Start with the shape you have, not the rectangle you wish you had
Stand at the road and look up the drive. Almost nobody has a rectangle. There is a flare where it meets the pavement, a straight run, usually a pinch somewhere along it, and then a wider area in front of the garage where you actually park and turn around. Measuring the middle and calling it done is how people end up a third short.
Break it into pieces that are close to rectangles and measure each piece. The flare, the run, the parking area, the turnaround. Add the square feet together at the end. For a curve or a fan shaped apron, measure the box it would fit inside and take a little off. You are after a planning number here, not a bid, so close is close enough.
How to get feet without a hundred foot tape
A tape is better, but paces work fine. Count your steps down one edge of the drive, then measure ten of those steps against whatever short tape you do have and divide, so you know what your own stride is worth. Do that once and you can pace anything on the property for the rest of your life.
- Measure the width in at least three places. Drives are rarely the same width end to end.
- Measure to where you want concrete, not to where the gravel currently stops.
- Write down whether there is old concrete to come out, and how thick it looks at a broken edge.
- Note any soft or wet spot you already know about. It has to come out and be replaced with stone that takes compaction.
- Note where a loaded truck could sit, and whether it could turn around, then take a couple of phone photos of the slope and the access.
Square feet first, then thickness, then yards
Square footage is what a price is built on. Volume is what gets ordered off the plant. Multiply your square feet by the thickness in feet, so four inches is a third of a foot, divide by 27 for cubic yards, then add about 10 percent for waste. Ready-mix comes out in 10 cubic yard loads and a job rounds up to the next full load, which is why a drive landing just over a boundary can cost more per square foot than one sitting just under it.
You do not have to run that arithmetic yourself. The cost estimator on the homepage does it in about ten seconds and gives you the square feet, the yards, the loads and a range in one pass. Where load boundaries really bite, and what to do about a job that sits right on one, is worked all the way through on our cost pages.
Two drives with the same square footage, two different numbers
This is where the tape stops helping you. Take 960 square feet, a 24 by 40 drive at four inches. At the driveway band of $8 to $12 per square foot installed, that is roughly $7,680 to $11,520. Where inside that spread your own job lands has almost nothing to do with the measuring.
A flat, open drive on firm ground that a loaded truck can back straight into sits low in the band. The same 960 square feet on a grade, over red clay that holds water, with an old slab to break out and haul off, and with the concrete traveling on hose because nothing loaded is getting close to the forms, sits high. Tear out and haul off adds $2 to $3 per square foot by itself. That gap is why we come measure it ourselves before a real number goes on paper, and why the question of what makes two bids differ has a page of its own.