Rain Water Leak Diagnosis

You would be surprised how the water can leak past the door seal, slip under the aluminum strip and work under the flooring then spread through the particle board in the flooring. If you are doing a remodel I recommend pulling every window and replacing the sealing as the factories do a poor job. Also check the bottom of outdoor speakers to ensure they have not rotted out allowing water in. All lights need resealed on the outside just like the windows.

I had the same general damage to the floor in the back corners of my unit. After replacing the flooring when I reinstalled the flooring I caulked the entire back and edges making it water tight on top. I haven't felt any soft flooring since then. I also had every event I spoke of in the first paragraph.

Good luck with your remodel!

fj12ryder wrote:
That looks very much like the damage I had to repair this last summer. My problem was caused by the poor sealing done around the vent flashing on the outside. There was no sealant around the top part of the flashing and water would come in, run down the wall and soak the wood. You couldn't tell a thing was wrong until the floor was gone. No stain, no swelling. The wall below the vent also had to be replaced. That was a real pain.

Thank you for your insights. And for anyone keeping score: I took out an electrical plug in that wall - directly above the damage - to get a look inside that wall. No signs of water in the wall and the insulation was completely dry. Diagnosis continues....

That looks very much like the damage I had to repair this last summer. My problem was caused by the poor sealing done around the vent flashing on the outside. There was no sealant around the top part of the flashing and water would come in, run down the wall and soak the wood. You couldn't tell a thing was wrong until the floor was gone. No stain, no swelling. The wall below the vent also had to be replaced. That was a real pain.

Thank you all! Input much appreciated!

We had damage pretty similar looking and it came in through an aged butyl seal around a hatch door and window. Once the hatch door and window were removed it was obvious they were the culprit of the leak. My husband was in a huffy mood and ripped through the luan board. We were not able to find a matching luan board so we had to paint the entire interior which was fine with me since I didn't like it in the first place. He used a multi dremel tool like this one for cutting out rotten wood. Dremel MM40-05 Multi-Max 3.8-Amp Oscillating Tool Kit with Quick-Lock Accessory Change Interface and 36 Accessories

Two words, Seal Test.

Here's another pic. Not pictured is an aluminum strip I removed prior to photographing that provided a finished edge over the vinyl and the black steel frame of the ramp door. I'm a little curious that water was leaking through the ramp door seal, under that aluminum strip, and then under the vinyl (thereby not visible on top of the vinyl)??