Last Updated on December 14, 2020 by Dave Farquhar
Drills and impact drivers look a lot alike, but they’re really different tools for different purposes. One of them is an absolute must-have, while the other is, for most people, a nice-to-have. Let’s take a look at a drill vs impact driver.
Drills are for drilling holes and driving in small fasteners. Impact drivers, which are more powerful and tend to cost more, are for driving in large fasteners.
Do I need a drill or an impact driver?
A bog standard drill is arguably the one tool you want if you can only afford one power tool. I was working on a house with a buddy one day and somehow we both forgot to bring a drill, though we both brought just about everything else imaginable. We were dead in the water until I ran home to grab a drill.
Drills are the best tool there is for drilling holes. And they’re never anything worse than a second choice for driving in fasteners. They aren’t glamorous, but I finished a lot of projects in my younger days with just a drill, a hand saw, a hammer, and a screwdriver.
Depending on the project, an impact driver is very nice to have. I can probably drive screws with an impact driver 2-3 times as fast as I can with an ordinary drill. But there are other tools that belong higher up on your must-have list than an impact driver. A circular saw certainly deserves to be higher. Arguably a reciprocating saw does too. Even after I realized I wanted an impact driver, I got by without one for a few years before finally getting one. I was working on a project, and my brand of impact driver was on sale, so I finally got one. I was even able to get brushless, which I recommend.
Can you use an impact driver as a drill?
You can use an impact driver as a drill, but there are some caveats. An impact driver will only take hex-head bits. The bit you need may or may not be available in that form, and likely is more expensive in that form. Also, because of the stress it puts on the bit, you need drill bits rated for use with an impact driver. Those also cost more. If you accidentally grab a bit that isn’t impact-rated and use it, you’re likely to break it.
With a boring old bog standard drill, I can use a wider variety of bits, and I have more finesse. Over the years I’ve built up a nice collection of bits, including some self-centering bits, left-handed bits for removing broken screws, and specialty bits that are sized perfectly for specific-sized screws. They work fine in a drill. They won’t work in an impact driver.
You also don’t have the adjustments or the clutch that you have on a drill. If you want the to stop turning once you reach a certain depth, use the drill.
Frankly I’d recommend using a drill instead of an impact driver rather than the other way around, if you can only afford one. With a heavy battery you can drive reasonable-sized screws without a pilot hole with a regular drill.
When to use an impact driver
Impact drivers are designed and engineered to drive fasteners, especially large ones, as quickly and easily as possible and without drilling pilot holes. When you’re driving fasteners larger than about a #8-size screw, you’ll appreciate the impact driver’s power versus that of a regular drill. Even with common screws, if you’re using a lot of them in your project, the impact driver will help you get that job done faster.
I once bought a house that had a structural issue. Two of its floor joists had huge notches cut in them. The home inspector knew exactly how to fix it, and told me exactly what to buy. We had to sister new joists to the existing ones to return them to their former strength. But he was very specific about the size of screws to use to sister them. A regular drill wouldn’t drive those screws. We had to use an impact driver for that.
When building storage shelves for my garage, I appreciated having an impact driver. I bought a box of #8 construction screws and used nearly the whole box. I could have built the unit with a regular drill. Indeed, I’ve built things that size with just a regular drill before. But having the impact driver helped me get it done two hours faster and it didn’t wear me out as much. That freed up some hours to put stuff on those shelves.
What to do if your impact driver seems gutless
If you get an impact driver, especially an inexpensive one without a battery, and find you can’t drive screws with it without a pilot hole and wonder why it’s any better than a regular drill, I probably know why. If you’re using a small battery, something smaller than 2 amp-hour, the impact driver doesn’t have enough electricity to run at 100%. And when I run both of them with a 1.3 amp-hour battery, I honestly can’t see a ton of difference between them.
To get maximum power out of an impact driver, get a large 4- or 5-amp hour battery. You’ll notice a difference then. Your drill will appreciate the heavier battery too, but they really make the impact driver come into its own.
At the home centers I see a lot of impact drivers, even the expensive premium brands, bundled with 1.3 Ah batteries. That makes them look like a good deal but it cripples their performance. Unless you have another use for the batteries, you’re better off skipping the bundle, buying the bare tool, and buying one or two big 4- or 5 Ah batteries to go with it. But now you’re talking a $200 or $300 purchase rather than a $140 purchase.
When to use your drill instead of your impact driver
There are times when you need finesse, not power. When installing a door, I once broke one the screws that adjust the height of the threshold by turning it with an impact driver instead of a regular drill. The adjustment screws just weren’t designed for the force of an impact driver, and one of them broke.
When assembling furniture, I’d definitely want something less forceful than an impact driver. I’m thinking of Ikea furniture but also anything that comes in a box.
Frankly, for those types of jobs I like to use my $18 Black and Decker electric screwdriver rather than a drill, because those are designed to turn screws slowly. I drill my pilot hole with my drill if the furniture didn’t come with pilot holes, then drive the screw with the cordless screwdriver. But if you don’t have one of those, use your drill on its lowest setting.
If the screw isn’t going into something that’s going to put up a fight, use something gentler than an impact driver. I wouldn’t think of using an impact driver on plastic or metal with threaded holes. That’s not a good use case for a drill either, but it’s even worse for an impact driver.
And when you’re just drilling holes, a regular drill makes a better drill than an impact driver does. I can use whatever drill bits I want, including the cheap non-hex bits.
Are impact drivers worth it?
I like my impact driver and don’t regret buying it. But I certainly don’t use it as much as my drill. And on small projects, I’m just as happy using my drill if it’s within reach and the impact driver isn’t.
Now that I know the trick of using the biggest, baddest battery I can find in my regular drill, I might need my impact driver less. So if you’re on the fence, get a heavier battery for your drill first and see how that does. You’ll need the battery for the impact driver anyway if you decide to get one.
And I got by 20 years without an impact driver. I got a surprising amount of work done with just a cordless drill and a circular saw, including renovating two houses. Now, I did get to a point where I needed more tools than that, but I bought additional saws and a brad nailer before I bought the impact driver. I needed those a whole lot more, and I still use those tools quite a bit more.
If you’re young and don’t have a lot of money, get a regular drill and a circular saw first. Beyond that, it really depends on the projects you’re doing. If you’re building a shed or storage shelves and you don’t have an impact driver and can afford one, then sure, it will save you a non-trivial amount of time. It will cut the time you spend driving screws by half or even two thirds. You’ll have to decide if that’s worth the cost of the tool and the battery you need to take full advantage of that tool.
If that scares you off, don’t fret. You can compensate. If you have a powerful battery and use hex-head thread cutting screws, you can get surprisingly good results with a boring old drill. The hex head keeps you from stripping the head, and the thread cutting action makes it easier to drill into your work.