Materials

Roofing tiles are made from a variety of different materials, including shale, shale and clay, cement, cement and asbestos, and metal. Both curved and flat types are available for installation on roofs. Curved tiles are manufactured in the mission and Spanish style designs; flat tiles in the shingle and interlocking designs.
Mission roofing tiles are laid in courses which overlap on alternating sides. The concave side, or cover, forms a course Cover Tile Used to Cap the Ridge of tiles which overlaps with the convex parallel courses on either side. The cover tile is nailed to a wood strip fastened to the roof sheathing; whereas the pan tile is nailed directly to the sheathing. The roof ridge is capped by a cover tile which is nailed to a wood strip fastened to the ridge.

Spanish roofing tiles have a flange or lip running the length of one side of the tile. The tiles are fastened to the roof with nails through the flange. The roof ridge is capped with a tile similar in design to the mission-style cover tile.

Shingle tiles are flat tiles that are nailed to the roof in much the same way that wood shingles or shakes are. The roof ridge is capped with a curved tile resembling a mission style cover tile, which is nailed and cemented in place.

These tiles are held in place by a lip or leg at one end which hooks over a 1 x 3 strip of wood nailed to the sheathing. Interlocking flat tiles have a bend or lip at each end which interlocks with the courses above and below it. The ridge tiles are also flat and are cemented together (and to the ridge) to form an angular cap.

Always examine the roof framing before laying a tile roof. This is a very heavy roofing material, and it requires strong framing to support it. It may be necessary to add bracing to carry the additional weight. The bracing should consist of 2 x 4’s cut to fit between the sheathing and the floor, and placed every five feet or so, on either side of the roof ridge.

Tile roofs are very slippery and you should be extremely careful when walking on this type of surface. Watch your footing, and use a safety rope and harness. Nonmetal tiles are also brittle, and you should take care to distribute your weight evenly when walking on them. Try to step on two tiles at a time rather than placing your weight on a single tile.

REPAIRING A TILE ROOF

A raked tile can be repaired with a number of different synthetic sealers. Ask your local building supply dealer for advice. If the tile is too damaged to repair, remove it and replace it with a new one. You may have to cut nails holding the broken tile to the roof. This can be done with a hacksaw blade or nail ripper inserted under the tile. Examine the surface of the roofing felt under the tile for rips or holes. These should be repaired with a patch and some roofing cement before inserting the new tile.

Cut a piece of copper or aluminum flashing to fit under the new tile. The flashing should be long enough and wide enough to lie under the adjoining tiles. It should also be about 1A inch longer than the length of the tile when installed. The extra 1A inch is bent up to hold the new tile in place. Nail the flashing in place and cover the nail heads with roofing cement.

Slate Roofing

Slate is a heavy, durable, nonporous rock material that formerly enjoyed considerable popularity as a roof covering. It is difficult to work with, not only from the standpoint of the material, but also because it is slippery to stand on and can crack under the weight of a man. The same precautions taken with tile roofing also apply here.

Because slate is a heavy roofing material, check the roof framing to be sure that it is capable of supporting the additional weight. The instructions for bracing a tile roof will also apply here. Begin work by covering the sheathing with overlapping layers of roofing felt. Let each layer overlap at least 2 to 3 inches and staple it to the sheathing.

Lay a starter course of slate along the edge of the roof, allowing the slate to extend past the roof edge approximately 1 inch. The slate in the starter course is laid lengthwise along the edge of the roof. Nail holes are punched in the slate with a center punch and hammer. Copper wire nails at least IV2 inches long are used to attach the slate to the sheathing.

Some roofers prefer to lay a strip of roofing felt over the starter course and staple it to the sheathing. This will serve as a cushion between the starter course and the first course of slate.

The first course of slate is laid over the starter course, but with the width of each slate paralleling the eave. The first course of slate should be started with a half piece so that the vertical joints are staggered for each course. Cut the first slate by scoring it deeply down the middle with a chisel and breaking off the unwanted half by tapping it with a hammer. On most roofs, the courses should overlap about 3 inches. A 2 inch overlap is permitted on steep roofs.

Do not nail the slate down too tightly or you may cause the slate to split. Drive the nail in so that it is flush with the slate. Coat the edge of the last course of slate along the ridge of the roof with roofing cement.

REPAIRING A SLATE ROOF

A cracked slate can be repaired by filling the crack with asphalt roofing cement, putty or a suitable synthetic sealer. These materials can also be used to reattach a loose slate.

A slate too damaged to repair should be removed and replaced with a new one. If nails are still holding a portion of the slate to the roof, cut them with a hacksaw blade or nail ripper inserted between the roof and the slate. Cut a new piece of slate to fill the space. Slate can be trimmed to size by scoring deeply along a line with a chisel and breaking off the excess by tapping lightly with a hammer. Hold the piece of slate on a smooth surface, and punch new nail holes with a center punch. Do not allow the new holes to line up with the old ones on the roof. Fill in the old holes with roofing cement.

Nail a strip of metal flashing to the roof. It should be long enough so that the upper portion extends under the slate above the replacement piece, and its lower portion is about VA inch longer than the new piece of slate. Nail the new piece of slate down, and bend the lower extended edge of flashing up to hold it in place.

 

Metal Roofing

Different types of metals are used as roof coverings. These roofing materials are available in thin, lightweight sheets of galvanized iron, aluminum, copper, roofing tin (Terne), zinc and monel metal. Corrugated or crimped sheet metal roofing is the easiest type to apply.

The manufacturer of a metal roofing material will generally provide detailed instructions about installing it. Read these instructions carefully and be sure you understand them before you begin roofing. If you have any questions, the manufacturer’s local representative should be able to answer them.

Always use nails of the same material as the metal roofing. Different metals sometimes react to one another and corrode. The manufacturer of the metal roofing will specify the type of nail to use in the instructions. If instructions are not available, ask for advice at your local building-supply house.

Metal roofing can be applied over an existing roof, but only after the old roofing has been properly prepared. It is essential that all loose shingles be nailed down; damaged ones replaced; and any leaks located and repaired. Added protection can be obtained by covering the old roof with roofing felt before laying the metal roofing.

REPAIRING METAL ROOFS

Holes and broken seams are the most common source of leaks on metal roofs. Other sources of leaks include loose nails, faulty joints, and improper installation of the metal sheets. If the metal sheets have not been installed properly, they should be removed and re-laid. Loose nails should be replaced. A faulty joint can sometimes be soldered.

Small holes can be sealed by filling them with roofing compound, a drop of solder, putty, or a suitable synthetic sealer. Clean the area around the hole with steel wool before filling it. A large hole will require a patch of the same material.

The area to be covered with the patch should be rubbed with steel wool or emery cloth until the metal is bright. A metal brush is recommended for this purpose if the roofing metal has been painted. Apply an acid flux to the area around the hole and to the bottom of the patch. Tin each surface with a thin coat of solder. Soldering a patch to a metal roof is difficult, and should be done by an experienced worker.

A painted metal roof occasionally requires repainting. Although there are paints that can be applied over rust, it is a good idea to remove any rust and loose paint with a stiff wire brush before repainting.

Consult your local paint dealer before repainting. Different paints are required for the different types of metal used in roofing. A primer coat may be necessary. Never paint copper roofs. It is possible to paint colored aluminum roofs, but a special exterior paint is required for the job. Ask your local dealer about this.