How to Install Hardboard Siding

Hardboard siding is a composite building material made from wood resin and wax.

Hardboard siding is sold in panels that resemble a natural wood product.Hardboard siding is sold in panels that resemble a natural wood product.
It is an economical siding product sold in sheets of planks. Hardboard siding emulates the look of a natural wood product. Its main drawback is that it is extremely susceptible to moisture damage and fungus growth. Proper installation is essential to ensure that moisture can't get behind the boards and cause warping and rotting. Installation is not particularly difficult relative to other siding products, but it absolutely must be done right.

Paint the back of the board with 2 even coats of a good quality exterior primer. Use a paint brush, roller, or sprayer to completely coat the backsides of all hardboard panels prior to installation.

Determine your starting point and mark it with a pencil. Hardboard siding should begin at least 6 inches from the ground, higher if possible. Keep in mind that water is not your friend and the boards closest to the ground are the most exposed to moisture. Use a level and a chalk line to extend a base line around the perimeter of the house.

Fasten corner pieces. Install a 1 inch by 2 inch strip of wood vertically, flush to the corner of the house. On the other side of the corner use a 1 inch by 3 inch strip. This wider piece will overlap the exposed side of the smaller piece to create an even, complete corner.

Install your hardboard panels. Start in one lower corner. Drive corrosion-resistant nails through the panels and into the wall studs behind. Position the nails at a distance 16 to 24 inches apart, depending on the stud spacing, typically 16 inches. Drive the nails so that the head lies flush over the surface of the hardboard. Over driven nails will create a moisture-vulnerable point. Fill divots created by over driving nails with polyurethane caulking.

Where necessary, use a circular saw to cut panels to size. Cover the house from the foundation to the roof eaves.

After you've got the siding installed, run a bead of caulking along all joints where the siding meets the trim pieces: along the corner pieces and around windows and doors.

Things You Will Need

  • Tape measure
  • Pencil
  • Level
  • Chalk line
  • 1 inch by 2 inch strips of lumber
  • 1 inch by 3 inch strips of lumber
  • Corrosion-resistant nails
  • Hammer
  • Circular saw
  • Polyurethane caulking
  • Caulking gun


  • The essential thing to keep in mind with hardboard siding is that you've got to keep it from being exposed to sources of moisture. Keep the siding sealed and adjust sprinklers so they are not spraying it.
  • It is recommended to treat hardboard siding with a fungicide every couple of years. Refer to the manufacturer's specific recommendations regarding the best products to use.

About the Author

Robert Howard has been writing professionally since 2004 and writes a weekly column for the "Synthesis," a Chico, Calif.-based newspaper. He maintains a blog and has published articles and works of fiction in a variety of different print and online magazines. Howard holds a Bachelor of Arts in visual arts from the University of California, San Diego.