It happens at the A Class Building Materials counter most weeks. Someone picks up two impact drivers from the same brand, same voltage, same battery. One is noticeably dearer than the other, and the only real difference on the box is a single word: brushless.

The honest answer is that brushless is better. But "better" and "worth it for you" aren't the same question. Here's how we talk it through with the tradies and DIYers who come through Ravenhall and Diggers Rest.

What's actually different inside

A brushed motor spins because two small carbon blocks, the brushes, press against a rotating commutator and physically feed current into the armature. It's simple, it's been around for over a century, and it's cheap to build. It also means two components are grinding against each other every second the tool runs.

That contact costs you three things: friction (wasted energy as heat), wear (brushes are a consumable, and when they go, the tool stops), and carbon dust inside the housing.

A brushless motor deletes the brushes entirely. An electronic controller energises the coils in sequence and senses where the rotor is, so timing is managed by a circuit board instead of by physical contact. Nothing rubs. Less heat, no wear part, and the tool can read what's happening under load.

The three benefits you'll actually notice

More work per battery. Because you're not burning energy as friction, more of the charge reaches the chuck. Depending on the tool and the task, that's typically somewhere in the range of 20 to 50% more work per charge. On a framing day where you're driving screws all afternoon, that can be the difference between two batteries and four.

The tool thinks. This is the underrated one. A brushless tool's controller adjusts power to the load. Drilling pilot holes in pine, it sips. Hitting a 100mm batten screw into hardwood, it ramps up. Brushed tools run flat out regardless, which is why they bog down and get hot on the jobs that matter most.

It lasts longer. No brushes to replace, less heat to cook the windings, and generally a better sealed motor. On a tool that gets used every day, that's the argument that wins.

There's a fourth, quieter benefit: size. Brushless motors are more compact for the same output, which is why the modern brushless impact driver fits places the old one physically couldn't.

Where brushed still makes sense

We'd be doing you a disservice if we said "always buy brushless." Plenty of times we'll point someone at the cheaper tool.

• Occasional use. If a tool comes out of the ute a few times a month, you'll never wear out a set of brushes. The premium buys you nothing you'll feel.

• Corded tools. The runtime argument evaporates when you're plugged into a 10 amp outlet. A corded brushed grinder or drill is still perfectly good gear.

• Tools that get flogged or go missing. Site grinders, demo tools, anything that lives in a shared trailer. Buy cheap, expect to replace it, don't cry when it walks.

• A first tool while you find your feet. An apprentice still working out whether they're a chippy or a concreter shouldn't commit to a top tier platform yet.

The maths, done properly

The rough rule we use: weigh the premium against how many hours a week the tool actually runs.

A brushless upgrade on a drill you use for two hours a week is an expensive way to buy very little. The same upgrade on a circular saw running three hours a day pays for itself well inside the first year. You'll see it in batteries you didn't have to buy, time you didn't spend waiting on a charger, and a tool that's still going strong in year four while the cheap one is on its second set of brushes.

There's also a resale angle: brushless tools hold value noticeably better secondhand.

Tool by tool: where the upgrade earns its keep

Worth it, almost always:

• Impact driver. The highest use tool most trades own, so the biggest cumulative gain.

• Circular saw. Brushed cordless saws bog in wet hardwood. Brushless doesn't.

• Rotary hammer or SDS. Heat kills brushed motors here faster than anywhere else.

• Angle grinder. Brushless models hold speed under load, which matters for cut quality.

Marginal:

• Drill/driver. Nice, but most drilling is light work. Fine either way if it's your second tool.

• Reciprocating saw. The blade is usually the limiting factor, not the motor.

Don't bother:

• Orbital sander, heat gun, glue gun, corded anything. Low load, low duty cycle, or mains powered. The premium doesn't come back.

The thing that matters more than the motor

Choose your battery platform first. Motor type is a decision you make once per tool. Platform is a decision you live with for a decade, and once you own five batteries and three chargers in one brand, switching costs real money.

Before you commit, check the platform has the tools you'll want in three years, not just today. And buy at least one high capacity pack (5.0Ah or above) for the saws and grinders. A 2.0Ah pack on a brushless circular saw wastes the motor you just paid for.

One more consideration for Victorian sites

Dust. Between concrete cutting, silica controls and the state of a framing deck in February, motor sealing matters. Brushless housings don't need airflow past a brush assembly the same way, and most brands seal them better as a result. That's a genuine longevity argument on top of everything else.

Our take at the counter

If it's a tool you'll hold most days, go brushless with no hesitation. If it's a tool that lives in the back of the Ute for that one job a quarter, save the money and spend it on better blades and bits, which will do more for your finish than any motor will.

Come and pick both up. Weight and balance in your hand tell you more than the spec sheet, and the A Class Building Materials team at Ravenhall, Diggers Rest and Geelong will give you a straight answer either way, including "you don't need that one."

Got a trade account with us? Ask about setting one up next time you're in. It makes kitting out a new apprentice a lot less painful.