Pros and Cons of Slate Flooring

Young couple sitting on floor choosing new tiles
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Natural slate has the ability to bring unique and powerful beauty to flooring installation, combining the functional durability of hard tile with the awe-inspiring essence of natural stone. However, there are both benefits and drawbacks to the use of this material, which vary depending on the environment where it is being installed. Understanding the pros and cons can help you decide if slate is right for the use and demands of a particular room.

Pros of Slate Flooring

Slate flooring in all its forms has many advantages, but it will perform better in some areas than in others.

Durability: One of the strongest standard natural stone flooring materials, slate has an inherent durability that makes it resistant to cracks, scratches, breaks, and chips. In some environments, it does have to be sealed against stains on a regular basis, but if properly maintained, slate can last for decades and look great without having to be removed or replaced. When sealed regularly it can be an excellent flooring material in bathrooms and kitchens and may provide many years of service where another type of flooring might require several replacements. It is generally a very good flooring material for heavy-traffic areas.

Unique appearance: There are innumerable solid colors and color combinations available when choosing slate floor tiles. The natural beauty of slate can manifest in unique ways in each stone, which means that every floor will have its own unique look, a piece of earth-born artistry.

There is a wide variety of both solid color and multicolored slate materials that are available to match nearly any decorative style scheme you are trying to create. Some types have wildly contrasting colors, while others are more subdued, but the appearance will always be unique. Your options increase thanks to the availability of many grout colors that can complement or contrast with the tiles themselves. This uniqueness can make slate a good choice for highly visible areas, such as entryways or large kitchens. It is less advantageous in rarely seen bedrooms or spaces that are mostly covered with rugs.

Real estate value: Slate is regarded as a relatively upscale flooring material. Although its initial price can be quite high, especially for top-quality materials, slate typically adds real estate value to an entire home. This is especially true when it's installed in locations such as the kitchen and bathroom, or in entryways where it is immediately evident to visitors.

Repairs are possible: In some cases, a tile may be damaged due to violent impact, natural chipping, weathering, or flaking. Unlike other natural stone, slate tiles are relatively easy to remove and replace, though the match will be best if you have saved leftover tiles from the original installation. Because slate tends to vary in color and appearance, it can be difficult to match new tiles to the old if they aren't from the same batch of stone. Don't expect new slate purchased years after the original installation to be a perfect match for color or pattern.

Adapts to radiant heating systems: Slate flooring, as well as other forms of natural stone, are great for radiating heat. That means that it is the perfect medium for radiant below-surface coil heating systems—both hydronic systems that circulate hot water, and electric mat systems. Such systems can be installed underneath the tile, heating not only the floor but also the surrounding environment as the heat rises. This attribute makes slate a good choice for bathrooms, provided it is well maintained to keep it waterproof.

Cons of Slate Flooring

Slate floorings advantages generally outweigh its drawbacks, but there are some things to consider before choosing slate flooring.

High expense: The initial cost to purchase natural slate flooring tiles can be quite high, especially when purchasing the top-quality materials that are most likely to last for decades. In addition to the high cost of the slate itself, which typically averages from $4 to $10 per square foot, the cost of professional installation can add an additional $10 to $15 per square foot. The high cost is a prime reason why slate is often reserved for the most visible rooms in the home.

Difficult installation: Although the installation of slate tile is similar to that of ceramic tile, precise installation is critical with slate due to its brittle nature. Slate tile, like all natural stone, is difficult to cut without special tools. in addition, the subfloor and underlayment preparation must be done very carefully to prevent the flexing that can cause cracking of the grout joints or the tiles themselves. For this reason, it is usually best to have pros install slate flooring tiles.

Slate is a very heavy material, and there are sometimes structural issues when installing it in upstairs rooms. In some instances, you may even need to reinforce the floor structure in order to support the flooring.

Required maintenance: There is a certain amount of maintenance that is required to keep a slate tile floor looking attractive. During installation, the tiles must be sealed both with a penetrating sealer to close tiny pores in the stone, then a barrier sealer to create a protective surface. Depending on the location and how heavily the floor is used, these sealers may need to be reapplied periodically, every year or so.

The grout lines on slate tile are also vulnerable. Any movement in the floor can cause the grout lines to crack, and they can be susceptible to stains, mold, and mildew, especially in damp locations. Regular sealing can help to some extent. It is also possible to completely remove and replace the grout between tiles periodically over the life of the flooring.

Cleft surfaces can be uncomfortable: Slate tiles come in several different textures. While the polished tiles are perfectly smooth, some forms of slate are finished with a rough, uneven (cleft) texture. This form is most often employed in wet environments where the extra traction can help prevent slipping. In other environments, though, cleft slate can be uncomfortable underfoot. Consider this when choosing slate flooring for a particular room.

Cold, hard surface: Although it is a great flooring if you are installing radiant heating, slate can be very chilly underfoot without such a heating system. The coolness may be desirable if you live in a warm climate but is much less so in cool climates. This can be a particular problem in bedrooms, bathrooms, and other locations where you often walk barefoot. This can be offset to some extent by the use of area rugs.

Slate, like all natural stone, is a very hard material, and it is best avoided in rooms where young children or older adults run the risk of falling. China or glass dishes that may survive being dropped on vinyl or laminate flooring will almost certainly break upon impact with slate.

Lack of consistency: The same uniqueness that is one of slate's virtues can also be a drawback. It can sometimes be difficult to obtain the precise design look you want because of variability in the materials, and future repairs can be difficult if you don't have a supply of extra tiles on hand. It is always best to buy plenty of extra tiles to have on hand when you install a slate floor.

Bottom Line

Slate flooring is an extremely durable, beautiful, high-end flooring material that generally adds real estate value to your home, especially in kitchens, bathrooms, and entryways. But before choosing slate, you should also consider its high cost and maintenance needs.