Once they've cured for at least three days, remove the stakes from inside of the remaining sections black squares and complete them.
Move a strikeoff example above- a straight wood 2x4 across the form to level the concrete. On large jobs, do this batch-by-batch, rather than after all the cement is placed. Move the board slowly along the form, using a side-to-side, sawing motion; be sure to make two passes.
Even on narrow forms, two people will make the work faster and more efficient. If necessary, a third person can shovel extra concrete into any corners to save time. If you're working on a very small walkway leading to your patio, you can skip this step. After striking off, use a darby or bull float-depending on the size of your project-for the initial finishing, to smooth down high spots and fill small hollows left after striking off.
Use the darby above, left on small DIY concrete projects. Move it in overlapping arcs, then repeat with overlapping straight, side-to-side strokes. Keep the tool flat, don't let it dig in. For larger jobs, use a bull float above, right. Push it away from you with its leading edge raised slightly.
Pull it back nearly flat; overlap your passes. Giving your Do It Yourself concrete slab or sidewalk a curved edge will help it resist chipping and prevent stub-toes or tripping accidents. To edge the cement, begin by running a mason's trowel between the concrete and the outer edges of the slab form above-inset.
Follow with an edger above-right. Run it back and forth to smooth and compact the concrete. Unless the tool has a toboggan end, raise the leading edge slightly as you move it. Large slabs of concrete will crack. To control patio cracks you need to set joints with a 1" deep jointer with a straight guide board to make control joints above. Kneel on a board to reach the middle of a wide slab.
Depth of control joints should be one-quarter of the slab's thickness. Control joints can be made at intervals of about 1. Jointed sections should never be more than 1.
Measure along the forms to locate the joint and mark them with a pencil. Any edging or jointing marks can be removed by floating- which is next! Now comes the fun part of working with ready mix cement , well, we think floating concrete is fun. After the water sheen has disappeared from the concrete, but before the surface has become really stiff, float with a wood float or a magnesium hand float. The latter gives a smoother surface.
With air-entrained concrete, what we deliver use a magnesium float- a wood float can tear the patio surface. With both types of float, hold the tool flat on the surface. Once again, to reach the middle of a large slab, kneel on boards and then finish over the board marks as you work backwards. CAUTION: Don't use a steel trowel on outdoor surfaces, unless you are going to broom-finish afterwards; it creates a very slick surface that can be dangerous when wet.
So positively do not use a steel trowel on a patio next to a pool. Patio slabs need to be moist cured to keep their surfaces from drying too quickly- especially in our high desert heat of Twin Falls, ID. If the surface dries too soon, it will be weak and may later become powdery or crumble away.
Cure your concrete by keeping it wet. Concrete is durable and long-lasting, and brick is attractive, but the best option we've found is bluestone. These multihued slabs are the perfect pavement.
They have a delicate and subtle color that weathers nicely, and they never crack. One downside is that bluestone is not easy to work with. It's heavy, at approximately pounds per cubic foot. Choose the dimensions for your patio, then mark them off by driving batter boards H-shaped stakes a couple feet outside the corners of the four boundaries [1]. You want them far enough away from the perimeter that you won't need to move anything during construction.
Stretch mason's string between the stakes to mark the edges of the patio. Clip a line level to the mason's string to ensure an accurate horizontal reference. Use a square-nose shovel to create the perimeter of your hole [2]. Cut the hole eight inches deep—enough to accommodate the layers of support beneath the stones and the stones themselves.
The sides should be clean and square. Check the bottom of the hole for level with a four-foot level. If you don't have one, you can place a smaller level on top of a long straight piece of lumber to get the same effect. Backfill any areas that were cut too deep and use a hand tamper to firmly pack them.
It's very important that each layer of your patio be level. Any shallow spots can cause water to pool, creating puddles or, in the winter, ice patches. The next step is to add base material, usually crushed stone or gravel.
Unlike soil, stone has a uniform hardness and provides efficient drainage. But before you can add that, you need to set up your screeds—straight pieces of lumber set parallel in the hole—about three feet apart. Two by fours positioned on edge work well. Sight down each to make sure that the boards are straight and do not crown, or rise up, in the middle, then check them for level in the hole [3].
If your screeds aren't long enough to span the patio space, or if you don't have enough to cover the entire area at once, work in segments. Set your screeds in the footprint of your patio. Hold them in place by packing base material around their sides, then dump one to two inches of base layer between the screeds. Each layer is called a lift.
Distribute the stone with a base rake, a wide aluminum plate with one smooth and one serrated edge. An ordinary bow rake will also work, but you'll need to rake several passes with the tines down, then flip the rake on its back for a few more passes.
We need to calculate the slope of the actual patio to be able to understand where that patio is going to end with a known starting point at the foundation. The most basic method of measuring this slope and marking it out so you can continue to measure during the construction process would be to use string line.
We will put a post at the foundation of the house where the patio is starting and a post where our patio is going to end. We tie a string line on these posts that represents the top of paver. Start at the foundation where the string will represent the top of the paver and tie the string line to the post at the far end of your patio, put your string line level on that to make sure that it is level, and continue with any other posts that you have to mark your patio. Once our string line is level, we can then measure the distance from the house to the end of the patio.
So we are going to lower that string line at the end of the patio one inch down. That gives you your starting points at the foundation and the ending points at the back of the patio.
Now you can adjust that as you see fit to be able to minimize the amount of steps that you need coming out of the house or to minimize the amount that you need to build up at the end of the patio.
However, you can then put four different pegs for the four different corners of your patio with that slope at the top of string line should represent top of paver so from the top of paver down, you are actually going to be digging the height of the paver which is typically two and three eighths of an inch, the one inch bedding course or a screed layer, and then six to eight inches of base materials what we opt for our paver projects in our business.
Base preparation may vary depending on your location. Where I operate my business, we have multiple freeze-thaw cycles each year. To accommodate that we prepare a minimum of 6 inch base to a maximum of 8 inch base for patios and walkways. For driveways, we prepare a 12 to 14 inches of base. For the depth of our excavation, we need to add the depth of our base, the one inch screed layer, and the height of our paver. We want our excavation to be uniform to match the slope of the top of the patio where the pavers are going to lay so that the slope is going to be consistent.
This keeps water away from the foundation and ensures consistent movement of the base. We want that to be as consistent as possible in our install. If your base is 6 to 8 inches, you are going to excavate 6 to 8 inches past that final paver. What this does is it gives your paver a nice solid platform to sit on that they are not going to start to slide outside of that base material with traffic load on them.
Once our base has been excavated, we are then going to compact our subsoil. This compaction of the subgrade material is incredibly important. It cannot be overlooked. If you have a heavy clay soil where you can roll it up into a ball really firmly, you will opt to use a ramming compactor to be able to compact. This really kneads the clay and gets the clay particles compacted properly. Alternatively, a heavy reversible compactor works for heavy clay materials.
If you have a sandy subsoil, you can get away with a reversible compactor of medium size to compact that subsoil. What we use is a ramming compactor for clay. Projects with sandy soil, we use a medium size reversible plate compactor that has a force of 3, pounds. When it comes to compacting our base material , a good rule of thumb is that one inch of base material compaction requires 1, pounds of force.
If you have a compactor that is only good for 1, pounds of force, you can only compact one inch of material at a time.
The next step is to use a woven or non woven geotextile fabric. When it comes to our projects, we are primarily using a woven geotextile fabric especially for soft subsoils.
It also provides some tensile strengthening of our base to spread out that load over a greater area. This makes sure that any water that gets on it is going away from the foundation and not going underneath another piece of fabric. We can then start with our base preparation. There are a few different base preparation methods to do here. The purpose of an open graded base is that it allows water to filter through it with no resistance.
We use this in every raised patio installation. The final base preparation method would be to use a synthetic base which actually minimizes the amount you would be excavating in your project. You would excavate just for that one inch bedding layer, three quarters of an inch for the synthetic base material, and then your paver at that height which is typically somewhere around four inches depending on the height of your paver.
This can not be used for a driveway installation though there is a driveway installation synthetic base products out on the market that I have not yet used in my business. For walkways and patios, we are typically installing a synthetic base if it is on grade and an open graded base if it is a raised patio. Depending on our compaction equipment available, we are going to do certain lifts of our material.
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