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A standard concrete patio should be 4 inches thick for foot traffic only. For areas that will support light vehicles or heavy furniture, increase thickness to 5-6 inches. Always pour over a compacted gravel base of 4-6 inches for proper drainage and stability.

Multiply length (ft) x width (ft) x depth (ft), then divide by 27 to convert cubic feet to cubic yards. For example, a 12x12 foot area at 4 inches (0.33 ft) deep equals 12 x 12 x 0.33 / 27 = 1.76 cubic yards.

Concrete reaches about 70% of its strength in 7 days and full strength in 28 days. You can walk on it after 24-48 hours, drive on it after 7 days, but avoid heavy loads for at least 28 days. Keep it moist during the first week for optimal curing.

Cement is just one ingredient in concrete. Concrete is made by mixing cement (the binding agent) with water, sand (fine aggregate), and gravel or crushed stone (coarse aggregate). Cement typically makes up 10-15% of the concrete mix by volume.

Ready-mix concrete typically costs $120-$150 per cubic yard for delivery, depending on your location and mix type. Bagged concrete costs more per yard but is practical for small projects. For slabs larger than 1 cubic yard, delivery is usually more economical.

Concrete can be poured in cold weather but requires precautions. Below 50 degrees F, concrete sets slower. Below 40 degrees F, you need heated enclosures or insulating blankets. Never pour on frozen ground, and use hot water in the mix to maintain temperature.