Re: boarding ladder ideas 25 ft boat (Irwin 25)
Our Catalina 25 had a ladder that was offset to one side of the transom and which folded down. It worked well and could be deployed from the water, which is a good safety feature.
You can buy the same ladder from Catalina Direct. It looks like this could easily be retrofit to an Irwin 25. They include the hinge/mounting brackets with the ladder.
I couldn't find other ladders for our Catalina 25 with the same properties of being able to be deployed from the water, folding up nicely out of the way when not in use, and staying attached to the transom.
1986 Pearson 28-2 "Elena"