Homeowner maintenance includes cleaning the leaves and debris from the roof’s valleys and gutters. Debris in the valleys can cause water to dam and wick under the shingles and cause damage to the interior of the roof. Clogged rain gutters can cause water to flow back under the shingles on the eaves and cause damage. Whatever the roofing material may be including composition shingle, wood shake, tile or metal. The best way to preserve your roof is to stay off it. Also, seasonal changes in the weather are usually the most destructive forces.

There are two types of roofs, flat and pitched (sloped). Most commercial, industrial, and apartment buildings have flat or slightly sloping roofs. Most houses have pitched roofs. Some roofers work on both types; others specialize.

Most residential roofs are covered with shingles. To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing felt lengthwise over the entire roof. Second, starting from the bottom edge, they staple or nail overlapping rows of shingles to the roof. Workers measure and cut the felt and shingles to fit intersecting roof surfaces and to fit around vent pipes and chimneys. Wherever two roof surfaces intersect, or shingles reach a vent pipe or chimney, roofers cement or nail flashing-strips of metal or shingle over the joints to make them watertight. Finally, roofers cover exposed nail heads with roofing cement or caulking to prevent water leakage. Roofers who use tile, metal shingles, or shakes follow a similar process. Some roofer’s also waterproof and damp proof masonry and concrete walls and floors. To prepare surfaces for waterproofing, they hammer and chisel away rough spots, or remove them with a rubbing brick, before applying a coat of liquid waterproofing compound. They also may paint or spray surfaces with a waterproofing material, or attach waterproofing membrane to surfaces. When damp proofing, they usually spray a bitumen-based coating on interior or exterior surfaces.

Asphalt is the most commonly used roofing material. Asphalt products include shingles, roll-roofing, built-up roofing, and modified bitumen membranes. Asphalt shingles are typically the most common and economical choice for residential roofing. They come in a variety of colors, shapes, and textures. There are four different types: strip, laminated, interlocking, and large individual shingles. Laminated shingles consist of more than one layer of tabs to provide extra thickness. Interlocking shingles are used to provide greater wind resistance. And large individual shingles generally come in rectangular and hexagonal shapes. Roll-roofing products are generally used in residential applications, mostly for underlayment’s and flashings. Built-up roofing is the most popular choice of roofing used on commercial, industrial and institutional buildings.

Most metal roofing products consist of steel or aluminum, although some consist of copper and other metals. Steel is invariably galvanized by the application of zinc or zinc/aluminum coating, which greatly reduces the rate of corrosion.  Metal roofs with solid sheathing control noise from rain, hail, and bad weather just as well as any other roofing material. Metal roofing costs more than asphalt, but it typically lasts 2 to 3 times longer than asphalt or wood shingles.

Wood shakes offer a natural look with a lot of character. Because of variations like color, width, thickness, or cut of the wood, no two shake roofs will ever be the same. Wood offers some energy benefits, too. It helps to insulate the attic, and it allows the house to breathe, circulating air through the small openings under the felt rows on which wooden shingles are laid.

Concrete tiles are made of extruded concrete that is colored. Traditional roofing tiles are made from clay. Concrete and clay tile roofing systems are durable, aesthetically appealing, and low in maintenance. They also provide energy savings and are environmentally friendly. Although material and installation costs are higher for concrete and clay tile roofs, when evaluated on a price versus performance basis, they may outperform other roofing materials.

Single-ply membranes are flexible sheets of compounded synthetic materials that are manufactured in a factory. There are three types of membranes: thermosets, thermoplastics, and modified bitumen. These materials provide strength, flexibility, and long-lasting durability. The advantages of pre-fabricated sheets are the consistency of the product quality, the versatility in their attachment methods, and therefore, their broader applicability.

If you aren't sure whether your house is at risk from natural disasters, check with your local fire marshall, building official, city engineer, or planning and zoning administrator. They can tell you whether you are in a hazard area. Also, they usually can tell you how to protect yourself and your house and property from damage. Protection can involve a variety of changes to your house and property, changes that can vary in complexity and cost. You may be able to make some types of changes yourself. But complicated or large-scale changes and those that affect the structure of your house or its electrical wiring and plumbing should be carried out only by a professional contractor licensed to work in your state, county, or city. One example is fire protection, by replacing flammable roofing materials with fire-resistant materials. This is something that most homeowners would probably hire a contractor to do.

The age of your roof is usually the major factor in determining when to replace it. Most roofs last many years if properly installed and often can be repaired rather than replaced. An isolated leak usually can be repaired. The average life expectancy of a typical residential roof is 15 to 20 years. Water damage to a home’s interior or overhangs is commonly caused by leaks from a single weathered portion of the roof, poorly installed flashing, or from around chimneys and skylights. These problems do not necessarily mean you need a new roof.

One of the best ways to select a roofing contractor is to ask friends or relatives for recommendations. You may also contact a professional roofers association for referrals. Professional associations have stringent guidelines for their members to follow. The roofers association in your area will provide you with a list of available contractors. Follow these guidelines when selecting a contractor...

Make sure everything is in writing. The contract is one of the best ways to prevent problems before you begin. The contract protects you and the contractor by including everything you have both agreed upon. Get all promises in writing and spell out exactly what the contractor will and will not do.

Make sure the contractor carries worker’s compensation insurance and general liability insurance in case of accidents on the job. Ask to have copies of these policies for your job file. You should protect yourself from mechanics lien against your home in the event the contractor does no pay subcontractors or material suppliers. You may be able to protect yourself by having a release of lien clause in your contract. A release of lien clause requires the contractor, subcontractors and suppliers to furnish a certificate of waiver of lien. If you are financing your project, the bank or lending institution may require that the contractor, subcontractors and suppliers verify that they have been paid, before releasing funds for subsequent phases of the project. A leaky roof can damage ceilings, walls, and furnishings. To protect buildings and their contents from water damage, roofers repair and install roofs made of tar or asphalt and gravel; rubber or thermoplastic; metal; or shingles made of asphalt, slate, fiberglass, wood, tile, or other material. Roofers also may waterproof foundation walls and floors. Keep these points in mind if you plan to have your existing roofing materials replaced: