We're replacing the flooring in our coach and knew that that first step into the coach didn't feel right...now we know why!
I'll have to check my coach out tomorrow that don't look good water can I got lot ta damage quickly
Remember this is 20 years...and as I've said many times here...we'll never spend what a new coach of lesser quality costs new. We're happy to spend money on our Foretravel. Notice I said "spent" NOT invested.
Ours was not as bad as your photos, but not too far off. I noticed it when my wife stepped into the coach. I could see the step give, but didn't notice when I stepped on it.
It was pretty easy to remove the rotted wood, and build it back up with 2x4 sections, and some plywood. I was able to clean and reuse the original step covering. Then I caulked all of the edges, so water can no longer go down into the step.
I think of it as "My Hobby". Dulls the $$ pain...
Suffice to say that this post shows another case of owners not looking at the possible areas for problems and doing sonething about it.
The doors hinge area and spray from wheel behind the entrance door have to be sealed to keep that bottom step dry. About twice a year the foam insulation on sidewall in front of tyre is sprayed with a bitumin spray can and thus will prevent water from wicking thru foam. I also added a bottom wiper to inside the door so any water will be "wiped" off the step when door is opened. My steps are as solid as new and all it takes is a few minutes a couple of times a year to look after.
Along with 6 months checkup of all screws in trims (if your coach has these) and looking closely at roof surface etc you will remove all these screwups from happening.
This, and making sure there are no leaks in lower bays, and that they are as clean as original will not only save money later but keep a coach in almost as new condition.
JohnH
My bottom step looks about the same as the OP, but my leak is from the top right corner of the door frame. When it rains hard, water falls from the roof gutter right on top of the entry door frame and gets in behind the frame and runs down to the bottom step area. Haven't taken the door out yet to remedy, but another area to look at as a possible entry.
To stop that one just put a line of clear caulking extended from both edges of gutter above door so it directs water away from door frame and harmlessly down either side of it. I forgot to mention that fix as I did it so many years ago for same reason. It was supposed to be a temporary fix but has worked so well over the years I forgot about it.
JohnH