Most gaps in exterior wood trim are caused by poor installation of the trim or shrinkage in the wood trim. Gaps in exterior wood trim must be repaired with a material that flexes with the natural expansion and shrinkage of wood. Repair material should not create another gap or crack. Before deciding to fill a gap in exterior trim, determine if it is possible to remove and match a piece of the trim--cutting a new piece to eliminate the gap. In most cases, removal and trim replacement is not cost efficient. Repairing by filling the gap with a silicone-based caulk is usually the preferred course of action.
Things You'll Need
- Putty knife
- Utility knife
- Exterior silicone-based caulk
- Caulking gun
- Towels and rags
Scrape dirt, paint and old caulking out of the gap in the exterior wood trim, using a putty knife, screwdriver or utility knife.
Snap the caulk tube into the caulk gun. Squeeze the trigger to fill the gap with caulk.
Smooth with a wet sponge, small putty knife or your finger while the caulk is still pliable. Tidy with a towel.
Follow manufacturer's instructions for caulk cure time and temperature installation parameters.
Finish with primer and paint to match.
Tips & Warnings
- This process can also be followed for gaps created by a loose trim piece, window trim gaps, fascia board and soffit gaps or siding issues.
- Do not use wood filler to repair a gap in exterior wood trim as it shrinks, falls out and cracks in extreme weather conditions.
- Photo Credit glazier image by Greg Pickens from Fotolia.com
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