Fiber Cement Siding
Concrete Home > Building Systems > Fiber Cement Siding
Fiber-cement siding has the look of wood siding but has a lower cost and lower maintenance. Market share is approaching ten percent, according to manufacturers. Additional benefits include resistance to termites and fire. Fiber-cement siding will not rot, buckle or warp and holds paint for several years longer than conventional wood siding.
Moisture resistance is a concern, but problems can be avoided if the siding is installed correctly and properly treated. Labor is a bit more intensive, and proper precautions should be taken when cutting fiber-cement siding.
Fiber-cement trim pieces are straighter than wood siding, so less time has to be spent bowing the trim in alignment. Fiber-cement siding is much heavier than wood siding. However, it is flexible, so carrying it on its edge rather than the flat is recommended. Finally, a wavy frame will not be hidden by fiber-cement siding, unlike wood siding. The lumps will show through.
Either by hand or by coil nailer, the one thing to avoid when nailing is overdriving the fasteners. While coil nailers are faster, the drivers in the guns can be worn out faster, depending on usage. Setting the nail head below the surface decreases holding power. Also, take notice of the nails you use. Make sure you use corrosion-resistant roundhead nails. Fasteners should be driven into framing members. Most kinds of lap siding are bound at the top and bottom. A note of caution: Blind-nailing is not recommended in high wind areas. If you are going to blind-nail, use large nail heads and place them just above the lap line.
Typically, wooden vertical trim pieces were used when using bevel siding. This gave the siding something to run into. But using wood is not practical when you’re using a material that is going to last as long as fiber-cement siding. Fiber cement trim board is available in varying sizes, from 7/16" to 3/4" to 1". Vinyl corner trims are another way to get around using wood.
Manufacturers recommend joining fiber-cement lap siding over a stud. Make sure to leave a 1/8" gap between the siding and the edge of the wood casings and corner boards. (That’s so the wood can move.) There is no need to paint or seal end cuts.
Fiber-cement siding can be installed over foam insulation board, as on an ICF house, but problems can occur during installation. Extreme caution must be taken to ensure proper installation.
Top row, L-R: Shingles, Smooth Beaded, Smooth
Bottom row, L-R: Vertical, Textured Beaded
Fiber-cement siding holds paint exceptionally well, usually 7-15 years. Some manufacturers make their siding available pre-primed, but still offer raw siding. This allows you to put your own primer and topcoat on. Before painting, make sure you thoroughly wash your siding. Also, allow it adequate time to dry. Dirt and mildew are liable to stick to flat paint. Satin topcoats have a higher chance of looking blotchy than flat ones, so make sure to do a good job on your priming. Oil-based primers are not recommended, but oil-based topcoats are acceptable over latex primers. Prolonged surface exposure to water causes degradation, so it is important to paint your siding within 90 days of installation. Always make sure to follow the manufacturer’s specs.
Given the proper care, fiber-cement siding can give your home the look of wood with the protection, low maintenance and lasting power of cement.