Many of today’s standard exterior finishes have been protecting walls from the weather for centuries. Other exterior finishes, such as plywood, vinyl, and hardboard, have been developed in recent years. Regardless of their history, each is capable of protecting the building for as long as the finish material lasts, but only when applied properly. If possible, the best way to protect the exterior finish and the building itself from the weather is with proper window installation, adequate overhangs, and seamless gutters. But even the wind-driven rain will occasionally get the building wet. Therefore, it is important to detail the exterior wall finishes carefully at all but the most protected locations.
Keeping Water Off Your Walls Starts With Siding Installation
Introducing effective moisture barriers under your home’s siding can potentially prolong the life of walls beyond the life of the siding alone. Siding and roofing provide the first line of defense against Maryland weather. One of its other functions is to keep sunlight from causing deterioration of the moisture barrier, ultimately protecting the building walls. Where the moisture barrier stops–at the edges and openings through the wall–special attention should be paid to the detailing of exterior wall finishes.
Vertical Wood Siding Installation and Replacement
Vertical wood siding falls into two main groups: The first group, such as the tongue-and-groove and channel patterns, has its side edges rabbeted or grooved. This type of siding lies flat on the wall, one-board thick. The second main group, including board and batten, has squared edges. It uses a second layer to cover the edges of the first layer. The denser patterns in the second group may require careful coordination with castings and trim. Both groups need 5/8-inch (minimum) plywood sheathing or horizontal nailing strips to strengthen the wall. Siding is sealed where end joints occur and joined with a scarf joint or a miter joint sloped to the exterior.
Horizontal Siding Replacement and Installation
Horizontal wood siding is common in both modern and historic buildings. Horizontal boards cast a horizontal shadow line unique to this type of siding. Cedar, redwood, and pine are most commonly used for horizontal siding. Some profiles are also made from composite hardboard or cement board. This material is much less expensive than siding milled from lumber and is almost indistinguishable from it when painted. Siding joints may be tongue and groove, rabbeted, or lapped. Horizontal siding boards are typically applied over the moisture barrier and sheathing. It should generally be back-primed before being installed. After that, boards are face nailed with a single nail near each board’s bottom but above the board below. This allows for necessary movement. Siding is joined end-to-end with miter or scarf joints. Many Catonsville homeowners paint or stain their siding after this step. Clear lumber siding can also be treated with a semitransparent stain.
Vinyl Siding Installation and Replacement
Vinyl sidings were developed as an alternative to the maintenance-heavy requirements of wood sidings. Most aluminum-siding manufacturers have now moved to vinyl. There are several shapes of vinyl siding available. Most resemble horizontal wood bevel patterns, but there are some vertical patterns as well. Vinyl itself is structurally weak, so most vinyl sidings need to be installed on top of solid sheathing. Corrosion-resistant nails and proper nailing practices are essential in order to allow for natural expansion and contractions over time. Because vinyl trim pieces are narrow, many architects choose to use vinyl siding alongside wood trim.