How Much Do Slate Roof Repairs Cost? [2025 Data]

Slate Roof Repair Cost Factors

Many factors can impact the cost of slate roof repairs, including the size of your roof, the materials, labor, prep work, and location. Here's a breakdown of each of these factors to help you tally up your expenses. 

Type of Repair

Several different types of slate roof repairs can impact the cost of your project. Below are the most common roofing repairs.

Individual Slate Tile Replacement 

If you only need to replace individual slate tiles, you’ll spend somewhere between $50 and $200 per tile. The total cost depends on where you live and the scope of the work. Some pros include fastening reparation and sealing services while replacing tiles, which can increase the cost.

Flashing and Fastening Replacement

Roof flashing and fastening replacement costs anywhere from $600 to $20,000 based on the roof size and materials. Copper has one of the highest price tags, galvanized steel falls somewhere in the middle, while aluminum costs the least on average. Most slate roofs need copper flashings and fastenings, as they have a long life span. However, synthetic slate can use galvanized steel.

Underlayment

Your roof's underlayment provides a necessary protective layer in case water finds its way underneath the slate. However, underlayment can develop holes and damage, which limits its ability to protect your home. Underlayment repair can be spot or area patching or replacement and costs between $800 and $16,000 on average. The size of the area and labor costs are the most prominent pricing factors.

Size of Damaged Area

The average cost to repair a slate roof is between $5 and $15 per square foot. If you only need a few tiles repaired, your expenses could be minor, but repairing an entire slate roof can really rack up in price. 

Most roofing materials come in roofing squares, with one square equalling 100 square feet. Replacing an entire slate roof could cost upward of $15,000, but most repair projects are much smaller than this. Prices range from less than $500 for individual tile replacements to more than $7,500 for more extensive work.

Let’s look at how much your repairs could cost based on the different sizes.

Natural vs. Synthetic Slate

Of the two types of slate roofing materials available, natural stone slate and synthetic slate, the cost of repairs averages $2 less per square foot for synthetic varieties.

Natural slate roofing is authentic stone and can suffer impact damage more readily than synthetic varieties. While the material can last over 100 years, it's heavy and costs an average of $10 per square foot to repair when necessary.

On the other hand, synthetic slate has a shorter lifespan of up to 80 years but is more resilient and easier to maintain. Repairs are also less costly than natural slate, averaging $9 per square foot. 

Labor

Labor for slate roofs ranges from $4 to $17 per square foot, depending on the conditions, slope, and complexity. Due to its weight and the skill level required to repair or replace it safely, slate costs $2 to $15 more per square foot to repair than other roofing materials. 

Repairing underlying structural problems may require the expertise of a local structural engineer in addition to a roofing contractor. Structural engineers cost between $350 and $775 on average to hire.

Prep

Prep work can add to the cost of your project. For example, if you need to remove existing tiles, you'll need to set aside an additional $1 to $5 per square foot. If you just need to replace the mechanisms that hold the roof or gutter together, you won't necessarily need to account for the removal of your roof. 

Location

If your local roofing company needs to repair a slate roof in inclement weather, you may pay more for repairing a slate roof. This means homes in extremely hot, cold, or wet climates could face higher costs. 

Meanwhile, accessibility also plays a major role in labor costs. A roof located under trees may require tree trimming services, whereas a uniquely shaped roof could require more time, effort, and money to repair.

Repairing vs. Replacing a Slate Roof

The cost to install a new slate roof on your home averages between $10 and $30 per square foot, which is significantly more per foot than most repair tasks. However, several circumstances can affect whether you choose to repair or replace your roof.

If your home's slate roof is nearing or older than its expected lifespan of around 100 years, you should consider replacing it. Potential signs that replacement is the best option include persistent leaking, sagging, or higher energy bills.

Additionally, in cases where more than 30% of the roof is damaged, such as in a storm damage situation, replacement can be the better choice.

Some repair work tasks, such as flashing or underlayment fixes, can be quite costly. If your expected repair costs exceed 50% of the cost of replacing the roof, getting a new roof option can be a good choice, especially if it’s needed frequent repairs.

While slate roof repairs are more cost-effective than a full roof replacement, the advantages of installing a new roof include the promise of likely never having to do the job again while enjoying less frequent repairs.

DIY Slate Roof Repair vs. Hiring a Pro

Since labor for slate roof repairs costs anywhere from $4 to $17 per square foot, you might be tempted to save on robust projects by repairing your slate roof yourself. We don’t recommend DIYing slate roof repairs or replacements because the stone is heavy and challenging to work with, requiring the skills of a trained professional to handle it correctly. If you install slate tiles incorrectly, you could cause the tiles to crack and lead to costly water damage.

For this reason, it’s best to hire a professional slate roof installer near you. When vetting local pros, always double-check their qualifications to ensure they have experience working with slate tiles, as general roofing skills won’t cut it for this type of material. 

5 Ways You Can Save Money When Repairing a Slate Roof

There’s no way around it—repairing a slate roof can be a costly endeavor. But the following tips can potentially save on the cost of repairing a slate roof.

• Don’t settle for one price. Instead, compare at least three contractors to choose the best roofing pro for the job.

• Research each company to make sure that they do reputable work to avoid future issues and premature repairs.

• Hire a pro during the off-season, like spring or winter, to potentially find lower offerings.

• See if your contractor can salvage old materials and reuse them.

• DIY prep work that helps clear the way for workers, like removing obstacles and trimming branches and shrubs.

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

Want to help us improve our cost data? Send us a recent project quote to costquotes@angi.com. Quotes and personal information will not be shared publicly.