Now that you have decided to sealcoat your driveway, you need to know how to estimate your material usage before you order the product.
Before I go into details, I need to give you a disclaimer. In no way is this a 100% guarantee on coverage rates. Coverage rates will vary from job to job, and is dependant on many different factors.
Here are those common factors so you can keep them in mind.
Has your driveway been sealed before?
If it has, your material coverage will improve slightly. If it has not, you will use more material. The increased material usage is due to the driveway sealer filling any voids from the paving process.
How many cracks in your driveway?
By this, I do not mean small “spider web” cracks (although they will use some extra sealer). I refer to the bigger cracks. Sealing your driveway without filling the cracks can use extra sealer, unless you take measures to avoid letting the driveway sealer fall into the crack (or if you believe the driveway sealer will act as a proper crack sealer). Proper crack filling will help reduce material usage.
How is the surface?
If it is very smooth, it will use a lot less sealer (and if it is really slick, you probably do not need to seal). If it is very rough, it will use more.
The baseline formula is as follows:
Figure your square footage (Length X Width). Divide that number by 9 to come up with your square yardage (round this number up to the next whole number). Multiply your square yardage by .17 (17%).
In most cases that number will get you relativly close. If you have doubts, buy one 5 gallon pail more than needed (but check out the return policy beforehand.) Any extra sealer can be saved and used to touch up spots, or maybe give a second coat to areas prone to oil drips. Just remember that you need to keep driveway sealer from freezing if you save it to touch up spots later.
I will give you an example. Lets assume you have a driveway that is 50 foot long, and 20 foot wide. Your square footage is 50 x 20, or 1000 square feet. Divide 1000 feet by 9, which gives us 111.11 square yards. We round that up to 112 yards and multiply that by .17. We come up with 19.04 gallons of sealer, so we order 4 buckets.
This number is not absolute, but it will get you reasonably close for one coat. If you double coat your driveway you can expect a 10-15% coverage rate (multiply your square yards by .1 to .15) on your second coat.