Mortar, concrete, and grout - Building Patios
Concrete, grout, and mortar look much the same, do much the same thing, and come in bags that look pretty much the same. Concrete is used to make concrete patios or the base for a mortared installation; mortar holds bricks to each other or to a concrete pad; and grout is put between tiles once the patio is laid. Here’s a quick look at what goes into each:
Cement is made by grinding a naturally occurring limestone that contains clay. Portland cement is made by baking cement at 2,700 degrees then pulverizing it. Neither cement is strong enough on its own, and both are mixed with some combination of sand, gravel, and lime to make concrete, mortar, and grout.
Concrete is made of cement and fine and coarse aggregates; the fine aggregate is sand and the course aggregate is gravel. Although concrete is hard, as anyone who has ever scraped a knee knows, it’s also brittle. A metal mesh usually runs through the middle of the pad to knit it together if it should ever crack.
Mortar is a mixture of cement, lime, and sand. Masons often refer to it as an adhesive, but it doesn’t come in a bottle or can, and it is neither a glue nor a mastic. It’s a cement-based mixture designed to adhere a brick, stone, or paver to a similar object or to a concrete pad.
Grout is a 1:1 mixture of cement and sand; it also may contain lime. It’s finer than mortar to create a smooth surface between tiles on a floor or wall. Although similar in content to mortar, the proportions are different, and grout would not work well if you tried to use it as mortar.
Cement is a naturally occurring limestone that is the basis for most of the mixes used in masonry. Concrete is a mixture of cement, sand, and gravel. Grout is made of equal parts of cement and sand and is used to seal between tiles. Mortar is a mixture of cement, lime, and sand and is used to hold brick, stone, and tile in place.
Cutting brick, tile, pavers, and stone - Building Patios
Patio edges often have to be cut to fit. You can make the cuts several ways, and the technique is similar regardless of the material. The most inexpensive tool (called a wetsaw) looks like a mini-tablesaw that cuts with a diamond blade bathed in water. Most pros use a heavier-duty saw with a top-mounted blade, which looks somewhat like a power miter saw. It, too, cuts with a diamond blade that is bathed in water, but it is more powerful than the small version.
Many patterns-such as a running bond-start or end each row with a half-brick. A lot of cutting is involved, and often the best way is to make the cuts after the bricks are laid, using a tool called variously a drysaw, cutoff saw, or quicksaw. This saw can be run dry or wet depending on the material you’re cutting.
When cutting pavers or brick, the drysaw (which is how it will be referred to in this book) is used without water to prevent staining the surface material. Whatever name you choose to call it, the tool looks like a large circular saw but is usually gasoline powered. Guide it along the intended edge of a patio after all the bricks, pavers, or stones are in place.
Power tools make quick work, but hand tools have their place too. For example, you’ll need brick chisels and hammers when cutting stone pieces that may not fit on a power tool and that look best with a slightly ragged edge. A drysaw speeds installation of patios.
Unless you're doing a very large installation, it's probably a good idea to rent the tool. A drysaw operates much like a circular saw, but you need to take some lessons on safety and operation from the rental store and practice with the tool before you start using it for your project.
Using a tile saw with a bottom-mounted blade
1 Lay out the cut. Saws with a bottom-mounted blade have a limited cutting depth, approximately 1 inch deep, and are generally designed for cutting tile only. Draw a layout line with a grease pencil, marking where you want to make the cut. Subtract the width of the joint from the overall size of the tile.
2 Make straight cuts. Put water in the tub below the saw. Set the fence so that the layout line on the tile is lined up with the blade. Push the tile into the blade with slow, steady pressure.
3 Cut angles. A miter gauge cuts angles. Loosen the knob and turn the miter gauge until the layout line aligns with the blade. Put the brick, paver, or tile against the angle guide or miter gauge. Tighten the knob to lock in the angle and push the miter gauge forward to cut with slow, steady pressure.
Cutting with a saw with a top-mounted blade
1 Lay out the cut. An overhead saw makes deep cuts, as much as 3 3/4 inches. The saws for brick and tile are different, largely because of cutting depth; make sure you rent the one you need. Whichever you have, fill the tub with water. Put the brick, paver, or tile in place and draw a layout line to mark the cut. Subtract the width of the joint from the overall size of the tile.
2 Make straight cuts. With the saw off, put the paver, tile, or brick against the lip on the sliding table. Ease the table toward the blade. Align the layout line with the blade and fasten the rip guide next to it. Turn on the saw and push gently and slowly to make the cut.
3 Cut angles. Align the layout line with the blade. Put the miter gauge attachment on the table, set it to match the angle of the brick, paver, or tile, and lock it in place against the material you're cutting. Turn on the saw and feed the table toward the blade to make the cut.
Cutting pavers with a drysaw
1 Lay out the edge on the ground. Snap a line on the ground showing where the paving will end. Lay pavers or brick up to the line.
2 Lay out the edge on the pavers. Putting the pavers in place covers the layout line, so snap the cut on top of the pavers. Spray lacquer on the line to keep it intact as you work.
If a paver needs to be trimmed to fit, put it in place without cutting it.
Use a drysaw to cut straight lines or curves after the paving surface is in place. Because you can cut more than one brick, tile, or paver at a time, it’s efficient, and as long as you can follow your layout line, you’re less likely to make small measurement mistakes.
The saw raises an incredible amount of dust. Make sure to wear a dust mask, close windows in the house, and move cars and items that can be damaged with dust away from the job site. Because of the dust raised, make sure you’re cutting to a layout line that is highly visible-bright chalk works well. Spray the line with lacquer before you cut so the dust doesn’t erase it as you work. Sweeping and compacting sand into the joints will remove both the lacquer and the chalk.
3 Angle the saw slightly.
Most drysaws can be run wet or dry. Run it dry so that the combination of dust and water doesn't stain the surface of your work. Start the saw and hold it at a slight angle so the bottom of the paver or brick will be cut a bit shorter than the top.
4 Make a first cut. Guide the saw along the layout line, cutting into the surface. Don't try to make the full cut in a single pass. Let the saw cut as deep as it will go on its own. Cut along the length of the entire line.
5 Make a second cut. Guide the saw along the first cut, holding it at the same angle and letting it cut as deep as it wants to go. Repeat until you cut entirely through the brick or paver.
Cutting brick or flagstone by hand
1 Lay out the cut. Mark the cut line on the material with a pencil or scratch it on the surface with a nail. Make sure the size of the line takes the space between the flagstone or brick into account.
2 Score along the top face.
Guide a chisel along the layout line, striking the chisel, moving it, and striking again. To make sure the line is straight, strike the first blow at one edge of the material and the second blow at the opposite edge. Alternate back and forth until the line meets in the middle.
3 Score the sides. Draw lines on the edges of the material, showing where you want to cut it. Use a straightedge to guide the layout lines. Angle the lines slightly, a bit smaller at the bottom than at the top of the material so it will fit snugly against the edging. Score along the lines.
4 Score the back. Draw a line on the back, connecting the lines you drew on the sides. Score the line the same way you scored the line on the front of the material.
5 Split the material. Put the material you're splitting on the ground, which will absorb the shock. Put the chisel in a score line and strike with a 3-pound sledge. Move the chisel along the line, striking until you split the material.
Removing old concrete - Building Patios
Tools: Jackhammer with chipping and cutting bits, safety glasses, dust respirator, work gloves, ear protection, wheelbarrow
If an existing concrete pad is sound, you can often put a brick, stone, or paver patio on it. But cracks, holes, flaking, or an uneven surface are problems that will eventually work their way through a new surface. A new crack will eventually reappear right above the old one no matter how much repair work you do in advance.
To correct problems between control joints-lines cut through the surface at regular intervals when the concrete is wet-you may be able to limit the concrete taken out to the area between the joints. If not you’ll have to remove the entire surface.
Removing concrete is just plain hard work, and you may want to hire someone to do it. To do it yourself, rent a jackhammer, at the very least, and have a plan to get rid of the broken-up material.
Jackhammers are simple to operate, and electric models don’t require the expense, noise, and bother of big compressors required for pneumatic hammers. Technically, jackhammers are demolition hammers. (Chipping hammers are smaller and designed for work on walls and concrete ceilings. Rotary hammers are smaller yet and are little more than drills that twist as they pound.)
Rent a 40- to 50-pound electric demolition hammer and let the weight of the tool do the work.
The biggest problem you’re likely to face in removing concrete is the wire mesh that runs midway through the slab, which is put in as the concrete is poured in order to tie the concrete together. You’ll have to cut through it with the hammer in order to break the concrete into manageable chunks.
Cutting concrete safely
A jackhammer makes short work of demolishing a concrete pad, but it's noisy and provides a real workout. Take the time to learn how to use it and follow all safety instructions.
A jackhammer is designed to demolish material, so treat it with respect. Wear a dust mask to keep the dust out of your lungs and goggles to protect your eyes. Wear ear protection to shield your ears from the noise.
Don't operate a jackhammer in the rain or on a wet surface. Not only is the surface slippery, the water may damage the tool or cause an electrical shock. Make sure you will not be cutting through live electrical wires or conduit.
Use only an extension cord rated for outdoor use and one that is rated to handle the amperage drawn by the hammer. Plug the machine into a properly installed GFCI to lessen the possibility of shock.
Getting rid of the debris
Concrete is heavy and results in a lot of weight and jagged pieces when it's broken up. Use a jackhammer to break the concrete into manageable chunks that won't strain your back when you load them into a wheelbarrow or pickup. Be reasonable when loading a wheelbarrow or pickup and do not overload it.
The old concrete can be used as landfill if you need to fill a hole or build up a berm. It also can be disposed of at a municipal waste facility for a fee. Check with local codes to make sure you are aware of the restrictions on disposal in your community.
Operating a jackhammer
1 Insert the tip in the hammer. Make sure the hammer is unplugged. Swing the retaining arm back toward the handle. Put the cold chisel tool or the cutting point in the socket and swing the arm back in place. The cutting point usually works best when pounding through an old surface.
2 Set the chisel on the surface. Plug in the tool and put the cutting edge near an edge or near the damaged area of the surface you want to remove. Most tools have a "no load" striking safety that keeps the hammer from running unless it's on a surface. You may have to push down firmly on the tool to start its motion.
3 Break up the concrete. Let the weight of the tool do the work-trying to push on it will wear you out without getting the job done any sooner. Move across the surface, breaking it and creating new cracks as you go. Follow the cracks with the |jackhammer to break up the concrete more quickly. About 2 inches into the pad, you'll run into the wire reinforcing mesh. Cut through it with the jackhammer, switching to a wider tip, if necessary, to break the concrete into manageable pieces.
4 Haul away the rubble. Disposal of the rubble will be your hardest job. You can use it as clean fill somewhere in your lot or have it hauled away on a truck. Load the rubble into a wheelbarrow and haul away.