A roof is the structure that covers a building. It protects against the elements, such as rain and sun.

Roofing work requires individuals to assume awkward body positions for long periods of time, which can increase the risk of injury. NIOSH research aims to reduce this risk through education and training.

The roof of a building or other structure forms the uppermost part of its envelope and protects the interior from rain, snow, sunlight, and wind. There are many different types of roofing materials. Some are designed to be long-lived and durable, while others are more aesthetic or designed to serve other purposes, such as insulation or ventilation. The choice of material also depends on the climate, as some regions experience extreme weather conditions that require specialized roofs.

Shingles are one of the most common roofing materials and come in a wide variety of shapes, sizes, and colors. They are usually constructed from a base mat of wood fiber, cellulose, paper, or other material saturated with asphalt and coated with ceramic granules that add to their durability and water resistance. They are typically attached to the roof deck with a layer of felt or other underlayment.

Some homeowners prefer the look of shake or slate roofs. These are more expensive than shingles, but they offer unique and attractive styles that can complement any home style. These roofs are not as durable, however, and must be inspected frequently for signs of damage or deterioration.

In addition to the type of roof, there are also several different types of valleys that can be used on a roof. For example, closed valleys have shingles that extend from one side of the roof to the other, while open valleys have flashing that extends past the shingle layer.

Roofing is an extremely labor-intensive job, and it is one of the leading causes of work-related musculoskeletal injuries in construction. Workers spend most of their time kneeling, stooping, crawling, and crouching on slanted surfaces, which can alter trunk biomechanics and increase the risk of low-back injury.

Materials

There are a wide variety of roofing materials available to protect the top of a building. The choices are based on native climate, cost, endurance, and aesthetics. Some of the most popular roofing materials include asphalt shingles, wood shakes, and slate. There are also several types of metal roofs. Other choices are stone, concrete, and solar panels. The most important factor in deciding which type of roofing materials to use is the local weather conditions.

A roofing system is designed to protect a building from rain, snow, direct sunlight, and extreme temperatures. The material chosen for this purpose will determine the durability, insulation, and overall strength of a roof. In addition to the roof material itself, the choice of construction methods will impact a building’s appearance and structural integrity.

Historically, the most common roofing materials were thatched straw, sticks, mud, and wood. Throughout the centuries, these simple and basic materials have been replaced by more sophisticated and durable options. Today’s modern roofing systems are generally made of a mixture of different base ingredients with added additives such as sand, clay, or rubber. The most commonly used roofing material in the United States is asphalt shingles.

Many homeowners are choosing roofing materials that are more environmentally friendly. This includes reusing old or damaged shingles to create a more sustainable and decorative roofing material. Some of these new roofing products are even helping to cut down on a building’s energy costs by absorbing or reflecting the sun’s rays.

There are also new roofing products that offer more insulation capability than older roofing materials. For example, mineral-surfaced leak barriers can help prevent damaging leaks in areas of the roof like eaves and valleys.

Roofing is a huge investment, and it’s vital to choose the right material for your home. A professional roofing contractor will help you decide which type of material is best for your home and climate. In addition, a roofing contractor will install the proper amount of insulation to keep your house cooler in the summer and warmer in the winter.

Installation

Roofing is dangerous work, and even with the proper gear, it takes a pretty skilled and fit person to do it. That’s why, if you’re not comfortable on your roof, hiring a professional is a good idea.

A contractor will use a full-sized pry bar or drill to loosen the screws that hold each panel in place. They’ll then pull the panels off and set them aside on the ground.

The next step is to run the underlayment over the ice and water barrier and drip edge, fastening it with cap nails every six inches along the edges and spreading it out more towards the middle. This process will continue until the underlayment is just below the roof’s ridge.

Felt underlayment can also maintain or increase the fire rating of your roof. In fact, some building codes require it. Check with your local building department to see what the requirements are in your area. Felt is available in different grades, from standard to flame-retardant. A contractor will choose the grade that meets your needs. Some underlayment is infused with copper to provide extra protection against the elements. The contractor will also waterproof the valleys, the areas where your roof slopes and forms a “V” shape.

Maintenance

Roofs are susceptible to damage from severe weather, debris accumulation, and age. Left unchecked, this can result in leaks and expensive repairs. A facility owner can minimize these costs by having a routine maintenance procedure in place and following it.

A typical roof maintenance procedure should include an initial survey to determine the general condition of the roofing system. This should be done on a regular basis, especially after extreme weather events. This early problem detection can save thousands of dollars in repair costs.

The initial housekeeping survey should include a visual examination of the entire roof surface and all drains, scuppers, and gutters for obstructions. Debris accumulation restricts drainage, accelerates membrane deterioration, and poses a puncture threat. It also creates localized ponding water that can prematurely damage the roofing material.

In addition to debris, the roof should be checked for deterioration of the surface and penetrations. Cracking, openings, and crazing of sealant should be corrected immediately to prevent leaking. This may require the replacement of the caulking.

Personnel should periodically be sent to perform housekeeping surveys on the roof. These should be done monthly on most roof areas. In some cases, this frequency may need to be increased at certain times of the year in geographic locations that experience seasonal weather changes. It is important that these personnel have the skills and training to perform these activities safely. In some facilities, the roof maintenance responsibilities can be assigned to mechanics responsible for the daily building preventive maintenance duties. Exceptional or extensive corrective maintenance and repair work should generally be contracted to roofing professionals.