The debate between slate roof tiles and synthetic alternatives has been raging on for a while. Slate comes from natural stone that is mined and cut into size. On the other hand, synthetic slate is composed of recycled materials such as rubber, plastic, and mineral dust.
The aim of this article is not to tell you which of the two is better. We do not believe it is clear-cut as that. Instead, we will compare both in different categories to help you make your own informed choice. It is your roofing needs that will dictate which option fits you well, after all.
Before comparing them, let us define the two to ensure we are all on the same page.
What is a Slate Roof?
Slate tiles come from mined natural rock. After mining, they are cut into square tiles that are ready for installation. Slate tile roofs are popular for their long lifespan and natural beauty characterized by variations in texture and color.
What are Synthetic Slate Tiles?
Synthetic slate tiles are imitations of natural slate made from recycled materials such as rubber and plastic. They resemble the real thing down to the chisel marks, and it is difficult to tell the two apart unless you are an expert.
Natural Slate Roof vs Synthetic Slate Tiles
The following table compares natural and synthetic slate tiles in summary.
Type | Natural Slate | Synthetic Slate |
---|---|---|
Material | Natural Slate | Rubber, plastic, asphalt, fiber cement |
Lifespan | 100+ years | 30 to 50 years |
Weight | Heavy | Lightweight |
Durability | Highly weather resistant but can crack or break under impact | Rubber and plastic could curl or crack |
Appearance | Classic gothic look | Mimics the look of natural slate |
Environmental impact | Naturally occurring and recyclable | Made from recycled materials |
Warranty | contractor’s workmanship warranty | lifetime limited material warranty and contractor’s workmanship warranty |
Difference 1: Longevity
Longevity is the ultimate measure of a roof's value. Installing a roof is a costly affair, and you should not have to incur the cost of reroofing.
Natural slate is one of the most long-lasting roofing options available. The expected lifespan falls between 75 and 100 years, but it can last longer if properly installed and maintained. We have even come across some houses built in the 1800s that have their slate roofs still intact.
It is hard to talk about the longevity of synthetic slate tiles since they are a new product. But manufacturers claim that they can last anywhere between 30 to 50 years. The problem is there are no synthetic tiles that are 50 years old. Nevertheless, they are unlikely to last as long as natural slates.
Difference 2: Weight
Natural slate tiles are heavy, weighing around 800 to 1500 pounds per square. Your roofing deck cannot withstand that amount of weight without some form of reinforcement. Therefore, we recommend hiring a structural engineer to help you with that.
On the other hand, synthetic slates are lightweight since they consist of materials such as rubber and plastic. They weigh a quarter the weight of their natural counterparts and are even lighter than asphalt shingles. Unlike with natural slate, your roof will not require reinforcement before installation.
Difference 3: Durability
Natural slate tiles are durable and will withstand extreme weather conditions such as hail, high winds, and heavy rain. They are also waterproof and, therefore, not prone to algae or mildew growth. However, they are brittle and will easily break under impact.
The brittle nature of natural slate tiles makes it challenging to walk on the roof during cleaning and maintenance. You also have to watch for overhanging trees since branches can fall and crack or break the tiles.
Synthetic slate tiles are more impact-resistant compared to natural slate. However, there are some durability concerns. For instance, rubber and plastic are flexible and could curl and crack. Also, they can disintegrate over time, especially when exposed to harsh weather conditions.
With that said, it is imperative to note that synthetic slate tiles have only been around for a few years. Although they have performed well in short-term tests, they have not undergone testing in actual conditions.
Similar synthetic products manufactured in the 80s and 90s are no longer in the market after extensive failures. Will synthetic slate tiles suffer the same fate? Only time will tell.
Difference 4: Appearance
Slate tiles have a classic rustic look. Shaped by hand, they have a unique appearance and will make your roof stand out from the rest. Moreover, they complement any style of architecture and are available in a variety of colors.
Synthetic slate tiles mimic the look of natural slate rather successfully. They even have chisel marks to make them appear like they are hand-shaped. In fact, you cannot tell the difference between the two when standing on the ground.
Difference 5: Price
Slate tiles are one of the most expensive roofing materials on the market. Prices start at $5 for materials alone, but you can pay as high as $15. The cost shoots to $10 to $30 per square foot when you factor in installation costs.
Although natural slate tiles are expensive to buy and install, they provide a lot of value in the long term. Repairs are rare, and you may never have to install another roof in your lifetime.
Synthetic slate tiles are a cheaper alternative. It will cost you between $3 and $16 per square foot to install them. That will depend on the type of materials. Labor will cost you $3 to $5 per square foot.
Difference 6: Warranty
Natural slate tiles are mined from the ground, not manufactured. Therefore, you cannot get a warranty on the materials. However, the contractors will offer you a workmanship warranty to cover failures after installation.
Synthetic slate is a manufactured product and usually has a lifetime limited material warranty. The length will depend on the manufacturer, but many offer a 30 to 50-year warranty.
Difference 7: Ease of Installation
Natural slate tiles are heavy and brittle. Therefore, installing them is a labor-intensive process that requires specialized knowledge and skills.
Not many roof installers have experience installing slate tiles. So, we recommend screening your contractor beforehand to ascertain they have installed them before. Some testimonials could also help put your mind at ease.
Synthetic slates are easier to install. However, it would be best if you didn't try installing them by yourself either. An experienced contractor is crucial here too.
Difference 8: Availability
Natural slate tiles are mined. Naturally, there will be instances during the year when their availability will dip. On the other hand, synthetic slate tiles are manufactured. Therefore, they are available throughout the year.
Difference 9: Environmental Impact
Natural slate tiles are environmentally friendly. Extracting and cutting them does not include artificial materials, chemical products, or furnaces. As a result, no harmful gases get into the atmosphere. Natural slate is also reusable and recyclable.
Synthetic slate tiles are also eco-friendly since they consist of recycled materials. You can also recycle the tiles at the end of the roof's usable life.
Conclusion
Natural and synthetic slate tiles may look alike but have significant differences. The recent emergence of synthetic alternatives addresses the cost and weight issues associated with natural slate tiles. However, the longevity and durability of natural slate tiles remain unmatched.
There is still much we do not know about synthetic slate tiles. For now, they are a good alternative if you are looking for a cheaper and lighter roofing option. But natural slate is a long-lasting and durable option if you can bear the high cost.