Classic slate roofing is made from natural slate rock, a fine-grained, metamorphic rock composed of clay or volcanic ash. It has been used for centuries as a durable and attractive roofing option for residential and commercial buildings, which can be proven by multiple historic buildings that have come down to our time.
A slate roof costs a pretty penny upfront, yet its longevity and natural aesthetics justify the investment. Plus, budget-conscious homeowners can pay heed to cheaper slate roofing alternatives made of synthetic components. Hybrid and synthetic slate roofs offer the aesthetics and durability of natural material while requiring less maintenance and excluding weight issues.
Read on to discover how the cost of slate roof tiles varies by their type, style, and hardness and what factors should be considered budgeting a roofing installation project. In addition, you will find estimates for different roof sizes and can make up your mind about the best slate options for your home.
The national average cost of a slate roof
The cost of slate roofing may go as high as $45.000 for tiling a steep 2,000-square-foot roof with hard slate or as low as $6.700 for tiling a one-story home with synthetic slate. The national average cost fluctuates from $8.800 to $26.000, including material and labor, while most homeowners pay $17.200 per project.
Average price range
$8.800 - $26.000
Slate roof tiles cost by material type
Slate roofing is a general notion that covers organic and synthetic roofing materials that mimic the authentic appearance of high-end natural slate tiles and cedar shakes. As the type of slate makes a big difference to the project’s total cost, we highlight this point separately. See below to find the average cost range for each slate subtype.
If you're in the market for an aesthetically appealing, long-lasting, and durable roofing material that can serve you for almost a century without showing visible signs of deterioration, then traditional slate roofing made from a real rock is your best bet. Nevertheless, this premium material is expensive and requires skilled installation.
Natural slate tiles come in two variations that determine their sturdiness and durability - hard and soft.
Hard slate has a dense composition that makes it long-lasting and resistant to extreme weather conditions. This roofing option has a less porous structure than its soft counterpart, making it less susceptible to water absorption and staining. Hard slate is not vulnerable to fading and requires minimal upkeep, yet it is heavier than soft slate, which means additional spending on roof reinforcement. The average hard slate tile roof costs $20 - $30 per square foot, including material and labor.
Soft slate is cheaper than its hard alternative, yet it is more brittle, which reduces its lifespan to 50 years. In addition, due to its porous structure, soft slate is vulnerable to moisture absorption and staining. Plus, it may fade and crack over time. That is why you should be ready to clean and seal it every 10 - 12 months for a better look and durability. Nevertheless, soft slate roofing is lighter than hard and can be installed without additional structural support. The soft slate roofing tiles cost $10 - $25 per square foot, including material and labor.
Slate roof hardness
Average cost per sq. ft.
$20 - $30
$10 - $25
Synthetic slate roofing presents a combination of synthetic and recyclable materials, such as rubber, plastic, and composite, that are blended to mimic the appearance of a natural slate. This lightweight and eco-friendly material gains momentum in today's roofing market as its affordability and low maintenance perfectly blend with its classic appearance. However, it may not have the same lifespan as a natural slate.
Here are the national average installation costs of synthetic roofing materials that are used to mimic natural slate:
Hybrid slate combines natural and synthetic or composite components. It is lighter and cheaper than natural slate while maintaining its aesthetics and durability. With a natural slate layer on the outer side, a hybrid slate shows decent resistance to fading and cracking. It may serve for more than 70 years, costing from $9 to $16 per square foot, which makes it a cost-effective roofing solution.
The average slate roofing tiles cost by roof size
The roof's size and structure determine the roofing project's scope of work, including supplies and labor. As a rule of thumb, pitched roofs sized more than 2,500 square feet are costlier to tile with slate than low-sloped ones of 1,000 - 1,500 square feet. Please, keep that in mind calculating the budget needed to install a new slate roof.
Slate roof replacement cost by roof size
Roof square footage
The average cost to install
$11.800 - $34.800
$15.800 - $48.800
$21.000 - $61.000
$24.000 - $70.000
$29.000 - $88.000
Labor cost to replace a slate roof
When estimating your slate roofing project, consider both material and installation costs, as labor accounts for as much as 60% of the total cost. For instance, an average $20.000 project is split 60% to 40%, where slate and other materials are estimated at $8.000 and roofer services $12.000.
Installing natural slate tiles is challenging and requires a more skilled and meticulous approach than other roofing materials, mainly because of their weight and fragility. Some roofing systems also need additional reinforcement to get slate tiles mounted on them. That is why you should be ready to spend from $130 to $230 per square to install natural slate on your roof. The cost to install synthetic and hybrid slate ranges from $80 to $100 and from $100 to $110 per square, respectively.
Please note that factors like the size and complexity of the roof, location, and the experience of the roofing contractor may greatly add to the overall installation cost. Therefore, getting multiple quotes from qualified roofing contractors in the area is essential to ensure you receive a fair and accurate estimate for your specific project.
Factors affecting the slate roof replacement cost
When budgeting a slate roofing project, you should also consider factors that contribute to the project's scope. See below to discover some key factors that may add to the average slate roof replacement cost:
Roof pitch. While larger roofs do require more materials and labor, they usually have a lower cost per square foot. However, labor costs tend to rise for roofs with steep inclines, particularly those with pitches steeper than 6:12.
Roof design. Roofs that have complex designs, including numerous corners, valleys, skylights, and penetrations, demand more labor and materials to complete the installation.
Installation method. Roofs with steep slopes often require installing a batten, which might appear 15% - 25% more expensive than attaching tiles directly to the roof deck.
Slate quality. The American Society for Testing and Materials (ASTM) classifies slate into three grades: S1, S2, or S3. S1 slate is the most expensive, has the longest lifespan, and is the most commonly used slate for homes in the United States.
Slate thickness. Thicker slate tiles are heavier and more challenging to install, which leads to increased labor costs.
Slate color. Unfading slate typically costs up to 25% more than weathering and semi-weathering slate colors.
Additional services to consider calculating a new slate roof cost
A few related roofing services may contribute to the overall cost of a slate roofing project. Pros do not recommend cutting corners on these services as they ensure the longevity and functionality of a new roof. See the table below to better understand their nature and average costs.
Roofing replacement usually requires getting permits to ensure the project complies with local building codes and regulations. The permit process and fee vary from state to state but is typically estimated at $200 to $500.
Roofers often perform a thorough roof inspection before installing new tiles on it. They assess the overall roof condition to identify potential issues that need to be addressed prior to the installation. This approach ensures the new roof is installed correctly, provides long-lasting protection, and complies with local building codes. Depending on the location, roof inspection costs $120 - $320 on average.
Old roof removal
Slate is a heavy material that is not installed over the existing roofing. That is why the removal and disposal of the old roofing should be considered in the overall project cost estimation. The complexity and labor involved in this process can vary depending on the roof's size and material. If you need to replace old slate roofing, you can expect to spend up to $5 per square foot.
Before installing a new slate roof or partially replacing an existing one, any damaged or deteriorated slate tiles may need to be repaired or replaced. This process typically involves assessing the current state of the slate tiles, identifying the ones that need attention, and carefully removing and replacing them with new tiles that match the existing roof's appearance. Any attic or flashing damages should also be eliminated before installing new material. The cost of repairs depends on the complexity and damage extent as well as the size and condition of the roof. But generally, homeowners spend around $300 - $1.500 to tackle medium roof damages.
Installing underlayment is a crucial step in the roofing process, as it provides a barrier to protect the roof deck from moisture and improves the roofing system's overall performance. Depending on the underlayment material and roof size, you should expect to pay from $0.10 to $0.90 per square foot, excluding labor.
Due to the weight of slate tiles, your roof structure might require reinforcement to support the added load. This may involve adding framing or bracing to the existing roof system. You can expect roof reinforcement to greatly add to the project's overall cost. The average price of this labor-intensive job goes from $650 to $2.500, depending on the roof size and structure.
Damaged or rotted roof rafters may need to be replaced before installing a new slate roof. Replacing rafters involves removing the affected sections and installing new ones, which can impact the overall project cost through increased labor and materials. As a rule, roofing contractors charge from $5 to $14 per square foot for this service. The cost mainly hinges on the size and complexity of the roof, the type of material used for rafters, roof accessibility, and local labor costs.
Soffits & fascia installation
Replacing soffits and fascia costs a pretty penny (around $3.500), yet this step is essential for your roof's structural integrity and moisture protection. Soffits help ventilate the attic space and protect the eaves from moisture and pests, while fascia creates a smooth and finished appearance at the roof's edge.
Roof vent installation
Upgrading or installing new roof vents can add to the overall cost of the roofing project by up to $700, as additional materials would be needed. Nevertheless, this add-on is worth the price as ventilation helps maintain a balanced airflow in the attic, reducing the risk of moisture problems and ensuring energy efficiency.
Investing in slate roofing can be worth it for several reasons. First, this high-end roofing with a classic appearance can enhance your home's curb appeal and increase its sale price. Second, natural slate is known to last for a century, making it a long-lasting investment.
How to prolong the service life of a slate roof?
If you want your natural slate roof to last the expected service life, you should follow proper maintenance and care practices. First, conduct periodic inspections of your roof. If you find any damaged or missing tiles, arrange for prompt repairs by a qualified roofing professional. Second, regularly clean and maintain your roof's gutter system and monitor the roof's ventilation. Third, avoid foot traffic on the roof without urgent need. And last but not least, trim any tree branches that overhang your roof to prevent them from falling and damaging the slate tiles.
How to skimp on slate roof installation?
You can save on slate roofing installation by selecting a synthetic or hybrid slate rather than the more expensive natural slate. Plus, you can go for less expensive underlayment, flashing materials, or fasteners for the installation without sacrificing quality.