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What Grade is Driveway Gravel?

If you’re about to build a new driveway or resurface an old one, then this article should prove to be very helpful.

Most driveways are constructed with three types of gravel. The base foundation layer is commonly made of four inch deep #3 gravel, the middle drainage layer consists of #57 stones, and the aesthetic top layer can be pea gravel, marble chips, Jersey shore gravel or blackstar rock.

Let’s dive down into the subject of driveway gravel in more detail, and discover the different grades or gravel, what they’re useful for – and how to apply them…

What Grade is Driveway Gravel?

What’s The Best Type of Gravel That Can Be Used For Driveways?

There are various different types of gravel available. How do you know which is the right one for your driveway? Because most driveways are constructed with several layers of gravel, the answer is: you’ll need three types.

The bottom layer is typically made from a four inch deep base of clean stone (also called #3 gravel, and we’ll come onto this in a minute). These stones are usually around 2 inches in diameter, and provide excellent drainage for the base layer. You could also use recycled stones, brick, concrete, and rock for the lowest drainage layer, or a blended aggregate known as “crusher run”.

The middle layer is also good for drainage, and is often constructed from #57 stones (we’ll explain this in a moment, too).

What about the top? This is about aesthetics as well as strength and practicality. Pea gravel is popular as it looks good (these small round stones come in a range of colors). Marble chips are more expensive, but they sparkle attractively in the sunset. Jersey shore gravel is a rich, sandy color which creates a very pleasing effect. 

These surfaces will need containing at the edges to stop them from spreading outwards. Avoid this by using blackstar rock, which locks together, or a more crushed mix which will compact to form a more solid surface.

What Are The Different Grades of Gravel?

As we’ve already mentioned, gravel comes in different grades, and you’ll be pleased to hear that these are standard across the US. The grades relate to sizes; so once you realize that we’re simply talking about different-sized pieces, it all becomes a lot clearer and stops sounding like some sort of builders’ code.

Let’s take a run through the various grades of gravel that are available.

#1. This is the largest grade, and stones can be as big as two to four inches. You’d use this for jobs such as filling in holes.

#3. Number three crushed stone varies from half an inch to two inches in diameter. It’s a good size for drainage.

#5. This grade has pieces measuring one inch or smaller. You may be needing this one, as it makes a good driveway or paver base.

#8. Smaller again, number eight includes stones of between a ⅜ and ½ of an inch in diameter. This is used in concrete mixes.

#10. Now we’re basically talking dust. Indeed, it’s sometimes known as “dust”, and also, “screenings”. It’s used to make concrete blocks and pavers.

And then the grading system goes completely crazy, skips a load of numbers, and arrives at a larger size than #10…

#57. This crushed stone measures around ¾ of an inch. It’s generally used for concrete mixes, drainage, and landscaping.

#67. Between #5 and #8 size-wise, #67 pieces are ¾ of an inch or smaller, and make a good base material for roads and slabs.

There’s also a type of crushed rock called “crusher run”, which is a mix of fine and coarse aggregate. This blend of dust and small stones creates a layer that both compacts and drains well. It’s also cheap to buy.

What is The Cheapest Gravel For a Driveway?

As we were just saying, crusher run (or crush & run) is a cheap option for constructing a driveway. It’s commonly used as a base layer under pavers, patios, pathways, and drives.

If you take a look at these gravel driveway costs, crusher run comes in as the least expensive, as just 40 cents per square foot. It’s cheap and robust, which are both good points. However, it’s not the prettiest option, and you’ll simply get whatever the truck dumps on your lot: you don’t get to specify stone or color.

However, as crusher run is typically used as a base layer, the aesthetics don’t matter so much. What you will get is a sturdy driveway that won’t do too much damage to your budget.

How Deep Should I Make My Driveway Gravel?

A standard driveway is between 12 and 18 inches deep. If that sounds like a lot, remember that you have three layers of gravel (or other aggregate) to get through before you end up with a smooth, finished surface. You’d better get digging.

Each of these gravel layers is a minimum of four inches deep, and some folks recommend making each layer as much as six inches. If you have a large area to dig out for your new driveway, the idea of a shovel and wheelbarrow may not be very appealing at this point. You may choose to hire some sort of excavator, or at least, get some help. You’re shifting earth up to 18 inches deep, for the entire area of your driveway: that’s quite a task. 

As you go along, it’s important to compact a layer before adding the next one: this will make your driveway stronger. You can do this by driving up and down the driveway a few times (just watch out for your tires. You may want to borrow a truck for this).

A good tip is to schedule the delivery of each type of gravel so they don’t all arrive at once. Order your crusher run or #3 first, then allow time for that to be in place before your #57 arrives. Then do the same for whatever you’ve chosen for the final gravel layer (marble chips, pea gravel and so on).

How Much Does a Ton of Gravel Cover?

The answer is it depends on the type of gravel and the depth of the driveway. Generally speaking, it takes 1.4 tons of stone to fill a cubic yard.

The surface area that a ton of gravel will cover depends on what type of gravel you are using, and how deep your driveway will be. Are you going for four, five, or six inch layers? This makes a huge difference to the amount of gravel you will need. Make life easier for yourself with this handy online gravel calculator.

It’s certainly worth doing the math, as over ordering gravel can leave you with piles of excess stones to shift, while under ordering cna stall the project as you pause to source some more.

Gravel driveway

Do I Need Fabric Under My Driveway Gravel?

Adding a layer of landscaping fabric beneath your driveway is a good idea. Not only will it prevent unsightly weeds from spoiling the look of the surface, but it will prevent roots from undermining the structure.

This goes right at the bottom of your newly dug driveway trench. Before you start pouring in the stones, first prepare the earth base. Tamp down the soil, and pull up any weeds. Remove any other debris, such as roots. Then, when you have a nice, solid earth foundation, lay down a layer of membrane. 

This needs to be proper landscaping fabric, otherwise you’re compromising the drainage. You can buy it in rolls on Amazon, and it’s really easy to cut to size. Don’t skimp on quality, as you really won’t be able to replace it once it has three, six-inch layers of gravel on top of it.

Conclusion

So there you have it – to create a new driveway (or resurface an older one), you’ll need three types of gravel around 12-18 inches deep in total – with a fabric layer underneath.

The foundation layer can be made up of #3 gravel, the middle drainage layer #57 stones, and the aesthetic top layer can be pea gravel, marble chips, Jersey shore gravel or blackstar rock.

What you end up having as your top layer is really down to your personal choice of what color you want and which type of gravel/stone chips you most like the look of. 🙂

Mark H.

Homeowner and property investor Mark H. aspires to bring you the very best outdoor living content, based on his years of experience managing outside spaces. Read more >