A concrete patio takes four to six weeks from digging to walking on it

Building a concrete patio yourself is possible if you have a few weekends, basic tools, and patience with the weather. The work breaks into five phases: preparing the ground, building the frame, pouring the concrete, finishing the surface, and letting it cure. Most of the time is waiting—concrete needs to set for at least seven days before you can walk on it, and longer before it's fully hard.

The actual labor is straightforward: dig a shallow hole, build a wooden border, mix or order concrete, spread it level, smooth the top, and protect it from rain and foot traffic while it dries. The biggest variables are the size of your patio, whether you mix concrete by hand or have it delivered, and your local soil and weather. A small patio (10 by 12 feet) can be a weekend project for one person. A large one or one in clay soil will take longer and may need a second pair of hands.

Key Takeaways

  • Concrete patios need a level base and a wooden frame (called a form) to hold the concrete while it sets.
  • You can mix concrete in a wheelbarrow for small patios or order ready-mix concrete delivered by truck for larger ones.
  • The concrete must cure for at least seven days before you walk on it, and rain during the first 24 hours can damage the surface.
  • Slope the patio slightly (about 1/8 inch per foot) away from your house so water drains instead of pooling.
  • Concrete cracks as it dries; control cracks by cutting shallow lines (called joints) every 4 to 6 feet while the concrete is still soft.

Measure your space and check for underground utilities

Before you dig, call 811 or your local utility locating service. They will mark the location of buried gas, electric, water, and sewer lines at no cost. This takes three to five business days, so call early. Do not skip this step—hitting a gas line or electrical conduit can be fatal.

Measure the length and width of the area where you want the patio. Mark the corners with spray paint or chalk. Check that the ground is reasonably level by laying a long straight board across it and placing a level on top. If one side is more than a few inches higher than the other, you will need to dig out the high side or fill the low side. A slight slope is actually what you want—about 1/8 inch per foot, sloping away from your house—so water runs off instead of pooling.

Dig out the base and compact the soil

Concrete patios sit on a base layer of gravel or crushed stone, usually 4 inches deep. This base lets water drain away instead of sitting under the concrete and weakening it. Dig out the marked area to a depth of about 4 inches (or 5 inches if your soil is clay or very soft). Pile the dirt to the side—you may need it later to fill low spots.

Spread 4 inches of gravel or crushed stone over the dug-out area and compact it firmly. You can rent a plate compactor (a flat vibrating machine) from a tool rental shop for about $40 to $60 per day, or you can tamp it down by hand with a hand tamper (a heavy flat tool on a handle). The goal is a firm, level base that does not shift when you step on it. If you press your foot into the compacted gravel and it sinks more than a quarter inch, it needs more compacting.

Build the wooden frame and set it level

The wooden frame, called a form, holds the concrete in place while it sets. Use 2-by-4 lumber (which is actually 1.5 inches thick and 3.5 inches wide). Cut the boards to length and lay them around the perimeter of your marked area, forming a rectangle or square. Nail or screw the corners together with 3-inch nails or screws, two fasteners per corner.

Set the form level using a 4-foot level. Place the level on top of the boards and adjust them up or down by adding or removing gravel underneath until the bubble is centered. Remember: you want a slight slope away from your house, so the side closest to the house can be slightly higher than the far side—about 1/8 inch per foot of distance. If your patio is 12 feet deep, the far edge should be about 1.5 inches lower than the near edge. Use shims (thin wedges) under the form boards to fine-tune the slope.

Drive wooden stakes into the ground on the outside of the form boards, one every 3 to 4 feet, and nail the form to the stakes. This keeps the form from shifting when you pour the concrete.

Mix or order concrete and pour it into the form

For a patio smaller than about 80 square feet, you can mix concrete by hand in a wheelbarrow or rent a concrete mixer. Concrete mix comes in bags (usually 60 or 80 pounds) at any hardware store. Follow the bag's instructions for water ratio—too much water makes weak concrete, too little makes it hard to spread.

For larger patios, order ready-mix concrete from a concrete supplier. A truck delivers it wet and ready to pour. You will need to know the square footage of your patio and the thickness (usually 4 inches). The supplier will tell you how many cubic yards to order. Have helpers on hand when the truck arrives—you have a limited time window (usually one to two hours) to pour and spread the concrete before it starts to harden.

Pour the concrete into the form, starting at one corner and working toward the opposite corner. Spread it with a shovel so it fills all the corners and gaps. Tap the sides of the form with a rubber mallet to release air bubbles trapped in the concrete.

Level and smooth the concrete surface

Once the form is full, use a straight board (called a screed board) to level the concrete. Lay a 2-by-4 or 2-by-6 board across the top of the form and drag it toward you, using a sawing motion. This removes excess concrete and leaves the surface level with the top of the form. You may need to do this in sections if your patio is large.

After screeding, the surface will be rough. Smooth it with a concrete float (a flat tool with a handle, available at any hardware store for $10 to $20). Push the float in overlapping strokes across the surface. This brings a thin layer of cement paste to the top and fills small voids. If you want a non-slip surface, stop here. If you want a smoother finish, wait 30 minutes to an hour (until the concrete is firmer but still workable) and float it again.

Cut control joints while the concrete is soft

Concrete shrinks as it dries and will crack. You cannot prevent the cracks, but you can control where they happen by cutting shallow lines called control joints into the surface while the concrete is still soft. These joints guide cracks to break along the lines instead of randomly across the patio.

Cut joints every 4 to 6 feet in a grid pattern, running both directions across the patio. Use a concrete jointer tool (a tool with a V-shaped blade, about $15 to $30) or a brickset chisel and a hammer. Press the tool into the surface and drag it in a straight line. The joint should be about 1/4 inch wide and 1/4 to 1/2 inch deep. A chalk line snapped across the concrete beforehand will help you keep the joints straight.

Protect the concrete while it cures

Concrete cures (hardens) over time. It reaches about 70 percent strength in seven days and full strength in 28 days. During the first 24 hours, rain can damage the surface by washing away the cement paste or creating pits. Cover the patio with plastic sheeting if rain is forecast, and weight down the edges so wind does not blow it away.

Do not walk on the patio for at least seven days. Do not park a car on it for at least 28 days. If you need to remove the wooden form, you can do so after three days, but leave the patio uncovered and undisturbed for the full seven-day minimum before using it.

In hot, dry weather, the concrete can dry too fast and crack. If temperatures are above 85 degrees Fahrenheit, mist the patio lightly with water once or twice a day for the first few days. Do not soak it—just keep it slightly damp.

Frequently Asked Questions

Can I pour concrete in cold weather?

Concrete can be poured when the temperature is above 50 degrees Fahrenheit, but it cures more slowly in cold weather. Below 40 degrees, concrete does not cure properly and may be weak or damaged by freeze-thaw cycles. If you must pour in cold weather, use concrete additives designed for cold weather and cover the patio with insulation blankets to keep it warm while it cures.

What if I make a mistake while pouring?

If the concrete is still wet, you can smooth out small mistakes with a float or trowel. If it has started to set (usually within an hour or two), you cannot fix it without breaking it out and starting over. This is why having a helper is useful—you can work faster and catch problems early.

Do I need a permit to build a patio?

Most cities do not require a permit for a straightforward concrete patio, but some do. Call your local building department before you start. If a permit is needed, the cost is usually small (under $50) and the process is quick. A permit inspector may check that the patio is not too close to property lines or utilities.

How thick should the concrete be?

A patio that will only be walked on should be 4 inches thick. If you plan to park a car on it occasionally, make it 5 or 6 inches thick. Thicker concrete is stronger but uses more material and costs more.

Can I stain or seal a concrete patio?

Yes, but wait at least 28 days after pouring before sealing. Sealer protects the concrete from stains and water damage and can darken the color or add a slight sheen. Stain can be applied at the same time. Both are optional—unsealed concrete is durable and will last for decades, though it may develop stains and discoloration over time.