I started installing fiber-cement siding in 1998 when it wasn't widely used and fiber-cement trim boards weren't available. The first time I sided a house with fiber cement, I used 1x4 pressure-treated trim boards covered with pieces of the siding. The completed home looked better than its vinyl-clad neighbors — and it survived a direct hit from 2004's Hurricane Charley with no damage.
Since then, I've built, re-sided, and repaired dozens of homes with various brands of fiber-cement; it's an ideal material for southern Florida, where I live and work: It doesn't rot, burn, or attract insects and woodpeckers, and it holds paint better than wood. But the attribute I appreciate most is its wind resistance.
Dust Control
Lately, I've been getting a little more creative with fiber-cement siding and trim by adding details like decorative shingles and gable ornaments. Although these designs look great, they require a lot of cutting, which produces a great deal of dust. Fiber-cement particles can lead to respiratory problems like silicosis, so adequate dust control is critical.
I have several ways of dealing with dust. Most often, I cut outdoors on the breezy side of the house, keeping a length of vacuum hose on the chop-saw exhaust to direct the dust to the ground (Figure 2). If there's no breeze, I may set up a large fan next to the cutting station to blow the particles away from my face. The biggest dust clouds are caused by ripping on the table saw, which I avoid doing whenever possible. If I have to use the table saw, I wear a respirator containing HEPA cartridges.
I suspect that the dust is hard on power tools as well, so I make sure to blow the dust out of my saw motors once in a while, paying particular attention to the switch and brushes. I can tell the brushes need cleaning when the blade brake stops working. When I began using an old 12-inch chop saw to cut siding about five years ago, I thought the dust would quickly destroy the bearings or the motor, but the tool is still going strong.
Cutting Methods
I've tried cutting fiber cement with just about every new tool that's come on the market, including score-and-snap cutters, electric shears, carbide saw blades, diamond masonry blades, hand nibblers, and even an asphalt-shingle shear. All of them work, but none produces as clean a cut as the new polycrystalline diamond (PCD) blades. I buy Tenryu's PCD blades (800/951-7297, www.tenryu.com) for chop, circular, and table saws, and am always surprised at how long they last. One great advantage of the PCD blades is that you can make stacked cuts limited only by the saw's depth of cut. This is important when making shingles.
For scrollwork I use a jigsaw fitted with a carbide-grit blade, the type commonly used for cutting ceramic tile. Each blade will cut about 20 feet of 1-inch-thick material before I have to replace it. I make large-radius cuts freehand on the table saw with the blade set so that it just barely cuts through the siding, which reduces airborne dust and prevents binding.
Fasteners
Because fiber cement has such a long life expectancy, I use only stainless-steel ring-shank nails; they offer superior corrosion protection and withdrawal resistance. Collated stainless-steel siding nails — which are typically .090 or .099 inch in diameter — tend to crumple as they're driven into cement board, so I use Hitachi's 2-inch-long-by-.113-inch-diameter nails for siding, and 23/8-inch-by-.131-inch nails for trim. My suppliers special-order these thicker nails; lead times run a week at most.
When a ring-shank nail crumples, I don't even try to pull it out. The holding power of the ring shank combined with the friability of fiber cement almost always results in damaged siding or trim. Instead, with a chisel I nick the shaft of the nail where it enters the siding and bend the nail back and forth until it snaps. Then I hammer in any part of it that's left. If I need to remove a piece of siding that's been nailed, I drive the nails thru the siding with a punch.
Trim boards are less dense than siding boards. This keeps their weight down and makes nailing easier. It also means that removing a damaged piece of trim without destroying it is impossible — so I just plan on replacing trim boards when they have to be removed, for whatever reason.