How to Caulk Beneath Siding
- 1). Extend the ratcheting plunger handle of the caulking gun to its open position. Twist the plunger shaft so that the grooved side is facing the top of the gun so it slides free. Load a tube of siliconized acrylic latex caulk into the caulking gun. Push the plunger into the hole in the back of the tube of caulk. Twist the plunger shaft so that the grooved side is facing the bottom of the gun. Pull the trigger of the gun several times until it gets tight. You will hear a clicking sound as the ratcheting mechanism moves the plunger forward. Cut the tip off the caulk tube nozzle off at a 45-degree angle with a utility knife. Squeeze the gun trigger until caulk comes out of the tip. The gun is ready to go.
- 2). Scrape away all flaking paint and loosen all debris from the joints in between the siding using a wire bristle brush and a putty knife. Dust the gaps or joints with a dust brush. Clear away all debris that could adversely effect the adhesive power of the caulk. Use the hose of a vacuum to suck out large concentrations of dust, paint and debris buildup. You want the surface area to be as clean and as sound as possible before applying the caulk. Avoid damaging the siding while cleaning it.
- 3). Stand at one side of the wall. Hold the caulking gun handle with one hand and place your other hand over the nozzle. Place the pointer finger of the hand over the nozzle just over the tip. Squeeze the trigger of the caulking gun. Watch to see when caulking comes out. Move the gun along the gap or joint applying a bead of caulk large enough to fill it. The finger on the tip will drag over the bead of caulk smoothing it into the crack. Caulk all the way across the joint and when the tube runs dry insert another one and continue on. Wipe excess caulk off your finger on a damp painter's rag.
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