Hardiplank siding is a long-lasting, fireproof building material that resembles natural wood. Because it is a concrete-based product, it cannot be stained in the traditional sense. However, there are products on the market that give fiber cement board a stained look. By taking special care during the application process, you can replicate the look of natural stained wood with your Hardiplank siding.
Finish the board prior to installation. To achieve the appearance of stained wood on Hardiplank, your best bet is to finish the siding before it is installed on your house.
Lay the boards out flat, wood-grained side up. Fiber-cement stain is a product that replicates the look of natural wood by pooling in the imprinted grain pattern on Hardiplank. For this reason, the stain works best when it is applied to boards laid down flat.
Dust off the boards. Make sure the Hardiplank is completely clean and free of contaminants prior to applying stain. Hardiplank generally comes form the factory with a coat of primer, so there is no need to prime prior to applying stain.
Spray on the first coat of stain. A pump-up sprayer works well for applying fiber-cement stain. Adjust the nozzle so that the spray pattern is just slightly wider than the width of a single piece of Hardiplank. Start at one end of the board and work your way down to the other. Try and create as consistent a spray pattern as possible.
Re-coat as necessary. Generally it is better to apply multiple light coats of stain. Follow the stain manufacturer's instructions regarding dry time between coats. You should start to notice the build-up of product in the grain pattern after the second or third coat. Each coat of stain will darken the board. Re-coat until you achieve a color and depth you are pleased with.