What's Underfoot? A Quick Guide to Patio Surfaces

Patios and terraces have always been popular outdoor spaces. Whether a Parisian courtyard or a rooftop alcove, only porches and sunrooms beat out these paved (or semi-paved) retreats in a recent survey of my readers as the most ideal outside living space. Let's examine some of the wide variety of patio surfaces.

Patio Stones
Somteimes called flags or slabs, patio stones are flat square or rectangular blocks of pressed concrete. Standard sizes generally include 2' x 2', 2' x 2½' and 2' x 3' (60 x 60 cm; 60 x 75 cm; 60 x 90 cm), with a 2" (5 cm) thickness. They are a very well-known and popular choice for both homeowners and home builders and are favored both for their ease of installation and low price.

Once only grey or greyer, patio stones are now available in a range of colors. Choose a color that blends with your garden or house, or make a patterned floor with two different colors. Patio stones are especially attractive when combined with an edging of a contrasting material. On my web site, I have some suggested patterns combining them with bricks, but you can use a rot-resistant wood such as cedar, landscape rocks, or even aluminum.

You can also purchase patio stones with different surface textures, including those with exposed aggregates. Although these often retain the characteristically consistent thickness that makes for their ease of installation, they are usually somewhat pricier than plain stones.

Stone and Slate
Stone and slate, also called flagstone, are natural materials whose availability is often driven by local resources. They are also usually cut in standard widths and lengths, but the thickness of the pieces will vary with the stone and the cutting. The variable thickness makes the material more challenging to install. Natural stone and slate pieces are more expensive than manufactured patio stones.

Often, people think of flagstones in terms of "crazy paving," that is broken pieces of stone set in attractive, random patterns. This type of patio surface is the most difficult to lay properly. Because the mortar joints of a patio are the weakest point, the stone pieces must be as tight as possible to each other. This requires breaking and trimming the irregular shaped pieces. Experienced installers can break stone by hitting a piece of rebar or pipe that they've placed along the desired break line. I recommend you don't try this at home, boys and girls!

Bricks
Bricks are a popular building material for patios and terraces. A standard brick used to measure 2¼" x 3¾" x 8" (5.7 x 9.53 x 20.3 cm), and be red or yellow. There are many variations these days. Your choice is really personal except for the weather rating. If you live in a cold climate, be sure to get SW (Severe Weather) rated bricks that won't crack in the cold and snow. They cost more than MW (Moderate weather) and NW (Nice Weather -- well, it's officially Negligible Weather, but I think not having freezing cold five months of the year would be very NICE.)

Gravel
Gravel is frequently disparaged as the poor cousin of outdoor surfaces, but gravel courtyards can be not only inexpensive but comfortable and very charming as well. As with other paving materials, gravel also is available now in a range of color choices and textures. You can edge the patio area with rock slabs, bricks or pavers to give your yard a more finished look.

Poured Concrete
Poured concrete surfaces are the most popular professionally installed patios. They're usually less expensive than natural stone, brick or tile to build, are extremely durable when properly installed and treated, can be shaped to any pattern, and can be finished in a wide variety of colors, textures and styles.

Proper installation of a concrete surface includes laying rebar or ¾" steel rods in a cross-hatch pattern in the body of the concrete. Once the concrete has hardened, it should be sealed to resist weather and stains.

With such a dizzying array of patio surfaces available, how can you choose the right one for you? Of course, budget will play a large part. But also consider the style of your house and garden, and the use you'll make of the space. It's harder to place furniture on some of the rough textured surfaces. If you have children riding tricycles, or elderly friends or family who might trip, be sure to avoid anything that might produce an uneven surface, even after some years of settling.

Whatever you select, be sure to spend time on your patio and make happy memories in your outdoor space!