How to Caulk Decks
- 1). Vacuum the deck thoroughly, focusing most on the floorboards that require treatment. Mop the wooden surface with a mild detergent to clean any visible traces of dirt or grime. Allow the deck to air-dry.
- 2). Snip the plastic tip on a cartridge of silicone caulk with scissors to create an opening roughly 1/4 inch wide or less.
- 3). Puncture the foil seal within the tip with a nail or stiff wire. Insert the cartridge into a caulking gun, with the tip pointing away from the trigger.
- 4). Align the tip of the gun with a gap between the wooden deck boards. Holding the gun at a 45-degree angle, insert the tip into the space and squeeze the trigger to dispense the sealant.
- 5). Draw the gun along the length of the seam to fill it evenly. Wipe the excess caulk quickly with a damp rag to prevent it from solidifying. Repeat the same method for any additional cracks in the deck. Allow the sealant to cure for 24 hours.
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