How to Water Proof Siding on a House

Remove any mildew stains from the wood siding before waterproofing it. Begin by mixing 1 cup of cool water with 3 cups of household bleach in a clean bucket. Wear rubber gloves when handling bleach.

Spray the ground and foliage below the mildew-stained wood siding with water to inhibit bleach damage. In addition, cover the wet vegetation with drop cloths.

Dip a scrub brush’s nylon bristles in the bleach solution. Scrub the mildew-stained wood siding panels with the solution until the dark mildew spores disappear. Stand on a ladder to access upper regions of the siding.

Rinse the dead mildew spores and bleach off the wood siding panels. Using the garden hose, spray water straight at the siding panels to avoid trapping water up underneath them. Stand on the ladder to rinse upper regions of the siding.

Remove dirt, dead insects, bird droppings, and other grime from the wood siding using plain water. Fill another bucket with fresh water, and then scrub each wood siding plank with the water using the scrub brush. Stand on the ladder to clean upper regions of the siding, and frequently replace the water.

Allow the wood siding to air-dry for two dry days before waterproofing it.

Put on the rubber gloves and a protective breathing mask designated for use around pesticides. Drape the drop cloths over any vegetation near the wood siding.

Stir a water-repellent preservative with a wooden mixing stick for 1 minute. Pour the water-repellent preservative into a paint tray.

Coat the ends of all wood siding panels and joints between the panels with the water-repellent preservative using a synthetic bristle paintbrush. In addition, apply the product to areas of the siding below doors and window frames, since these regions are extremely vulnerable to moisture. Liberally apply the water-repellent to these regions until the wood stops accepting it. Stand on the ladder to access upper regions of the siding.

Saturate each siding panel with the water-repellent preservative using the paintbrush. Focus on waterproofing one 3-foot-wide section of wood siding at a time, working from the top siding panels downward. Thickly apply the product until the wood siding stops accepting it. Stand on the ladder to access upper portions of the siding.

Let the water-repellent preservative cure for three dry days.