Likely Roof Leak

[Bwilliams53]

2018 Grand Design 2600 rb. Up on the Roof last week to pull the cover on. Discovered a very soft spot just forward of the vent housing soft to the touch about the size of a dinner plate. No visible cracks or holes and every year I use the caulking all the way around all the fittings? Must be a leak from the side or possibly the vent going to have to do a spot repair anybody have any experience with cutting the membrane and repairing the plywood underneath?

[howson]

2018 Grand Design 2600 rb. Up on the Roof last week to pull the cover on. Discovered a very soft spot just forward of the vent housing soft to the touch about the size of a dinner plate. No visible cracks or holes and every year I use the caulking all the way around all the fittings? Must be a leak from the side or possibly the vent going to have to do a spot repair anybody have any experience with cutting the membrane and repairing the plywood underneath?

To your specific inquiry (..anybody have any experience with cutting the membrane and repairing the plywood underneath? ) I don't. Based on what I do know and have done, I can make a couple of observations.

1) The soft roof (if caused by water) is a symptom, not the root problem. Fixing the soft spot, while "on the list", is not the primary problem.

2) Cutting the roof material is problematic. If the patch is small enough, a wide band of eternabond tape with lap sealant around all the tape edges might work to hold the roof material in place. (I wouldn't go this route, but if the budget is an issue it might be the only approach? I think I'd cut an "H" and peel back the TPO to expose the paneling underneath, then tape back in place.)

3) Given the age of the unit and the problem at hand, if the plan is to keep the 2600RB for another couple of years consider a FlexArmor roof. They'll strip off all the old stuff, repair as necessary, and when done you'll never have to worry about caulking again. (At least that's what they claim.) My instructor at RVSA (Recreational Vehicle Service Academy) is a hard-nosed, former NY prison guard that pulled no punches when it came to products and services in the RV industry. FlexArmor was the only non-OEM roof he thought was worth the money. https://rvroof.com/

Of course the latter is the most expensive, but it's a "one and done" solution.

Howard

P.S. Welcome to the forum! Hope you'll take the time to fill out your signature line and contribute as time allows. All the info needed is referenced in the Welcome Letter.

[Jlawles2]

I have had to make a repair on my TT slide roof. "H" cut so I could peel back the membrane to fix the plywood under. Eternabond the "H" then lap sealant around the perimeter of the "H".

If you are a DIY guy, CrazySeal is similar to Flex Armor but it's DIY vs taking it in. I did a 25X12 side room at the house. Workout yes and I was running hard b/c I had to replace the tin with plywood. It is direct to deck design.

[Dave27]

I agree with everything howson said about FlexArmor, except the relative cost. We had our roof done over two years ago and it is wonderful not to worry about the roof anymore. We had rotten plywood from a leak around the air conditioner. The cost of the repair was comparable to replacing the plywood and reusing the roof membrane. If the membrane needed to be replaced too, then FlexArmor was a little over half the cost. For us it is not only a superior roof, it was also cost effective.
Dave