For a patio it is common to use a #3 bar spaced every 18″-24″ while for a driveway #4 bar is often used with a 12″-18″ spacing. Different projects require a different size rebar and will require the rebar **to be spaced differently.** Most projects require rebar to be laid in a grid pattern with bars running in opposite directions and overlapping.

Another thing we asked ourselves was, how much rebar should I put in my driveway?

For driveways and patios a **#3** rebar which is 3/8 inch in diameter should be sufficient for the purpose. If you are constructing walls, piers or columns I recommend the use of #4 (1/2 inch) rebar. For building footings I would use a #5 (5/8 inch) rebar. The installation of the rebar is critical for the success of the overall project.

Generally, one stick of rebar per 8 inches of footing width will suffice. If your footings are 16 inches wide, you will need to add **two sticks of rebar along the width of the footing**; however, if your footings are 24 inches wide, you will need three sticks.

The total cost for installing rebar is **$1-$1.20** per square foot. This will translate to $500-$600 for a 500 square foot area. The labor for a 500 square foot is averaged at $280-$345. This is equivalent to roughly $62-$76.50 per hour. Other than labor there are materials and supplies that are needed to install rebar reinforcements.

## How to calculate amount of rebar?

Calculate Rebar Quantity From **Total Slab Area and Perimeter** To calculate Total Area of a multi sided slab, first divide the shape into rectangles or squares. (as in example diagram) Multiply the 2 different side lengths of each rectangle to find individual areas, then add them together to find Total Slab Area.

This begs the question “How do you calculate rebar?”

Find out the total length of rebar. **Multiply that length of rebar by the weight per length** associated with the size of rebar that is used. To figure out the total length of rebar in a grid used in a slab, there are several factors: The dimensions of the slab (length, width and depth) The spacing of the rebar. The inset from the edge of the slab before the rebar is used.

How do I estimate the quantity of rebar in slab?

Convert your longitude measurement into inches: 15 feet x 12 inches per foot = 180 inches. Divide your result by the spacing measurement: 180 in / 14 in = 12.87 (round up to 13)Add one rebar to your result: **13 + 1 = 14.**

## How do I choose the best rebar sizes?

There are various factors to be tested that fall into the following categories: **Tensile strength, bending/malleability, compression, and fatigue.**

While we were reading we ran into the question “How big is #4 rebar?”.

There are two different shows each hour with the first show being about 20 minutes long and starting on the hour. The second show is about the same amount of time and starts on the half-hour. **Get local news delivered to your inbox**!

The first letter or symbol means producing mill and deformation pattern. The **second marking** means rebar size, and grade: a., and b. Grade 400R: 400/ One line (at least five deformations long)., and c. Grade 500R: 500/ Two lines (at least five deformations long)., and d.