Slate roof tile basics: pros, cons and costs.

What is a slate roof?

Natural slate roofing is typically made from metamorphic rocks and has been used in homes and buildings for centuries. Slate is durable and tough — it can withstand many of the outside elements. It’s hard yet brittle (it may crack if a heavy object is dropped onto it) and smooth to the touch. Slate is also resistant to insects, fungus, mold and fires. It also has low water absorption. 

This roofing material is also very attractive. Its mineral composition determines what color your slate roofing will come in. Typically, you’ll find slate that’s naturally gray, black, green, purple or red. When it comes time to design your slate roof, you can opt for a patterned, multicolored and/or textured look. A slate roof can go with any architectural style. 

Before being made into roofing tiles, slate is sawn, cut and split before it’s finished and sometimes “flamed” to create a slightly textured finish, according to the Natural Slate Association. In addition to being used as roof tiles, natural slate is also used in flooring, countertops, backsplashes and more. 

Slate roof pros and cons.

What are the benefits of installing slate roof tiles?

• Curb appeal and appearance. Slate has an effortless charm to it. That’s why many companies are appealing to cost-conscious homeowners by selling roofing materials that mimic the appearance of slate. Not only is it more original, striking and distinctive, but also natural slate gives you the freedom to be creative when it comes to the colors. Some colors occur naturally, while others can only be achieved with paint. 
• Durability and resistance to potential damage. Natural slate can hold up pretty well against insects, fires, rain, snow, wind and hail. It’s resistant to mold and fungus. It also has low water absorption, which helps prevent rotting.
• Long lifespan. Installing slate roof tiles is something you’ll likely do just once in your life. It can last 60-150 years. Whether you plan to live in your home forever, pass it down to future generations or sell it to someone else, slate roofing is a worthwhile investment.

What are the disadvantages of a slate roof?

• Cost. This is an upscale roofing material, so the price will be higher than other roofing options (such as asphalt shingles). The high cost of slate roofing is due to its prestige and performance. Slate tiles often require little maintenance — but repairs can be expensive too.
• Installation. Slate roofing requires trained, experienced and highly skilled roofing contractors and professionals - not just any handyman can install slate roofing. You can’t just watch a video online and become a slate roof expert. You’ll need to thoroughly research the professionals you’re considering to ensure they have successfully installed slate roofs before. 
• Handling heaviness. Slate tiles don’t do well under serious tonnage, and they may crack if a heavy object (like a tree) falls on top of your roof. Also, the slate itself is pretty heavy. You may need to have someone inspect your home to ensure it can support a slate roof.

How much does a slate roof cost?

A slate roof will cost approximately $800-$1,500 per square, according to the Metal Roofing Alliance. However, several factors can drive that price up or down. A professional needs to take your roof’s condition, layout, slope and size to determine the labor cost. 

When it comes to material costs, certain colors, finishes and styles may also have different costs. Of course, the bigger your roof, the more materials you’ll need — and the more expensive this project will become.

How long does a slate roof last?

Slate has the highest life expectancy of any roofing material, with some lasting 60-150 years. In fact, there are old buildings, homes, churches and castles around the world that still have slate roofs.

As with any part of your home, how well you maintain your roof will determine its lifespan. The climate, environment and weather also contribute to a slate roof’s longevity. Although it’s resistant to hail and wind, extreme weather can cause dents, cracks and other damage.

Slate roof shingles installed on steeper slopes tend to last longer than those installed on flat roofs. Your roofers should also use nails with a lifespan that equals the slate’s lifespan. 

Natural slate vs. synthetic slate roofing.

Synthetic (or faux) slate shingles are typically made from rubber and plastic but can look like real slate. For some homeowners, synthetic slate roofing may be a more attractive option; but, there are a few things to keep in mind before you go down this route.

Some roofing companies claim that synthetic slate is much cheaper than real slate — and that may be true when it comes to installation. However, synthetic slate may last only 10 years, which means you’ll need to spend more money to replace it. The Natural Stone Institute also argues that synthetic slate is not as environmentally friendly and easy to maintain as you may believe. 

Before you choose synthetic slate, do your research. You may want to consider installing architectural (or laminated) shingles that look like slate. That’s fine (architectural shingles are a common choice for many homes), but make sure you choose a reputable manufacturer and hire a roofer to install your shingles.

Related: Buying guide: How to choose the best roof shingles.

Slate roof maintenance considerations.

The secret to getting the most bang for your buck after you install your slate roof? Stay on top of maintenance.

Remember these tips:

• Routinely check for leaks, cracks and broken slate tiles. When inspecting your roof, it’s important to be thorough and check inside out for leaks. Cracks will call for a closer inspection, but that’s probably best left to someone with some roofing experience and gear. Check on your roof more than once a year, and definitely, after your home endures severe weather (hail storms, hurricanes and high winds).
• Clean your roof and gutters a few times a year. Remove any foreign materials on or around the roof and clear the gutters of any obstructions. 
• Remove ice buildup. If ice accumulates on the roof when it’s cold, remove it unless you want your tiles to break. Remember to be gentle, and avoid cracking the ice through sudden movements. 
• Don’t step on those slate roof tiles. Find a way to inspect your roof from the ground up. 
• Avoid placing anything heavy on your roof as you conduct preventative maintenance. If you have a camera that zooms in far enough, use that to check out what’s going on up there. 
• Contact a professional for repairs ASAP. If you see any damaged shingles, you better call a roofing professional as soon as possible. 

Is a slate roof worth it?

A house constructed with high-quality materials has more value. Because slate roof tiles look great and last a long time, the high cost to install them may be a worthwhile investment for you and your family. Potential homebuyers will find the slate roof quite refreshing, considering there aren’t that many of them out there.

Just remember that while your tiles might last a century, you do need to factor in the cost of maintenance and repairs. Make sure you’re working with a skilled roofer and a reputable slate manufacturer. 

Hire roofers on Thumbtack.

If you want your roofing done right the first time (with no need for expensive do-overs), then you should hire a professional roofer who can handle the unique challenges and needs of slate roof tiles. A professional can do a clean job that leaves nothing to be desired. 

Slate roofs are tricky, so make sure your pro is experienced. You can find slate roofing contractors on Thumbtack, where you can also read their customer reviews. Look up the roofers’ licenses and credentials, and take a peek at their portfolios to view before-and-after photos of slate roof installations they’ve completed in the past. 

Once you’ve picked out a few roofers who seem fit for the job, ask them for consultations and price quotes. Compare several quotes until you feel like you’ve secured a fair price that fits within your budget. 

FAQs.

Is it OK to walk on a slate roof?

Under no circumstances should you walk on your slate roof, as you’d be causing damage to your roofing system and thus signing up for constant repairs.

Slate is strong enough for harsh weather, but it generally doesn’t do well under too much pressure caused by walking. Slate tiles are slippery, brittle and fragile. When professionals install them, they use a ladder or scaffolding. 

Why do slate roofs fail?

A few things may cause a slate roof to fail. For example, your slate roof may fail if you walk on the roof or if the installation was done by a roofer who doesn’t have a lot of experience with slate roof tiles. Heavy objects, trees and hail can cause dents and other damage. 

Remember that slate is heavy. So if your home isn’t structurally sound or strong enough to support its weight, it could be a disaster. 

Finally, if you don’t maintain your roof, you won’t be able to tell if something’s about to go wrong. If even one slate gets out of place, you need to know about it. The sooner you deal with these small challenges, the better chance you have of preventing your roof from failing.