When we bought Kanga (the RV), we knew it had suffered from some water issues in the past, as evidenced by the delaminating walls in some places and the peeling wallpaper in others. The previous owner told us that the problems had been fixed, and the RV was again watertight. Well, as to be expected, that wasn’t the case and when the rains of fall moved in recently, I saw a nice puddle on the floor directly under the dining window.
I felt the wall and could feel the moisture in the paneling, so I knew it wasn’t just leaking in through the window, but it was leaking inside of the walls. I don’t think theres any serious structural damage to the wall because when I hit it, everything seems good and solid, although I’ll probably at least cut a hole in the wall sometime in the spring to make sure all the woodwork is solid and not rotted.
All of that lead up to me trying to figure out where the water was coming from. The design of the window allows water to drain out of the channels to the outside of the window casing, so I seriously doubt that water is just running underneath the window glass, which leads me to believe that water is getting in from the top and/or the sides of the window casing itself. I got up on a ladder and examined the condition of the caulking and discovered that it was cracked and had peeled away from the RV body in some places, which would easily allow rain water to seep into the wall behind the casing.
Time to re-caulk the window.
Firstly I removed most of the old caulk using a utility knife and my fingernails. In the past, someone had done a pretty good job caulking this window, but it just failed with age and sun damage. The caulk came away with about 20 minutes of work and left me with a pretty clean surface to work with. I also removed the old caulk along both sides and the bottom corners of the window casing just in case water was running along the edge of the window and getting in that way.
When I was happy with the amount of old caulk I had removed, I used some Windex to clean up the casing and the fiberglass RV body. While I was at it, I went around and cleaned all the windows in the RV because they were pretty gross, to be honest.
Using 100% silicone caulk, I laid down a nice fat bead all around the window casing.
Now, some people use a special tool to flatten out caulking, but I like to use my finger because it allows me to control how much caulk I lay down in areas. Its also kinda fun! Like finger painting.
I made sure that there were no breaks or gaps in the caulk when I was finished, and figure this is a finished problem. It isn’t perfectly smooth because there were little bits of old caulk still attached to the RV, but it doesn’t matter and would have required way more time to remove every tiny scrap of caulk than I wanted to spend. In the end, it doesn’t matter because the new silicone caulk is unbroken and the unevenness of the job is hidden above the window, out of view.
Now that I did this window, I know that all the other ones need the same job done. The caulk on the bathroom window is complete garbage, and so are other ones.