The term flagstone refers to large, dense, moisture-impervious thick, irregular-shaped stones typically used in exterior applications. Flagstone is typically a form of sandstone, slate or quartzite broken into large, jagged chunks varying in thickness from 1/2 to over 1 inch. On the other hand, limestone is a porous, far less durable natural stone. Whether it's a walkway, the deck area of a pool or spa or a patio, there are significant decision-altering differences between flagstone and limestone.

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Flagstone is jagged and multi-shaped.

Durability and Maintenance

Flagstone generally requires far less maintenance than limestone. Flagstone repels most organic stains and weathering and only requires periodic cleaning with a pressure washer or soap and water to maintain a fresh, new look. On the other hand, limestone stains easily, is susceptible to the elements, chips and cracks easily and requires frequent, labor-intensive sealing and cleaning. Because it can withstand heavy weight loads and use, high traffic areas such as driveway and walkways usually feature flagstone. Limestone is an easily damaged, special decorative material suitable for decks, pool details and patio areas.

Cost

The do-it-yourselfer should consider the different labor and material costs between flagstone and limestone. Limestone material may initially cost several dollars more per square foot than flagstone, but the additional labor required in installing flagstone may gobble up any potential savings. The do-it-yourselfer should get a labor and material estimate when considering the cost difference between limestone and flagstone or consider the extra DIY labor involved with flagstone installation. Limestone is generally considered more DIY-friendly than flagstone.

Appearance

There are key design and architectural differences between flagstone and limestone. For example, limestone is typically beige or gray-toned. Flagstone conveys an earthy look, with shades varying from lustrous, shiny, metallic grays (quartzite flagstone), oranges (sandstone flagstone), purples and greens (slate flagstone) and many others. The design rule of thumb is that flagstone generally projects a rustic, textured, multicolored appeal; limestone conveys a subtle, design-neutral look.

Additional Components

Additional components, such as special edged tread pieces and pre-fabricated wall caps, are available for both limestone and flagstone. However, the availability may depend on the particular limestone or flagstone selection. Be sure to research availability if you need additional pre-fabricated components.