I have been using the thick rubber interlocking Gym matts which are fairly cheep and easy to trim to fit but after a year or so the material breaks down and tiny pieces of black rubber go everywhere and it leaves black marks. Aside from getting a custom cut SeaDek interested in what u use to protect your floor.
I posted about this in October 2024. I'd give you the link but I can't figure out how to do that. Boomer problems.
Anyhoo, the stuff I use is called Deckadence, you can see it here:
https://marineflooring.net/gallery/ (and yes, that loads slowly). My 228 is the 10th picture there (but it will change as they add more).
If you want something you leave in your boat indefinitely, this is not the stuff. Mine is two pieces, a T at the helm and a big piece that covers the whole cock pit. I take them out and wash them after each trip. If you leave them outside face up bits of grass/leaves/whatever get caught in them. I tend to roll them up and stuff them in my garage for winter no fishing times, leave them outside upside down for shorter periods.
If you can handle all of that, then this stuff is AWESOME. I have bad feet, this is like cushy carpet under your feet. People said they will get full of fish guts etc, that's true but it washes right out. I did build a 2x4 washing station with fencing on top. I wash them upside down with just a garden hose (pressure washer is too much, it breaks down the plastic) and then wash them right side up.
I made a mistake buying them in black, it shows too much leaves/grass. If I had gotten a more neutral color, like brown or tan, I could be more lazy about keeping them clean.