Caulk bubbles can originate from trapped air in the cartridge, caused by manufacturing or air leaking in through an uncovered cartridge tip, or from trapped water underneath the caulk that is vaporizing under the surface of the film of the caulk.
– Be sure to keep the tip of the caulk cartridge covered at all times that it is not in use to prevent air seeping in.
-With any caulk application, make sure the area to be caulked is clean and free of moisture by wiping it down with a dry cloth. This prevents water from getting trapped underneath.
-Make sure you smooth the caulk into a consistent, seamless beading before letting it cure. You don’t want to leave any voids for air or moisture to get in.
If it has been an hour or less since you caulked the area that has bubbles, you may still be able to smooth or tool it out a bit. Any later than that and you will have to remove the bubbled caulk and start over.