By far the easiest patio to build is one made of bricks set into a bed of sand. A sand base allows rainwater to seep down to tree or shrub roots, and sand lets bricks accommodate the earth below as it settles or shifts with freezing and thawing.
When planning a patio, consider the stability of the ground. Recent landfill more than 3 feet deep or water found within 1 foot of the surface may cause settling problems. If such conditions exist—or if you live in an earthquake zone—consult a landscape architect.
To minimize brick cutting, lay a dry run around the patio perimeter before excavating, adjusting the patio dimensions to incorporate as many whole bricks as possible. Be sure to plan for a permanent edging (page 122), required to keep sand-laid bricks from shifting. Chop out tree roots near the surface that would prevent bricks from lying flat. Before digging, check with a building inspector to see if you must erect a silt fence to keep eroded soil on your property.
Usually, 2 inches of sand on well-tamped earth offers adequate drainage. Dense clay soils or heavy rainfall, however, often require the added drainage of a 4-inch layer of gravel under the sand. Use the estimator on page 128 to figure the amounts you need. To prevent sand from sifting down into the gravel, cover it with 15-pound roofing felt or 6-mil polyethylene sheeting punctured to let rainwater through. If drainage is a particular problem, slope the sand bed away from the house about 1 inch every 4 to 6 feet. Perforated drain tile or plastic tubing laid in the gravel layer helps drain water away from wet spots.
Untextured, exterior-grade bricks are best; rough or grooved surfaces collect water that can crack bricks when it freezes. But avoid glazed bricks, which become slippery when wet. “Bricks” of molded concrete, which come in a wide array of colors and shapes, offer an alternative to traditional clay brick.
Patterns of bricks laid tight against one another control weeds better than bricks laid with gaps between them. For a gapless patio, buy special paving bricks exactly half as wide as they are long.
Other paving bricks are sized for mortar joints between them. The gap both accentuates the pattern and channels rainwater down the long side of the brick—away from the house, if you align the long edges with any slope the site may have. Plastic sheeting laid on the sand bed before the bricks are laid helps keep weeds from growing in the gaps, and sand swept into the gaps keeps the bricks from moving.
Using a brickset
To cut a small number of bricks, use a wide chisel—called a brickset—and a 4-pound maul. Draw a cutting line on the brick, then cushion the brick on sand or a board. Hold the brickset vertically with the beveled edge facing away from you and strike the tool sharply. Then tilt the brickset slightly toward you and strike again, thus splitting the brick. Practice on a few broken bricks before you cut the bricks you will use.
Before excavating, establish the locations of underground obstacles such as electric, water, and sewer lines, and dry wells, septic tanks, and cesspools.
Wear eye protection when cutting bricks. A dust mask is recommended when trimming brick with a circular saw. Gloves help prevent blisters and abrasions.
Scoring bricks with a circular saw
Large numbers of bricks are more easily cut with the help of a circular saw fitted with a carbide masonry blade. Hold the brick in a simple jig made of 2-by-4 scraps, spaced a brick’s width apart and nailed to a piece of plywood. Set the saw for a ¼-inch cut, then slowly guide the blade along the cutting line, grooving the brick. Make a matching groove on the other side, then hold the brick in your hand and break off the unwanted portion with the blunt end of a mason’s hammer (inset).
Laying out a rectangular site
Drive reference nails into the wall of the house to mark both sides of the patio. Use the method shown on page 130 to establish positions for 2-by-2 stakes opposite the nails and 2 feet beyond the end of the future patio. Tie string between the nails and stakes to establish side boundary lines for the patio and mark each string where the patio will end. With a helper (above), stake a third string so that it crosses the marks you made on the side boundary lines. To excavate the area, first dig a trench along the boundary lines. Make the trench deep enough to accommodate the bricks, sand, and gravel if any. Work in parallel rows, back and forth between the perimeter trenches.
Laying out an irregular shape
Draw the patio on graph paper, with each square representing 1 square foot. To estimate the area of the patio, assign a rough fractional value to parts of squares inside the outline. Then add up the full squares and the fractions. Use this figure when buying brick, sand, and gravel. Lay out a garden hose in the shape of the patio, then outline the perimeter on the ground with a dispenser of powdered chalk. Trench around the perimeter, then excavate.
Edging the perimeter
First, compact the earth inside the excavation with a tamper. Around the perimeter, dig a narrow trench such that the top of a brick stood on end in the trench will be even with the patio surface. (If a side of the patio will border a flower bed, let the edging extend 2 inches higher.) Tamp the bottom of the trench with the end of a 2-by-4, then stretch reference strings as guides for aligning the tops of the edging bricks with one another. Next, stand bricks upright around the perimeter (left), with their top edges touching the strings. Press earth against the bricks to hold them up. Add washed gravel as necessary, distributing it evenly over the surface with a rake. Cover the gravel with roofing felt, or polyethylene sheeting that has been punctured with drainage holes at 4- to 6-inch intervals. Spread a 2-inch layer of sand over the bed. Dampen the sand, then tamp the surface again.
To make a sawtooth pattern with teeth protruding 2 inches above the patio surface (above), set the bricks at an angle of 45° in the trench. Other choices for edgings include rot-resistant redwood or pressure-treated 2-by-6s (above, right) set in a narrower trench, or upright bricks set in a curve (right) for a rounded corner. To lay out a curved corner, use a level to align the tops of the bricks.
Laying the bricks
Use a reference string to help align bricks in the pattern you choose for your patio. Begin a herringbone pattern, for example, with a brick set at a 45° angle to the edging in each of two adjacent patio corners. Tap the bricks into the sand with a rubber mallet to make them flush with the edging bricks. Stretch a string between two spare bricks, set just outside the edging, so that the string passes over the corners of the two corner bricks. As you set bricks in the first row, align corners with the string. Use the mallet or adjust the sand bed to keep the bricks even with one another. To begin a new row, lay a brick at each end as a guide for positioning the reference string. Fill in the row, smoothing any sand you may have disturbed. Repeat for each row. Fill triangular spaces along the patio edges with brick that you have cut to fit, then gently sweep sand into any gaps that remain. Add more sand if necessary after it rains.
Starting with half bricks
Loop a garden hose around the tree to mark inner and outer perimeters for the patio. Make the inner circle at least 3 feet in diameter to avoid wide gaps between the half bricks used in the first two courses. Excavate and edge the area to be paved, then prepare the sand bed. Cut half bricks for the first course and tap them into place with a rubber mallet, wedging the inner corners of the bricks tight against each other (left). Use a level to align the tops of the bricks. Trim the last half brick in each course as needed for a snug fit. Lay a second course of half bricks against the first.
Setting the whole bricks
Place concentric circles of whole bricks in the sand bed so that their inner edges touch at the corners and butt against the preceding course. Tap each brick into place with a rubber mallet. Use a 4-foot mason’s level to align the brick, adding or removing sand as necessary. Continue laying whole bricks in concentric circles out to the edging.
Filling gaps at the edge
Mark a brick to fit each oddly shaped nook along the patio’s outer perimeter. Cut the brick with a brickset as shown on page 120, then trim as needed by chipping it with the sharp end of a mason’s hammer. Set the brick into place with a rubber mallet. Gently brush sand into the gaps between bricks, repeating the process as necessary to refill the cracks after a rain.
Scribing scallop arcs
Use the edging of a sand bed to establish a base line for drawing semicircles in the sand. Arcs that have a radius of 24 inches and are spaced with their centers 60 inches apart make an attractive pattern. Scribe arcs across one end of the sand bed, with partial arcs at the sides if necessary. Stretch a string between two bricks so that it crosses the tops of the arcs in the first row (right). Kneeling on boards to avoid disturbing arcs already drawn, scribe another row of arcs with centers midway between those in the first row. A framing square helps in marking these centers and those in subsequent rows. Use partial arcs in the last row if necessary.
Paving the scallops
Arrange whole bricks along each arc (left), then with a partial brick, start filling each scallop at the narrow space between arcs. Half a brick, followed by three-quarters of a brick in the next course, works well with 24-inch arcs. Pave the rest of each scallop with whole bricks laid in slightly curving rows (inset). Fill partial scallops with whole bricks and any cavities with cut bricks or sand. Sweep sand into any gaps that remain.