Fibre cement board is a relatively new, energy-efficient type of siding. This type of siding replicates the look of natural wood, while providing great durability and economy. Fibre cement board is susceptible to water damage; as a result, it is important to completely seal the board before it is applied to the exterior of the house. Painting fibre cement board is one of the simplest and most effective ways to seal the board. All sides, including the end cuts, of fibre cement board should be primed. The primed board can be installed on the house, and then two coats of exterior paint can be applied to the exposed surface of the product.
Inspect and clean the fibre cement board. It is important that the siding is completely free of any dust or dirt that may have accumulated during storage. Lay the boards out and use a broom or hand brush to sweep them down.
Prime the back of the boards. Lay the boards face down, either on the ground or on saw horses, and apply a good quality exterior primer. Use a paintbrush, roller or sprayer to apply the primer. A single coat of primer should seal the board. Let the primer dry according to the manufacturer's instructions.
Turn the boards over after the primer has dried. Then apply primer to the front and sides of the boards. In addition, prime the exposed ends and end cuts. Allow the primer to dry completely.
Install the primed fibre cement board onto the exterior of the house. Follow the manufacturer's instructions regarding fibre cement board installation.
Apply the first coat of paint to the siding. Select a good quality exterior paint. Apply the paint with a paintbrush, roller or sprayer. Start at one corner of the house and work your way out. As you work, brush in or remove any running paint. Completely cover the nails and seams; these areas can be particularly vulnerable to moisture. Follow the manufacturer's instructions regarding drying time between coats.
Apply the second coat of paint to the siding.