RoofViews

Your Home

Is a Slate Roof Right for Your Home? Everything You Need to Know

By Dawn Killough

October 09, 2023

Slate roof against blue sky, Gray tile roof of construction house with blue sky and cloud of the sun

If you're looking to replace your roof, you've probably discovered that, along with colors, you have a few materials to choose from.

One roofing material that's been growing in popularity is slate. While it's been around for centuries, renewed interest has made it a top choice, alongside asphalt shingles and metal roofing.

Since your roof is one of the most important investments you'll make in your home, you want to choose the right one. With this in mind, here's everything you need to know to decide whether a slate roof is right for your home.

What Is a Slate Roof?

Slate is a metamorphic rock derived from clay or volcanic ash. It's mined in Vermont, New York, Pennsylvania, Virginia, and internationally in Italy. Thanks to its physical makeup, it can be split into layers or sheets that are then cut into tiles, which are used to cover surfaces like roofs or floors.

Slate comes in a palette of several natural colors and can be cut into a variety of sizes and shapes, making it a versatile roofing material. It's also water, fire, mold, temperature, insect, and weather-resistant. Because of its durability and low maintenance requirements, it's a favorite when it comes to long-lasting, durable roofs.

Are Slate Roofs Expensive to Install?

One of the downsides of slate tiles is that they're much more expensive than traditional asphalt shingles. They can also involve some additional installation costs.

If you're looking to transition from an asphalt roof to slate, you must make sure your home's structure can support the tiles' weight. Most homes aren't designed to carry slate's heavy load. You may need to add support or redesign your home's structural components, depending on how it's currently built.

And, as with any roof, additional factors can affect the installation costs, including:

  • The cost of roofing accessories, like flashing and venting
  • Accessibility
  • Size and complexity of the roof's design
  • The number of penetrations
  • Replacement of roof decking
  • Dumpster fees
  • Labor costs

All of these costs can quickly add up.

How Do You Maintain a Slate Roof?

The first step in maintaining any roof is an annual roof inspection. Note that slate is a brittle rock, so walking on it may crack or break the tiles. Inspections should be completed from the ground or on a ladder. Look for missing, broken, or cracked tiles. If tiles have chipped corners, you don't have to repair or replace them.

Any damaged tiles should be repaired or replaced by a professional roofer as soon as possible to prevent roof leaks. Water can seep through tile cracks, damage your roof deck, and potentially infiltrate your home's interior.

You can clean the roof using a soft brush and household soap and water. After scrubbing the tiles to remove moss and dirt, rinse them with a spray hose. Don't use a pressure washer to clean your roof as it can damage it.

When Should You Replace a Slate Roof?

Cracked slate tiles can be repaired, which can save you money on upkeep in the long run. However, if your roof is reaching the end of its lifespan, it may be time to replace it entirely. Here are some features to look for that may signify it's time to replace your roof:

  • Missing tiles
  • Tile color changes due to moisture
  • Broken tiles
  • Moss growth
  • Roof leaks

If you notice any of the above, call a professional roofer* to inspect your roof to determine if it can be repaired or needs replacement. Keep in mind that because slate is a natural material, it can be hard to find slate that matches the exact color of your existing roof. This may mean you'll need to replace your roof to maintain a consistent color.

Pros and Cons of a Slate Roof

Before deciding if this roofing material is right for your home, weigh the pros and cons.

Pros

  • Slate is a durable material. You can expect it to last a long time with regular maintenance and in a mild climate.
  • It's versatile and comes in a variety of colors, shapes, and sizes, so it will complement any decor or building style.
  • Slate is a sustainable resource. It can be recycled and has a long useful life, so it doesn't have to be replaced as often.

Cons

  • Slate is heavy. It weighs 8 to 10 pounds per square foot. Your home must be designed to carry that weight.
  • It's expensive. Slate costs more than asphalt shingles, and it may come with the additional cost of adding structural support to carry its weight.
  • Since slate is brittle, it can't withstand the weight of someone walking on it. Storm debris can also break the tiles.
  • As slate is a natural product, there's no warranty on it. You can receive a warranty on the roof installation, but any material defects won't be covered.

Slate Alternatives

Slate can be the right choice for some homeowners, but maybe you simply like the look of a slate roof and would love to achieve this look without the expense. In that case, consider asphalt shingles designed to mimic the look of slate tile, like GAF Slateline® Shingles. These shingles have shadow lines and tapered cuts that look three-dimensional while giving you the flexibility and lower cost of an asphalt shingle. And with the available warranty options, you can get affordable peace of mind.

Hoping to get the look of slate without the added costs and structural supports? Reach out to a GAF-certified contractor* to discuss Slateline® shingles for your home.


*Contractors enrolled in GAF certification programs are not employees or agents of GAF, and GAF does not control or otherwise supervise these independent businesses. Contractors may receive benefits, such as loyalty rewards points and discounts on marketing tools from GAF for participating in the program and offering GAF enhanced warranties, which require the use of a minimum amount of GAF products. Your dealings with a Contractor, and any services they provide to you, are subject to the GAF Contractor Terms of Use.

About the Author

Dawn Killough is a freelance writer in the construction, finance, and accounting fields. She is the author of an ebook about green building and writes for construction tech and green building websites. She lives in Salem, Oregon with her husband and four cats.

Related Articles

A couple looks at their home from the ground.
Your Home

How to Conduct a Roof Inspection from the Ground

As a homeowner, it's always a good idea to stay on top of routine maintenance that will help protect your biggest investment—and that includes a regular roof inspection. Catching leaks or damage early can help preserve your roof's longevity and prevent major issues.But getting up on a ladder to walk around on your roof can be dangerous. It's safer to visually inspect your roof from the ground. Read on to learn how to conduct a routine roof check, so you'll know when it's time to bring in a professional.Walk around the Entire PropertyTo see all the angles of your roof, you'll first need to walk around your home, looking up and down. Check for any fallen shingles or debris on the ground or any missing spots on the roof where shingles may have broken off.Using binoculars, look for moss, piles of leaves, algae, or other debris on the roof. If left unaddressed, this debris can damage the structure by trapping moisture, eventually causing it to seep into the sheathing beneath your shingles. After some time, this can develop into serious water damage and leaks.Look for Damaged ShinglesExcessive heat and moisture in your attic, typically caused by inadequate ventilation, may compromise the roof system's performance or even cause shingles to become misshapen or damaged. Loose, curled, cracked, or buckled shingles can leave room for water to seep in and damage your roof's underlayment.If you see shingles that don't look right or are missing altogether, consult a roofing professional. They can help you understand if it's a simple fix or indicative of something larger, meaning it could be time to replace the roof.Check Your Gutters, Fascia, and SoffitNext, look for obvious damage, such as holes, dents, mold, or cracks. Gutters clogged with branches, leaves, or dirt can prevent water from draining off the roof. Also, asphalt shingles contain small, gravel-like granules, and if you see this material has ended up in your gutters, it can mean the shingles are nearing the end of their lifespan. Inspect the downspout to be sure it's clear of debris, too.While you can remove leaves or sticks yourself, hire a gutter cleaning service for a larger blockage. If you need to climb a ladder to reach any part of your gutters, it's best to leave that to an insured service.Peek at the Flashings from the BalconyIf you have a balcony or other way to safely view your roof from above, get a closer look at the flashings. These are the metal components that redirect water from your roof, located around your chimney, vent pipes, and dormers.Flashings are often the most vulnerable areas around your roof and the first to show wear and tear. If they're dented, rusty, or otherwise damaged—or if the caulk is brittle or cracked—water can get into your roof's interior structure and lead to rot.Examine the Attic or CrawlspaceAfter your exterior inspection, head inside. Some hidden roof damage or water infiltration can be seen from your attic. Using a flashlight, look for signs of rotting wood joists, sunlight coming through the joints, water damage on the floor, or any vulnerable spots around vents, skylights, or the chimney. Also check your rafters, insulation, and any other wooden structures for signs of mold, moisture, and rot.Scan Your Home's InteriorSome early signs your roof might be leaking are obvious from inside the house. Look for damp spots near the fireplace, water stains on the pipes that vent your furnace or water heater, dark patches, or peeling paint on your ceilings.When to Go with a ProPerform a visual roof inspection twice a year—in the spring or early summer and again in the fall. Conducting regular inspections helps you get to know your roof and spot any issues immediately.If your roof looks like it's in good shape after your inspection, you probably don't need to call in a licensed roofing contractor. However, if you've seen any worrisome signs of damage or leaks, it's best to book a professional inspection before the issues worsen. A GAF-certified roofing contractor* can make any necessary repairs, so your roof continues to protect your most valuable asset.*Contractors enrolled in GAF certification programs are not employees or agents of GAF, and GAF does not control or otherwise supervise these independent businesses. Contractors may receive benefits, such as loyalty rewards points and discounts on marketing tools from GAF for participating in the program and offering GAF enhanced warranties, which require the use of a minimum amount of GAF products. Your dealings with a Contractor, and any services they provide to you, are subject to the GAF Contractor Terms of Use.

By Authors Wendy Helfenbaum

March 22, 2024

Timberline HD Reflector Series Birchwood House
Your Home

Best Roofing Materials and Colors for Energy Efficiency

Want to save money on your heating and cooling bills and keep your home feeling pleasant year-round, regardless of the weather outside? Opting for an energy-efficient roof might be the way to go.You can replace your existing roof with a new system that uses energy-efficient materials and colors. For instance, while a roof's color may seem like an aesthetic choice, it can play a part in keeping a house cooler in the summer by reflecting sunlight. Meanwhile, the best roofing materials for energy efficiency can help with thermal emittance and keep a house warmer in the winter.Here's a comprehensive overview of energy-efficient roofs, why color and material matter, and why you might consider updating your home's roof.Benefits of Energy-Efficient RoofsAside from offering protection from the outside elements, reducing your home's environmental impact, and enhancing its curb appeal, energy-efficient roofs can offer several benefits. With energy-efficient roofing materials, homeowners may notice cost savings through a reduction in energy consumption, and more interior comfort during particularly hot or cold weather conditions. The lifetime of a roof may even be extended, depending on manufacturer warranties. All of these factors can positively impact the resale value of your home when it's time to sell.Additionally, local laws may require your home to meet certain energy standards, which an energy-efficient roof can help with. For example, due to Title 24, California homes must comply with specific cool roof requirements. GAF shingles like Timberline HDZ® RS Shingles and Timberline® CS Shingles have been rated by the Cool Roof Rating Council (CRRC) for use in Title 24 projects. At GAF, a primary focus is building sustainable products that not only adhere to changing building standards, but also help create a more sustainable future.Most Energy-Efficient Roofing MaterialsGenerally, the most energy-efficient roofing materials are metal, tile, and asphalt. Here's how each of these materials differ.MetalMetal roofs are known for their longevity. Metal is also considered one of the best roofing materials for reflecting sunlight, which results in improved energy efficiency. Its strong insulation properties help keep the interior at a comfortable temperature while keeping out hot (or cold) exterior air. Lastly, metal roofs are environmentally friendly, as most of the material is recyclable.TileCommonly made from clay and slate, tile roofs are another energy-efficient option. Tile roofs are often seen in the Southwest, where daily temperatures can reach triple digits and the sun beats down most of the day. This roofing material sometimes comes preheated to help reduce heat absorption in sunny weather and high-temperature areas. You can also add coatings to the roof to further improve its reflectivity once it's installed.AsphaltWhile asphalt shingles are a popular choice across homes in the United States, they aren't known to have a lot of solar-reflecting ability. That said, many new energy-efficient asphalt shingles are equipped with solar-reflecting granules.For example, GAF Timberline® CS Shingles can help keep your attic cool and allow you to use your home's air conditioning system less. And GAF Timberline HDZ® RS Shingles, which are rated by the Cool Roof Rating Council, come in several light and dark finishes, so you can choose your color scheme. These shingles offer excellent performance and can withstand strong wind speeds, while giving you the same look as traditional asphalt shingles.Best Roof Colors to Reflect HeatLight roof colors tend to reflect more sunlight and heat than darker colors. Popular light colors used for energy-efficient homes are white, light gray, and light brown.White is the most effective roof color to reflect heat. According to the US Department of Energy, a white roof stays coolest because it can reflect anywhere from 60% to 90% of sunlight. Meanwhile, other products typically reflect 30% to 60% of sunlight. Darker colors tend to absorb more heat, with black roofs absorbing the most heat followed by brown and dark gray.Shingles That Reflect Heat Regardless of ColorThough darker colors tend to absorb more heat, you may want a darker roof to match your home's aesthetics. For example, if you want your home's siding to stand out, a dark-colored roof is more favorable than a light one.Today, you don't have to decide between color and energy efficiency: modern shingles, like GAF cool roof shingles, can still reflect heat despite their dark shade. For instance, GAF Timberline HDZ® RS+ Shingles are offered in charcoal, hickory, aged chestnut, and other rich colors while still maintaining their high energy efficiency. You can choose the color that best fits your home's design without having to sacrifice your roof's energy efficiency.When Color May Not Matter as MuchKeep in mind your local weather and your property's features. If your home doesn't get as much sun or is covered in shade by nearby trees, the color of your roof may not matter as much when it comes to solar reflectance.Other Ways to Improve Roof Energy EfficiencyApart from color and roofing material, you can take other steps to improve your roof's energy efficiency.InsulationAttic insulation protects your roof during any season. In the summer, it reduces the transfer of heat coming in from outside. While your roof material is the first line of protection, you can think of insulation as your second line of defense.Insulation also protects your home against humidity and can prevent pests from getting inside your home. During the winter months, attic insulation can also prevent ice dams that can lead to expensive damage.VentilationIf your roof doesn't have proper ventilation, heat will always make its way inside. Proper ventilation allows the warm air inside to constantly shift out through the vents and be replaced with cooler air. Apart from regulating temperatures, it reduces condensation, which can result in mold, and keeps your insulation in good condition. Adding roof and attic vents while ensuring insulation isn't covering any airflow is the best way to ensure good ventilation.Updating Your Roof with Modern MaterialsFor more help navigating the variety of energy-efficient roofing materials available, speak to a local contractor. These professionals can tell you what's most popular in your area and help you understand the advantages you could enjoy after upgrading to a more energy-efficient roof.

By Authors Mark Soto

March 22, 2024

The GAF TimberSteel™ premium metal roofing system on a house
Your Home

3 Disadvantages of a Standing Seam Metal Roof

When you're choosing the right roofing material for your home, you might rule out metal. Metal roofs are often expensive and noisy, and they can look wavy or distorted (known as oil canning). However, GAF has an alternative that allows you to get the durability and aesthetic appeal of a metal roof—without the high cost and finish concerns.What Is a Standing Seam Metal Roof?A standing seam metal roof is a series of mechanically attached metal panels. The attachment points, called standing seams, create a thin ridge along the outside of each panel. These seams allow the metal to expand and contract as the temperature changes without sacrificing the roof's ability to protect your home from moisture. The panels are attached to the roof structure under each seam. The fasteners don't show externally, giving the roof a consistent look.Disadvantages of a Standing Seam Metal RoofStanding seam metal roofs are known for their smooth aesthetic and durability. But they can have three significant downsides.1. PriceBetween the cost of metal and the need for professionally trained installers, standing seam roofs can cost two to three times as much as a standard asphalt shingle roof. The material cost depends on the metal's thickness, the requested finish, and the roof's size. Installation can also cost more because it takes specialized training to install the panels correctly. If they're not, they can experience leaks and metal expansion.2. NoiseWhen it rains on a metal roof, it's noisy. Attaching the roof panels to solid wood decking and adding rigid insulation can help reduce the noise level, but you can't completely get rid of it. You might like hearing the pitter-patter of raindrops on your roof during a storm. But if you don't want this extra noise in your home, you may want to avoid a metal roof.3. Oil CanningOil canning is a finish issue that occurs when the metal panels are fastened too closely together. The panels have room to expand lengthwise but not sideways. The finish begins to look like it's bubbling and continues to get wavier over time. Note that oil canning is an aesthetic issue caused by improper installation, not a material defect. The roof will continue to offer protection but will appear warped.An Alternative to Standing Seam Metal RoofsThe GAF TimberSteel™ premium metal roofing system provides an alternative to standing seam metal roofs. Here are some features to keep in mind.1. Lower costThe TimberSteel™ system can be easier on the budget and easier to install than a traditional standing seam metal roof. While installation costs will vary by location, GAF's system offers more efficient installation than traditional standing seam panels, giving you the opportunity to save additional time and money.2. BeautyInstead of sacrificing looks for durability, the GAF TimberSteel™ system is made with an embossed vertical grain, giving the appearance of traditional roof shingles, with the strength of steel. It is specifically designed to help avoid common issues, like oil canning, that traditional metal roofs present. The TimberSteel™ system is also available in a variety of colors to suit your home and taste.3. Durable finishAs the first metal shingle from GAF, the TimberSteel™ Premium Metal Roofing System is constructed out of GALVALUME® steel and coated with a combination of aluminum and zinc, which help to protect against corrosion. The GAF TimberSteel™ system also passes UL's toughest impact-resistance test — UL 2218 Class 4.In addition, metal roof systems are completely recyclable when reaching the end of its useful life, making them a great choice for the environment.While GAF's new metal roofing system is currently only available in select areas, you can learn more and sign up to receive information about the TimberSteel™ system, including updates on availability in your area, by visiting gaf.com/metal.

By Authors Dawn Killough

March 22, 2024

Don't miss another GAF RoofViews post!

Subscribe now