The outside wall sheathing or covering on a frame structure consists of either wood siding or paneling, wood shingles, plywood, fiberboard, hardboard, and/or other types of materials. Masonry, veneers, metal or plastic siding, and other non-wood materials are additional choices. There are two general types of wooden board siding: drop siding and common siding. DROP SIDING (fig. 6-50) is joined edge to edge (rather than overlapping). COMMON SIDING consists of boards that overlap each other single-wise.

Boards not more than 4 ft long are called clapboard; boards in longer lengths but not more than 8 in. wide are called bevel siding. A number of drop board and common sidings can be used horizontally or vertically (fig. 6-51), and some

may be used in either manner if adequate nailing areas are provided. Figure 6-52 shows a method of vertical siding application.

Masonry veneers are used effectively with wood sidings in various exterior finishes to enhance the aesthetic appearance of the structure. Other non-wood materials, such as stucco or a cement plaster finish, are favored for an exterior cover because they require a minimum of maintenance. Plastic films on wood sidings or plywood are also used because little or no refinishing is necessary for the life of the building.