How to Caulk a Deck
- 1). Vacuum the deck surface thoroughly, with extra attention on the boards that require treatment. Soak a mop in a mild cleaning detergent and clean any visible trace of dirt or grime. Allow the deck to air dry.
- 2). Cut off the plastic tip on a tube of silicone caulk with a pair of scissors, creating an opening to dispense a bead of caulk roughly 1/4-inch wide or less.
- 3). Insert a stiff wire into the opening of the tip to puncture the foil seal inside. Load the entire cartridge into a caulking gun, with the tip pointing away from the trigger.
- 4). Align the tip of the gun with a seam between the deck boards. Hold the gun at a 45-degree angle. Insert the tip into the targeted space and steadily squeeze the trigger to disperse the sealant.
- 5). Draw the gun along the seam to fill it completely. Quickly wipe up excess caulk with a damp rag before it hardens Repeat the same procedure on other cracks in the deck. Allow the silicone to cure for 24 hours.
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