The Functions of a Roof
What does a roof do? It’s there to protect your home from the elements, including:
Is your roof working at its best? Whether you’re building a new home or repairing an existing roof, you need to look at the way you’re building and the materials you use to make sure that each part of your roof and drainage system works with the others to protect your home.
How Are Roofs Made?
You’ve probably heard the story. Once upon a time, there was a wolf, three little pigs, and their three houses – one of straw, one of wood, and one of brick. At the end, the house made of brick was the only one still standing. Today’s roofs are made out of all sorts of materials, and they’re made to endure the rigors of all kinds of huffing, puffing, and blowing. Through wind, rain, snow, and ice, they stand strong. Here’s how a roof is made to last:
- Roofs are made from layers. Beginning with the roof deck and ending with the shingles, your roof layers act as a unified system to protect your home from the elements.
- The layers overlap to protect what’s underneath. The shingles on your home sit partially on top of the next shingle down.
- Overlapping shingles allow the roof to shed water without sending the water through cracks and into the roof.
- When shingles overlap, this prevents them from being moved upward by the wind when there is a storm.
The Layers of a Roof
A roof is like a thick sandwich, and each layer plays its own role in the function of the whole. What are the layers of a roof, and how do they work together?
|Framing||Your roof begins with the frame. These are the trusses that run across your attic and support the weight of all of the other parts of your roof.|
|Insulation||Insulation keeps your home from changing temperature rapidly in the winter and summer. It’s not part of your roof, but it lies directly under it. If your roof doesn’t work properly, your insulation often becomes damaged by water.|
|Roof Deck||The roof deck is the beginning of your roof. It goes on top of the frame. It is the substrate that your roof layers sit on.|
|Starter Shingles||Starter shingles are a layer of shingles along the side of your roof lines. They go under the upper layers and make it easier for roofers to complete the roof because they don’t need to reach over the sides. They also protect the edges of the roof from the weather.|
|Underlayment||The underlayment sits beneath the final layer of shingles. This material provides a flat surface where roofers can install the shingles. It also protects the roof deck in case water moves under the shingles.|
|Roof Shingles||Shingles are one of the most important elements of your roof. They’re the layer that people see, so they add to the beauty of your home. They’re also the first layer of protection on your roof, so you need to add shingles that will function well in your climate.|
|Ridge Cap||On top of the slope of your roof is the ridge cap. This cap is like a hat for your shingles. It provides an extra seal at the apex or ridge line of the roof. This helps prevent damage from rain and snow, and it also makes the roof look more complete.|
What Kind of Shingles Are Best?
The shingles are the top layer of your roof. Shingles come in different materials, such as clay, wood, and plastic. If you decide to get a new roof, you need to make sure that your shingles suit the aesthetics of your home. However, even more importantly, your shingles must excel at doing the many jobs of a roof. They should keep your safe from heat, cold, wind, rain, snow, and ice. The materials you choose will determine how well your roof functions in your climate. Here’s how each type of shingle succeeds or fails in different climates and conditions:
|Type of Shingle||Pros||Cons|
|Wood||Attractive for heritage homes. Pressure-treated shakes with fire retardant may meet fire standards.||Shakes mold and rot easily, get insect damage, and are often not appropriate for climates with high fire danger.|
|Asphalt||Easy to install and repair. Class A fire protection.||Can blow off in high winds. Material scars when hot.|
|Clay, Slate, and Concrete||Won’t rot, burn, or get insect damage.||Can be fragile and prone to breakage from debris.|
|Metal||Durable, fire retardant||Very expensive|
Are Sloped or Flat Roofs Better?
Your shingles rest on the structure of your roof, and that structure has a slope. When you’re buying a new house, renovating your home, or building a new house, you need to know how to choose the best roofing slope to ensure that your roof will function well. There are many different styles of roof, but these roofing styles are among the most common:
|Gable||This roof looks like an inverted “v” shape. Some gabled roofs are more complicated and have multiple gables.||These roofs shed water and snow easily. They are simple and cheap to build.||They need strong supports to stay strong in areas with high winds or hurricanes, or they can collapse or detach from the walls.|
|Hipped||This roof has slopes on four sides. The slopes come together at the top to form a ridge.||The four sides make this roof style more durable. They also shed snow easily.||There are more seams, so the roof can have more trouble with durability and leaks.|
|Flat or Low-Sloped Roofs||Roofs that look flat aren’t actually flat. They just have a very low slope.||These inexpensive roofs function well in climates that have little snow or rain. Roofs that are engineered for a large load can also become a rooftop garden or outdoor living space.||In a snowy or rainy climate, these roofs can fail is there is a high snow or water load on the roof.|
Your Roof Works With Other Systems to Protect Your Home
Your roof may be a superhero when it comes to protecting your home, but it doesn’t act alone. It works with other systems to provide thorough home protection. Three of these systems are particularly important to the integrity of your roof. They are:
|Ventilation||Ventilation is critical to making sure that your interior and your roof function as a team. You need to move air and moisture from your attic into the world outside, and vents in your roof do this. According to Building Science, “in a cold climate, the primary purpose of ventilation is to maintain a cold roof temperature to avoid ice dams created by melting snow and to vent any moisture that moves from the conditioned living space to the attic.” In a hot climate, the roof vents help the house release warm air to the surrounding environment, making it easier to cool the home.|
|Gutters||Your gutters help your roof shed rain, snow, and ice. Gutter systems are designed to move water from the roof into drainage systems that carry water into appropriate places in your yard. They protect the edge of your roof by providing a rot-proof place for moisture, and they protect your home’s foundation by preventing water from moving from the roof to the ground below. To enhance your drainage system, you can add gutter guards to prevent your gutters from getting clogged, and you can add heating systems to your gutters to help them effectively melt and remove snow and ice.|
|Downspouts||Downspouts and drains are at the end of your roof’s drainage systems. Like your gutters, downspouts move water from one place to another, depositing it into underground pipes or into the garden, where it moves away from the house or into a specially designed rain garden. To keep your downspouts functioning properly, you need to ensure that they are free of debris.|
Protecting Your Roof From Snow, Ice, Heat, and Moss
Your roof protects your home, but you need to protect your roof as well. A roofing system can’t work as it’s designed to work if you don’t protect it from some of the biggest threats to roofing, including snow, ice, heat, and moss.
Snow and ice can damage your roof even when you think it’s not there. As snow falls on your roof, it warms, melts, and turns to ice at the edge of the roof. This ice creates ice dams in your gutters, causing water to back up onto the shingles. This leads to leaks in your roof. You can protect your roof by installing gutter heating systems to prevent the ice from forming before it begins. Install insulation in your attic to prevent the roof from getting too warm and melting the snow in the first place.
Heat damage can cause your roof to get old before its time. This can also be due to attic heat. Add insulation and proper attic vents to make sure that your attic does not get too warm and damage the roofing above.
Moss and mold occur when your roof is constantly moist. You can prevent this by inspecting your roof, gutters, and downspouts regularly to make sure that they are draining properly. Some types of shingles such as wooden shakes are more prone to rot, insect damage, and other problems triggered by water.
Is It Time to Repair Your Roof?
Sometimes your roof doesn’t work as it was designed to do. This is generally due to a failure in one of your roof layers. It’s time to repair your roof if you notice:
- Visible damage from storms
- Cracked or unusually smooth areas due to ongoing wear
- Mold or mildew smells or visible mold or mildew inside the house
- Leaks in the ceiling
- Damaged gutters and shingles pushed up due to ice dams
- Pieces of shingle in your gutters or downspouts
- Damage around vents or other seams, such as ridges or skylights
Check your roof regularly to make sure that it’s working as it should, and you’ll have a home that’s secure from the weather.
At Harry Helmet, we’re here to help your roof function at its best. We not only install roofs, we also install the systems that support your roof. Are you trying to add or renovate your roof so that it’s both beautiful and functional? Learn more about roofing, Gutter Helmet, and Helmet Heat today.