Most homeowners don’t pay much attention to their roof until rain or melt-ing snow starts to leak through
itthen it demands immediate action. But if you periodically inspect your roof, you can correct minor problems before they become serious enough to cause damage.
Understanding the structure of your roof (see below) is the first step toward diagnosing possible problems.
On the facing page, you’ll find direc-tions for inspecting your roof from the inside and outside. If your inspection in-dicates that repairs are necessary refer to pages 31-38.
CAUTION; Tile and slate roofs are extremely slippery, and the materials can break easily; metal and plastic
roofs also tend to be slippery. If your house has one of these out-of-the-ordinary roofs, it’s best to leave inspec-ion and repairs to a professional roof-ng contractor.
Understanding Roofing Structure
Inspecting for Damage
Locating a Roof Leak
Understanding Roofing Structure
A roof protects a house from damage by the elements, especially water. Roofs are designed to shed water; the parts comprising a roof combine to di-rect water off the roof and away from the house.
Anatomy of a roof
A typical roof (see illustration at right) begins with a framework of rafters which supports a roof deck (sometimes called a subroof) consisting of sheath-ing and underlayment. The roof deck, in turn, provides a nailing base for the roof surface material.
The roof deck. Though the type of roof deck used can vary depending on the roof surface material, most decks have both sheathing and underlayment.
Sheathing, the material that pro-vides the nailing base for the roof sur-face material, ranges from solid ply-
wood to fiberboard to open sheathing (used with wood shakes).
Sandwiched between the sheath-ing and the surface material is the underlayment, usually roofing felt. A
heavy, fibrous black paper saturated with asphalt, roofing felt is thick enough to resist water penetration from outside, yet thin enough to allow moisture from inside the attic to escape.
The roof surface. The material on the roof must be able to withstand wind, rain, snow, hail, and sun. A wide variety of roof surface materials is available the different types are discussed at right and on pages 31-33.
The surface of the roof is often bro-ken by angles and protrusions, all of which require weatherproofing-
sually provided by the flashing. Made from malleable metal or plastic, flash-ing appears as the drip edge along the eaves and rakes of a roof, the collars around ventilation and plumbing pipes, the valleys between two roof planes, and the “steps” along a chimney or dormer. Less obvious flashing also pro-tects other breaks in the roof, such as around some solar panels and sky-lights. At the roof edges, metal, wood,
or vinyl gutters catch water runoff and channel it to the ground via the down-spouts, which direct water away from the house and into the soil.
Types of roofing materials
Roofing varies widely in size, shape, and material. Traditional sloping roofs are usually covered with overlapping layers of asphalt shingles, wood shin-gles or shakes, or tile, though you can find such roofs covered with slate, alu-minum, or galvanized steel. Flat or low-sloping roofs are most often surfaced with alternating layers of roofing felt and asphalt, with a layer of gravel on top. These are known as built-up, or tar-and-gravel, roofs. Some flat roofs are covered with insulating Polyurethane foam.
Inspecting for Damage
It’s a good idea to inspect and repair your roof in autumn, before the hard weather hits. Then examine the roof again in spring to assess whatever damage may have occurred during the winter. If you discover problems, make the necessary repairs, following the in-structions on pages 31-38.
Inspecting from inside. Begin an in-spection in the attic, using a strong flashlight, a thin screwdriver, a knife, and a piece of chalk to examine the ridge beam, rafters, and sheathing. Look for water stains, dark-colored areas of wet wood, moisture, and soft spots that may indicate dry rot. Mark the wet spots with chalk so you can find them easily later on.
If it’s necessary to remove fiber-glass insulation batts to examine the sheathing, be sure to wear loose cloth-ing, gloves, goggles, and a respirator for protection.
Next, turn off any lights. If you see any holes above you, drive nails or poke wire through them so they’ll be visible from the roof’s surface. (In a wood shingle roof, small shafts of light coming in at an angle indicate cracks that may swell shut when the shingles are wet.)
Inspecting from outside. When you examine the roof from outdoors, evalu-ate the condition of the roof structure, surface material, flashings, eaves, and gutters.
To check the roof structure, stand back from the house and look at the lines of the ridge and rafters. The ridge line should be perfectly horizontal, and the line of the rafters, which you can assess by looking along the plane of each roof section, should be straight. If either sags, call in a professional contractoryou may have a structural problem.
Next, inspect the roof’s surface. Before climbing up on your roof, be sure to read the safety tips on page 30. If you’re at all nervous about going up on the roof, make the inspection from a ladder, using a pair of binoculars. Don’t walk on the roof any more than is abso-lutely necessary; you can easily cause more damage.
Inspect the flashings for rust spots and broken seals along the edges. If you have metal gutters and down-
spouts, look for rust spots and holes. Then examine the roof surface for signs of wear, loose or broken nails, or curled, broken, or missing shingles.
Use a knife and screwdriver to test the boards along the eaves and rakes. Scrape out any damage caused by dry rot, treat with a wood preservative, and fill the holes with wood putty If the dam-age is extensive, replace the boards and finish them to match the existing areas.
Locating a Roof Leak
Roof leaks usually appear during storms, when you can’t make per-manent repairs. But you can take some
steps to temporarily divert or halt the flow of water, as shown below.
Generally leaks begin at a roof’s most vulnerable spots-t flashings, where shingles are damaged or miss-
ing, in valleys, or at eaves. Often, the water shows up far from its point of ori-gin after working its way through layers of roofing materials and down rafters to collect in a puddle on the attic or bed-room floor.
During a storm, trace the course of water from where it’s dripping through the ceiling to where it’s coming through the roof. Drive a nail or poke wire through the hole so you can find the hole later when you get up on the roof.
Once the roof is dry enough, check it thoroughly looking for weak spots that indicate a source for the leak.
Keep in mind that the point where a nail or wire is poking through may be below the actual source. Make permanent repairs as described on pages 31-33.
Temporary Repairs of a Leaky Roof
