A roof is a key structural element that protects a home from weather damage. It also adds beauty to the property. Begin with the framework stage. This involves building the structure’s shape and incorporating elements to allow drainage. Then, the deck or sheathing is laid. This layer supports other layers, such as shingles. 
Choosing the right roof material is one of the most important decisions you’ll make when you’re building or replacing your home. You need a sturdy material that adds value to your property and will hold up well to years of wear and tear. You’ll also want to consider your budget, as some materials are more expensive than others.
Asphalt shingles are the most popular residential roofing material, offering a good combination of affordability and longevity. They are die-cut from heavy sheets of asphalt-impregnated felt and coated with mineral granules for a protective layer and decorative finish. They are available in a range of profiles to suit different styles of homes.
A metal roof is an alternative to traditional shingles and comes in galvanized aluminum, and copper varieties. The latter is the most durable, but also the most expensive. The ridges and valleys of a roof are often covered with sheet metal, which can be soldered or welded to the rest of the roof. Metal roofing is highly insulated and can add significantly to the energy efficiency of your home.
Wood shingles and shakes are attractive and long-lasting, but they’re not ideal for areas that experience frequent rain or where wildfires are a risk. They require regular maintenance to keep them in good condition, and they’re not as fire-resistant as other roofing materials.
Slate tiles are a luxurious choice for a roof, but they’re also very expensive and time-consuming to install. They are quarried in a variety of colors and have a surface that can range from rough to smooth.
Underlayment
While roof-covering materials are the primary defense against leaks, the underlayment provides a secondary layer of waterproofing. Its purpose is to keep moisture from penetrating the deck of your roof, whether in its liquid or vapor form. Underlayment is also a critical factor in determining the durability and longevity of your roofing system.
Many roofing professionals use felt underlayment for its affordable pricing and versatility. It is not fully waterproof, however, and must be covered with the primary roofing material immediately. It also tends to wrinkle and crack, and its volatile compounds disperse quickly in warmer climates.
In more recent times, synthetic underlayment has become the preferred option for most roof professionals. This underlayment has a base mat saturated with asphalt, and it is reinforced with fiberglass for added stability. This type of underlayment is much lighter than felt, and it can withstand harsh weather conditions. It is also a better choice for areas of the roof that are particularly susceptible to leakage, such as penetrations and low-slope sections.
Some forms of underlayment, such as rubberized asphalt, feature self-adhesive properties that eliminate the need for fasteners. This type of underlayment is usually rolled out like carpet, and it is easy to install. It is naturally compression-resistant and offers excellent acoustic properties.
Before laying the underlayment, it is important to remove or pound down protruding nails from previous shingles. Otherwise, the leaking water and air will penetrate through these holes, causing further damage to your home and roof. It is also recommended to install a metal drip edge at the roof’s perimeter, although this may not be required by local building codes (check with your building official). This gives the roof a finished look, prevents shingles from curling over the edges, and helps keep water from running directly down the fascia boards.
Shingles
Roofing shingles are both a functional element of the roof system and a key exterior design component. They come in a wide variety of colors, textures, and materials. Asphalt shingles are the most common, but wood, clay, and metal shingles can be used to add a distinctive look to your home.
When installing shingles, you must pay careful attention to the installation instructions provided by the shingle manufacturer. Problems may arise if too much exposure or offset is allowed between shingles in successive courses (rows of shingles). The shingle’s nailing pattern and placement also play a role. Insufficient or improper nailing will reduce the shingle’s wind resistance and can cause leaks in the roof.
Before starting, carefully measure the area of your roof in square feet to determine how many shingles you’ll need. This information is necessary to accurately purchase the roofing supplies you need and to apply the underlayment correctly. Shingles are usually sold in bundles that contain three shingle “squares,” which is sufficient to cover approximately 20 square feet of roof.
The first row of shingles — often called the starter strip — should overhang the drip edge by about a half-inch. This will help prevent water from seeping up under the shingles as it flows off the roof.
You should use a shingle nailer to attach each shingle, following the instructions provided by the manufacturer. In general, four nails are recommended per shingle.
If your roof has a valley, it should be flashed before the shingles are installed. Typically, the valley is finished first on one side and then the other. The shingle courses should overlap each other by at least 12” through the centerline of the valley.
Flashing
Flashing is one of the most important parts of roof installation because it prevents water leaks. It’s installed around openings in your roof, such as those made by vents, pipes, skylights, and decorative items. It also helps protect areas of your home from moisture damage, such as the interior walls near roof penetrations. If you notice discoloration on these walls, leaking around window frames, and an increase in exterior noise, you likely need to replace or repair your flashing.
There are a variety of flashing materials, including aluminum, copper, and galvanized steel. A roofing contractor will choose the material that’s best for your roof. Aluminum is cost-friendly and durable, but it can corrode in contact with certain types of house siding. Copper is more expensive but offers greater longevity and resists rust. Galvanized steel is less expensive but not as durable as other types of flashing.
When you install flashing, it’s important to follow proper steps to ensure that it’s done correctly. First, you’ll need to have all the necessary tools ready and lay down the underlayment and shingles before installing the flashing. You’ll also need to use a waterproof sealant on the seams of the flashing and around the opening in your roof where the flashing meets it.
If you’re working with a dormer window, the flashing will need to be bent to accommodate the slope of your roof. A dormer is a structural element that projects out from the side of your house and adds headroom inside. The flashing may be installed as a strip that wraps around the dormer or as individual pieces that are added in between each row of shingles on the slope of the roof.
Roof Windows
If you want to brighten up an area of your home that is low on natural light, roof windows (or rooflines) might be a good solution. These windows let in up to five times more light than a normal window and add plenty of warmth, too. However, they aren’t right for every roof or home and must adhere to very strict specifications and building regulations. The process of installing a roof window can also be more complex and costly than for a standard wall window.
It’s important to know the difference between a roof window and a skylight when researching your options. A skylight is a window set into your roof that doesn’t open, whereas a roof window has the option to open and may include ventilation features.
Both roof windows and skylights offer a great opportunity to add value to your property, especially if they are correctly located and in the correct size for your space. They’re also effective at bringing light into your home or commercial space and can help to keep the building warmer in winter and cooler in summer.
Depending on the model you choose, a roof window can be flat or sloped and is typically suitable for both flat or pitched roofs. Some models specifically state whether they can be used in particular situations and on certain roof types.
Choosing the right frame for your roof window is important as it has a significant impact on thermal performance. The frame is the primary barrier to heat transfer and must be well insulated to prevent condensation and loss of energy. A wide range of frames is available, from timber with external weatherproof cladding to aluminum and steel.
