Alright, folks, let's talk about cleaning concrete. I've got this driveway that looked like it had been through a mud-wrestling championship. Seriously, it was nasty. So, I decided to tackle it myself, and the first question was, "how much pressure do I actually need?"

Figuring Out the PSI

First things first, I borrowed a pressure washer from my neighbor, Bob. Thanks, Bob! This thing was a beast, but I had no clue what setting to use. Too little pressure, and I'd be scrubbing all day. Too much, and I might end up with a new, unplanned landscaping project (aka, blasting holes in my concrete).

I did a bit of digging around, asked some folks, and the general idea seemed to be to start low and work my way up. Makes sense, right? You can always add more pressure, but you can't undo etching your initials into the driveway.

The Experiment

I started with the pressure washer on a low setting, probably around 1500 PSI. I held the nozzle a good distance from the concrete, just to be safe. And… nothing. The grime just laughed at me. Okay, time to crank it up a bit.

• Step 1: 1500 PSI - Nope.
• Step 2: 2000 PSI - Getting somewhere, but still needed more oomph.
• Step 3: 2500 PSI - Bingo! This seemed to be the sweet spot.

At 2500 PSI, I could see the dirt and grime just melting away. I moved the nozzle back and forth in a sweeping motion, making sure not to stay in one spot too long. That's key – you don't want to concentrate the pressure and damage the concrete.

The Results

It took a couple of hours, and a few breaks (pressure washing is a workout!), but the driveway finally looked clean. I mean, really clean. Like, I-could-eat-off-it clean (but I won't). I finished the work.

So, based on my little adventure, 2500 PSI seems like a good number for cleaning most concrete surfaces. But remember, every situation is different. Always start low, test a small area, and adjust as needed. And don't forget to wear safety glasses – flying debris is no joke!