Excavating - Building Patios
Tools: Garden edger, sod lifter, mattock, spade, shovel, 4-foot level, straightedge, gloves
Excavation simply means digging.
Use the right tools to make the job as efficient as possible. A garden edger quickly cuts a straight line through sod.
A shovel with a curved blade is for digging; don’t confuse it with a spade, which has a flat back and is designed to cut the edge of a trench. To remove sod, break up the surface with a mattock, which looks like a pick. If your patio is large, you might want to use a sod lifter, which has a curved handle and will save you much bending. When excavating, make sure you dig out all roots and organic material, which tend to decay, collapse, and undermine your patio. The depth you dig depends on the type of patio: 8 to 9 inches for bricks or pavers set on a sand-and-gravel base, 8 to 9 inches for a concrete slab patio, and 11 to 12 inches for bricks or stones set in mortar on a concrete slab.
Step on the edger to cut straight into the sod. Work your way along the layout lines. To remove wide areas of sod, cut 1-foot strips with the edger. Lift the sod with a shovel or sod remover. Hold the blade at a low angle. Put weight on the top of the tool to cut between the soil and the roots and pry it loose.
1 Lay out the shape. Set up batterboards and use mason's line to lay out the outline of the patio. Use powdered chalk to mark the outline of the installation.
Check for any septic system, gas, water, phone, cable, and electrical lines before digging.
In small areas, rolling up the sod can be a quick way to remove it. If you're excavating for a large patio, however, it may be easier to break up the sod and toss it in the wheelbarrow with the rest of the dirt. The tool to use for this job is a flattened pick called a mattock. Let the tool do the work. Swing the blade up, bring it downward with some force but loosen your grip slightly, and let it hit the ground under its own steam. You'll get "mattock elbow" if you try to slam the tool into the ground. Medically speaking, it's the same as tennis elbow, and it hurts.
Checking the slope
Patios should slope away from the house so they don't channel rain toward the foundation. The typical slope is Vfe inch to Vi inch per foot, depending on rainfall; ask your local building officials for the required slope in your area. Check the slope by propping a wedge underneath one end of a level.
If the slope should be Vi inch per foot, for example, the wedge would be 3 x Vi or % inch thick on a 3-foot level. It would be 4 x Vi or 1 inch thick on a 4-foot level.
Remove the sod from the excavation. Roll the sod and remove it from the area to be excavated. Put at least some of it in a cool, shady place and use it to patch the lawn when you finish the project.
Check with a level. Rest a level on a straightedge and check to see if the trench is level. If the excavation is supposed to slope for drainage, put a wedge between the straightedge and the level equal to the desired slope over the length of the level.
Dig a trench. Work along the layout lines, measuring down from them to dig a trench to the desired depth of the excavation. Usually the excavation slopes as it runs away from the house and is level from side to side. The directions for individual projects later in this chapter state the proper slope. Dig the trenches at the recommended slope.
Dig between the trenches. Large excavations, such as those for patios, will have a grid of layout lines, and you should dig a properly sloped trench under each one. Once you have, dig out the space between the trenches. Smooth by pulling a 2x4 along the surface and check with a level, as in Step 5. Regrade as needed and compact.
Laying a running bond pattern - Building Patios
Laying bricks is similar to laying pavers, except you need to pay more attention to alignment. A running bond is one of the simplest patterns to create. Every second row begins with a half brick, offsetting the joints from row to row.
1 Stretch a guideline. Put a brick at the beginning and end of the first course. Stretch a line along the edges of the brick as a guide, anchoring the line with another brick, as shown.
2 Lay rows of bricks. Lay a row of bricks or pavers. If they have no tab on the edges to space them, cut thin pieces of plywood to use as spacers. Embed the bricks in the sand with a rubber mallet. Start the next row with a half brick to stagger the joints. Alternate, starting one row with a full brick and the next with a half brick. Check for high or low spots with a 2x4 and add sand or tap bricks in place as necessary.
3 Trim bricks to fit. To cut a brick, score a line around the entire brick with a brick chisel and a 3-pound sledgehammer. Position the brick chisel in the scored line, then snap off the cut with a sharp blow of the hammer. Always wear safety goggles and work gloves when cutting brick or pavers.
4 Fill the joints with sand.
Once all the bricks are laid, sweep a layer of fine sand, often sold as mason's sand, over the surface with a broom or stiff brush to pack the joints between the bricks.
5 Compact the surface.
Compact the entire surface with a power tamper. Some manufacturers recommend that you spray the surface with water to wash and fill the sand into the joints.
Laying a basket-weave pattern - Building Patios
Basket-weave patterns require no cutting if you plan the borders correctly. Start in the middle of an edge and lay three short rows to create a stepped pyramid. Once the rows are laid, work diagonally, filling in the steps until you cover the surface.
1 Snap a line down the middle. Lay out the patio, put the edge restraints in place, and install and level the sand bed. Snap a chalkline down the center of the sand bed.
2 Begin layout at the center line. Put the first brick in place against the edging, with the long edge on the centerline. Make sure it's square. Lay six bricks on each side of the line in the pattern shown, alternating the orientation of each pair.
3 Lay the second row. Begin the second row before you finish the first. Starting at the centerline, place the bricks following the pattern, laying only four bricks on each side of the line, making sure that the orientation of each pair is perpendicular to the bricks in the first row.
4 Lay the third row. Install two bricks on each side of the line to create a stepped pyramid pattern. From now on you'll lay bricks in the steps, which will keep the bricks aligned and square.
5 Follow the pattern. Start at the edge restraints and nestle two bricks in the corner created by the restraints and the bricks already laid. Work your way up the stepped sides of the pyramid on each side. Continue laying in a stepped pattern to lay the entire surface. Cut end pavers as needed to fit against the restraints.
Laying a herringbone pattern - Building Patios
Herringbone is fancier than running bond but no border to lay. It is, however, more time-consuming because so many bricks need to be cut. The finished effect is eye-catching, and many do-it-yourselfers feel the result is well worth the trouble. Measure to make sure you get the right size of brick: The true (rather than the nominal) length of the brick must be twice the true width for the pattern to work.
1 Start in a corner. Lay out the patio site with batterboards or a builder's level. Set a trial run along each edge to make sure the bricks or pavers fit and adjust the borders if necessary. Starting at one corner, lay a pair of full bricks at right angles.
2 Continue along the edge with half pavers or bricks.
Install half bricks next to the full pavers in the corners, as shown. Spread piles of pavers along the path so you don't have to make trips back and forth as you lay the pattern.
3 Lay perpendicular bricks.
Lay a leg of full-length bricks or pavers at right angles to each other in a stepped pattern, as shown. Once a leg is properly laid, bed the bricks in the sand with a tap from a rubber mallet.
4 End the first leg and start the next. End the first leg along the perimeter with a half brick. Then lay another stepped leg of full bricks, alternating their long and short sides at right angles to each other.
5 Continue laying stepped legs, finishing each end of every other leg at the perimeter with a half brick. After the patio is laid, sweep sand in between the bricks. Then compact the patio with a power tamper to embed the bricks and spread the sand between the joints.
Laying a diagonal herringbone pattern
Diagonal herringbone is a more complicated pattern to lay. It involves cutting numerous bricks or pavers to fit. Lay the pattern using full bricks, then make ail the cuts to fill in at the edges. Measure carefully for the location of the starter row and check your work constantly as you proceed.
1 Lay a small sample. Lay nine pavers as shown. To make sure the layout is square, draw a line at a 45-degree angle across one brick, as shown, and connect the corners of the other bricks in a straight line. Measure the distance between the two lines. Stretch a mason's line this distance from the edge.
2 Lay the first four bricks.
Make sure the line you stretched in Step 1 is parallel to the edge restraints; reposition if necessary. Lay two bricks, as shown, so that the outside corner of one and the inside corner of the other fall along the line. Lay two more and make sure they are square.
3 Continue the starter rows.
Snug two bricks up against the first bricks, aligning the corners as in Step 2. Follow the line all the way across the surface you're covering.
4 Lay single rows. The next row and all subsequent rows are single rows. Align them by tucking the second brick of the row in place. Next lay the first brick of the row, then lay the remaining bricks in the row.
5 Check against a straightedge. Lay two rows, then stretch a line across the surface.
The corners of each block should just touch the line. If not, adjust the bricks so that they do. Continue laying rows and checking the alignment until the surface is covered with whole bricks. Cut bricks to fill in the spaces at the edges of the pattern.