Though vinyl remains the cheapest and most used siding, fiber cement keeps making strides in the market. Known for its higher-end appearance, durability, and green qualities, it is expected to lead siding in growth through 2008, reaching almost 14 million squares, says a forecast by the Freedonia Group, a market research company.

Responding to fiber cement's growing popularity, James Hardie now offers Artisan, a thicker profile that imitates cedar shake. CertainTeed uses recycled fly ash instead of sand to enhance the siding's green qualities, and Nichiha added more colors to its Sierra line of imitation shake product. Even though fiber cement presents more costs to distributors, its surging popularity encourages more of them to keep it in stock.

"It's gaining market share, even in the down market," says Ted Herick, an outside sales representative for United Products, a distributor of roofing and siding products. "People want to buy it, so we stock it."

Fiber cement's durability fuels its growth, experts say. The siding resists termites and UV rays and doesn't rot. It has a high fire rating, and its weight makes it less prone to thermal-induced movement. Many manufacturers warranty the board for at least 50 years.

In addition, experts say, fiber cement has an attractive appearance.

"It's just more authentic-looking and has a firmer feel than other fiber products," says John Witt, COO of Lansing Building Products, a distributor in Richmond, Va. This, he says, makes it appealing to remodelers. And, now that fiber cement is gaining exposure, manufacturers are producing more styles and profiles.

MaxiTile offers various textures, including one that imitates cedar shake. Nichiha launched a fiber cement board that is pressed, not layered, so its graining looks deeper, says Darrin Haugan, executive vice president of sales and marketing for Nichiha. Fiber cement leader James Hardie has introduced Artisan, which is twice as thick as regular fiber cement and imitates cedar.

Accessories are also coming to market. "When [fiber cement products] were first introduced, they were horizontal clapboards or vertical planks," says Donn Thompson, residential technology manager for the Portland Cement Association. "Now... there are trim pieces, corner boards, soffit material, and shingle pieces."

Fiber cement once had to be painted by a third party, but manufacturers now offer prefinished versions, such as James Hardie's ColorPlus, CertainTeed's ColorMax and MaxiTile's MaxiColor. Nichiha recently added more shake colors.

"Customers want it prefinished," says Brent Fox, vice president of merchandising and purchasing for ABC Supply, a roofing and siding distributor. "They are used to getting their vinyl in a multitude of colors right out of the carton."

Fiber cement also feeds the exploding green trend. "There are no petroleum products involved," says Tony Ellis, director of business development for MaxiTile. "It's basically sand, Portland cement, and fiber."

Going a step further, CertainTeed redesigned its fiber cement siding to use recycled fly ash instead of sand. "We're diverting that material from going to a landfill," says Lisa Santerian, CertainTeed's marketing manager for fiber cement.

Even with its benefits and appeal, fiber cement still presents more costs to dealers and distributors. It weighs more, so transportation requires larger trucks, trucks with forklifts, and more consideration during its fastening. Fiber cement is more delicate than vinyl, so shipping and handling calls for more precautions. It also needs cutting equipment.

Fiber cement "can capture a higher-end market," Fox says. "It just, point blank in the story, costs more."

–Victoria Markovitz