Cleaning roof

You can test it out yourself. Get a ladder and climb up. Then, standing on the ladder press with your hands on the roof. If it has any "give" then, absolutely not. If it does not, you can find spots that are more solid than others. Press around and feel for the joists that run crosswise on your roof. Put hand pressure there and see how solid it is. You can then slowly exert more of your weight on these spots and see how much "give" the roof has. If anything "gives" then you absolutely cannot get on the room. If it still feels solid, then give it a try, slowly adding more weight. You may even try laying flat on the roof on your stomach to distribute your weight over a larger are, then slowly come up on your hands and knees. Now your weight is distributed over 4 points. If it still feels solid, you have no cracking or anything, then find those joists and see if you can add weight to your feet until you are standing. But if anything gives, then stop.

OK, now that you know you "might" be able to walk on your roof, don't! If you need to get up there to fix something, stay on all 4'x or on your belly laying down. Better yet, do it from a ladder. It's just much safer than standing.

My current trailer has a walk-able roof. But I do everything from a ladder. If I need to inspect the calking around one of the roof vents, I lay down and crawl over to it. Standing is just really unsafe.