How to Put Cedar Shingles Over Present House Siding

Inspect the existing siding to locate any loose material or other flaws. Install cedar shingles over wood, brick, stucco or synthetic materials, but not over vinyl or aluminum siding, which are not strong enough to support nailing. Drive in or replace any loose nails or fasteners and repair any damaged siding material so there is a solid surface.

Install new molding strips around windows and doors; in some cases, you may have to extend door and window casings to conform to the added thickness of cedar shingles. Fasten new molding to existing casings with a hammer and galvanized nails long enough to penetrate into the original wood. Adapt molding to the thickness of the shingles. Staple a moisture membrane, such as felt or roofing paper, over a wood or stucco wall.

Put furring strips on masonry or stucco walls, long enough to run from the bottom of the wall to the top. Fasten 1-by-3-inch or 1-by-4-inch furring vertically, 16 inches apart, using appropriate nails. Secure furring to masonry with concrete nails driven into mortar joints; use galvanized nails on stucco long enough to penetrate the facing and into the wood sheathing underneath. Drive all nails flush with the surface of the furring.

Add 1-by-2-inch horizontal nailing strips across the furring on masonry or stucco. Put a first strip along the bottom of the wall. Use a level to make sure it is level. Space these according to the dimensions of the shingles; each shingle should fit over two nailing strips, one at the top and one in the center. Fasten nailing strips to furring with galvanized nails.

Place cedar shingles directly over wood or synthetic siding such as cement fiber. Use thin strips of low grade lumber or plywood to even out the surface with beveled or other decorative siding, if necessary, to provide a smoother nailing surface. Rip these on a table saw to a thickness to match the bevel; nail strips with small nails under the bottom beveled edge to level the wall surface.

Nail on a double layer of shingles at the bottom of the wall. Align the bottom of the shingles with the edge of the horizontal nailing strip or siding board and fasten them with galvanized shingle nails at the top and in the center. Nail shingles to the beveled edges on wood siding. Put the second layer of the first course with the bottoms slightly above the first shingles. Overlap shingles so the second course covers the seams of the first course. Leave a 1/8-inch gap between shingle sides.

Add shingles up the wall. Nail each shingle to the nailing strip or bevel at the top and in the center of the shingle. Overlap shingles so an upper course covers the nails on the shingles below. Stagger vertical joints, so each shingle on an upper course is over half of two shingles below. Work to the top of the wall. Finish the shingling with solid board trim on corners and under the roof eave. Add new trim around doors and windows.