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FIBER CEMENT BOARD

Jaime Venzor has been in the siding business for more than 15 years. He started out installing mostly vinyl, but now 80 percent of his work is fiber cement. He earned his good reputation with his customers by doing things the right way, and he earned our thanks by sharing some of his knowledge with us. So read on and learn what Jaime thinks are the most important tips.

HOLD THE STARTER 1/4 IN. DOWN

Find your most beat-up pieces of siding and rip them down into 1-1/4-in. starter strips. These strips, installed at the bottom, will make your first row of siding angle out to match the rest of the rows. Snap a line 1 in. above the bottom of the wall sheathing as a guide. Install these fragile starter strips with a 15-gauge trim gun. Snap another line for the bottom row of siding, positioning it so it will hang down an additional 1/4 in. from the starter.

PREASSEMRLE THE CORNERS

Ita lot easier to preassemble corners on a flat surface. Jaime uses 2-1/4-in. galvanized nails in his 15-gauge trim gun. He uses the same size nails to install the corners on the wall. Donuse a framing gun or try to hand-nail the corners together; thata good way to break the trim boards. Also, the trim nails look better where nails will be exposed, especially on a prefinished corner board.

So, if you donhave a 15-gauge trim gun, what a perfect ”to go buy one ($115 and up at home centers).

NAILING RASICS

Fiber cement siding can be hand-nailed, but because itso much harder and more brittle than wood, you have to predrill holes near any edge. You can save yourself a bunch of time by using a pneumatic coil siding nail gun. Unfortunately, a siding gun will set you back twice as much as a 15-gauge trim gun, and itonly half as versatile, so if installing fiber cement isnyour full-time gig, you may want to rent one (about $110 a week). Every manufacturer has specific nailing guidelines, but here are some basic rules:

¦ Use 6d galvanized or stainless siding nails and install them no more than 16 in. apart.

¦ Nail lengths should be chosen so they penetrate a minimum of 1-1/4 in. into the solid wood (wood sheathings like OSB and plywood count toward the 1-1/4 in., but ”sheathings like fiber board and foam don).

¦ Dondrive nails into the siding at an angle.

¦ Fastener heads should be snugged up against the siding, not driven into the surface.

¦ The end of each plank making up a butt joint needs to be fastened to a stud.

¦ Nail butt joints last. That way you can tweak the ends of each plank so the bottom edges line up perfectly.

REMOVE THE PLASTIC LAST

Prefinished fiber cement boards come with a protective plastic coating. To protect the paint from getting scratched during installation, leave the plastic on and make your cuts right through it. Peel away the plastic after the board has been fastened to the wall.

FLASH THE BUTT JOINTS

Caulking butt joints is unnecessary, and some manufacturers prohibit it. However, you should flash behind the joints. You can use metal, house wrap or any other approved WRB (weather-resistant barrier), but Jaime prefers to use 30-lb. felt paper. Iteasy to work with and cheap, and it isnnoticeable if a seam happens to open up a little. Tack it to the wall so it doesnget knocked out of place when you install the second piece of siding.

WINDOWS NEED DRIP CAP AND A GAP ON TOP

Whether or not youinstalling trim boards around your windows, youneed to install a drip cap over the window. Youalso need to leave a 1/4-in. gap (no caulking) between the top of the window and the plank or trim board directly above it. This is to allow any water that may have gotten behind the siding to weep out. Tape the drip cap to the wall, but dontape all the way to the bottom of the drip cap because it will be visible through the 1/4-in. gap. The top trim board will also need its own drip cap and 1/4-in. gap. Treat the tops of doors the same way.

ITS A TWO-MAN JOB WITHOUT SIDING GAUGES

Fiber cement siding is heavy and breaks if itbent too much. Installing this stuff by yourself is tough, but itpossible with the aid of siding gauges. These tools not only create the proper reveal (the part of the siding that shows) between rows but also actually hold the planks in place while you nail. Even if you do just one fiber cement job, siding gauges are worth the money. A pair of the SA902 Gecko Gauges shown here costs about $85 at but cheaper versions are available. Most gauges are adjustable to accommodate reveals from 5 to 8 in.

PAINTED VS. PRIMED

We decided to use a prefinished product in this story, but the other way to go is simple primed siding. That material is primed and ready for you to paint. Here are some facts to consider when making your decision. THE ADVANTAGES OF PRIMED: Primed products cost 50 percent less than prefinished products. On-site painting looks better up close because the touch-up paint and caulked areas arenas noticeable. Primed products are easier and less expensive to install.

THE ADVANTAGES OF PREFINISHED: The color on a prefinished product wonfade nearly as fast. Some finishes come with a 15-year warranty. But the best part of using a prefinished product is that after installation, youdone and not faced with painting an entire house.

CUT THE PLANKS WITH A CIRCULAR SAW

Tons of fiber cement cutting gadgets are available, but most jobs can be handled with just a steady eye and a standard circular saw fitted with a fiber cement blade. If you plan to hang a lot of fiber cement, though, youwant a chop saw with a proper blade that will allow you to cut several pieces at once. You can buy fiber cement blades sized to fit any saw style or size for $20 and up at most home centers. When youcutting this stuff, a dust mask is the bare minimum protection, and this is not a casual warning: The silica dust generated by cutting fiber cement can be bad news for your health!

VINYL MOUNTING BLOCKS WORK BEST

Most fiber cement manufacturers make mounting blocks for lights, electrical receptacles, A/С lines, PVC venting, etc. Jaime prefers to use the vinyl mounting blocks typically used with vinyl siding. Theycheaper and easy to install, and you can cut the proper-size hole in a plastic mounting block with a utility knife or a snips. With fiber cement blocks, you have to use a jigsaw or a hole saw.

MountMaster is one brand of blocks sold at Loweand many lumberyards. Itavailable in more than 25 colors, but you can order paintable blocks if you want an exact match with your siding or trim.

Process of new home construction very responsible and labor-consuming. It is necessary to calculate precisely new home construction. A lot of time of forces to finish the conceived is required.

PAINT, PRIME OR CAULK ALL CUT EDGES

Every time you cut a plank, you create an exposed surface that has no primer or paint to protect it from the elements. If a cut edge is going to butt up against a corner post or trim board, it gets caulked. If the cut edge is part of a butt joint in the middle of the wall, it needs to be painted (try to use factory edges on all butt joints). Planks that have been cut to fit over windows and doors also need paint. Order paint kits and caulking to match both the trim and the siding colors. Your siding supplier should have access to both. Painting kits cost $15 to $20.

THE LOWDOWN ON CLEARANCES

Fiber cement siding is not bulletproof —it will deteriorate if exposed to water for a long time. Itimperative that you honor the proper spacing between the siding and the roof surfaces and between the siding and the horizontal surfaces, such as the ground or cement slabs and decks. Check with your specific manufacturer before you start. Here are some general guidelines.

LEAVE:

¦ 1/8 in. to 1/4 in. between siding and trim

¦ 1/4 in. between siding and horizontal flashing

¦ 1 in. between the gutter and an adjacent wall

¦ 2 in. between siding and roofing, decks, patios, driveways, steps and walkways (using PVC trim boards is a good way to accomplish these clearances)

¦ 6 in. between the siding and the ground.

DONT SKIP THE KICK-OUT FLASHING

Kick-out flashing is essential for preventing water from running down a roof and behind the siding on an adjacent wall. Youfail your inspection if the inspector doesnsee it on your job. Ita pain to work around, but it helps if you donnail the flashing tight until you have your siding cut to size. Itmuch easier to get a proper fit for a plank if you can shift the flashing beneath it.