Cement lap siding, also called fiber cement or hardboard, has been around for about a hundred years. Back in the day, it was made with asbestos, but modern cement siding is Portland cement, sand, water, and cellulose fiber. Besides being versatile and durable, it can take paint well, and the paint lasts a bit longer, though exterior painting can take longer and be more work. This siding can also be purchased with the color baked in.
This type of siding can be manufactured to look like wood, cedar-type shingles, stucco, or smooth large panels, and is earth-friendly. While mining and manufacturing the base takes energy (Portland cement is made of limestone and clay), and the cellulose sources can be doubtful, it is resistant to rot, fire, and insects. The durability is what makes it environmentally sound.
The pricing of this siding is more than vinyl or aluminum, but about equal with that of wood. It is more durable and less toxic than vinyl and needs less maintenance than wood. Cement lap siding can be more work to install, therefore costlier than other siding installation, and should be installed by professionals. The good news is more and more contractors are experienced with it, making it easier to find someone to install.
Many of the same techniques and tools for wood can be used with cement lap siding, but the cutting of it can be dusty. The dust contains silica, something that can cause respiratory problems, and a dust mask should be worn. Otherwise, it can be cut by scoring and snapping. Dust collecting saws with carbide-tipped blades, dust free pneumatic and electric shears can also be used.
The installation is much the same as wood lap. The top of the board is nailed in; the next board above it overlaps enough to cover the fasteners holding the first board on. Corners, windows, and doors can be trimmed with 1″ thick cement lap trim. All gaps should be caulked carefully.
Because of the labor and difficulty involved, installing this or any other siding is not a do-it-yourself job. Cement fiber siding is considerably less expensive and much less work than a total refurbish of wood siding. This is a good green alternative to other sidings.