A loose-brick patio generally consists of a border of weatherized lumber, with a 4-inch-deep underlayment of crushed gravel topped by a 1-inch layer of sand, then topped by bricks. Calculating the correct amount of each of those materials can be tricky. Usually, your best guess will come up short. Spend an hour with a tape measure and calculator before you buy your materials, and it will save you from having to run back out for more supplies in the middle of the project.

- Skill level:
- Moderate

### Other People Are Reading

### Things you need

- Tape measure
- Stakes
- Twine
- Calculator
- Weatherized 2-by-4s
- Weed block (in rolls)
- Standard paving bricks (4 by 8 inches)
- Construction gravel
- Construction sand

Show More

## Instructions

- 1
Measure the area for your patio. Set stakes in the corners. Stretch twine between the stakes.

- 2
Multiply the width times the length of the patio to get the square footage. For example, a 10-foot-by-12-foot area is 120 square feet.

- 3
Calculate the weatherized 2-by-4s you'll need for the perimeter by measuring the length of each side. In this example, you'll need two 12-foot 2-by-4s and two 10-foot 2-by-4s.

- 4
Calculate the amount of weed blocker you'll need by dividing the width of the area by the width of the weed blocker, then multiplying by the length of the area. If the weed blocker is 4 feet wide, you'll need three courses of it, each 12 feet long, to cover the area -- meaning 36 feet of it.

- 5
Calculate the number of 4-inch-by-8-inch bricks needed by multiplying the square footage of the patio area by 4, and then adding 10 per cent. A 120-square-foot patio will need about 528 bricks (120 times 4 equals 480, plus 48 equals 528).

- 6
Calculate the cubic feet of gravel needed by multiplying the number of square feet by .333 (since 4 inches of gravel is one-third of a cubic foot). A 120-square-foot patio will require 39.9 cubic feet of gravel (round it up to the whole number, meaning 40 cubic feet).

- 7
Calculate the cubic feet of sand needed to top the gravel by dividing the cubic feet of gravel by three. (This will give you 1 inch of sand, plus some extra to allow some of it to sift down.) If you need 40 cubic feet of gravel for a 120-square-foot patio, you'll need about 13 cubic feet of sand.