How to Fix the Gaps in Exterior Trim
Exterior trim around doors and windows needs to be caulked to fill any gaps between the trim and the siding behind the trim. While properly designed exterior caulking is designed to last for many years, summer heat and winter cold may cause it to expand and contract, finally creating gaps and cracks. Fill those gaps with new caulking as soon as possible to prevent water from getting behind the trim and into the walls, causing harm and maybe expensive repairs.
Rank a stepladder, if needed, beneath the window, door or other area with gaps in the exterior trim. Climb the ladder and inspect the caulking between the trim and the shingles, searching for any areas which are cracked or where the caulking may be lost.
Cut away any damaged or cracked sections of caulk with a sharp utility knife.
Place a tube of exterior caulk into a caulk gun and squeeze the trigger to engage the bail. Cut off the tip of the tubing nozzle in a 45-degree angle by means of a utility knife.
Rank the caulk gun so the angled tip of the nozzle is level against the gap to be filled. Depress the trigger on the caulk gun before caulk begins to squeeze from the nozzle. Slide the caulk gun and the trim, then holding the angle of the nozzle flat contrary to the boards until you have filled the gap completely.
Wet your finger and gently wipe the caulk in the gap to give it a smooth, curved look. Wipe away any excess caulk. Fill any low spots or staying gaps with additional caulking until the gap is totally full of a smooth, clean, curved bead of caulk.
