the temperature range printed on the tube.

Some spots should stay open. Many window frames have small weep holes along the bottom edge that drain water out. Some window makers also say to leave gaps at the bottom of the trim. Sealing those can trap water inside the frame, so check the instructions for your windows when in doubt.

Caulking outside gaps at windows and doors is part of every Fortress Spring Refresh visit.