flex seal from the inside or eternabond tape

420RVfun,
Update the settings in your profile to "receive private messages". I tried to reply to your private message and couldn't because you selected not to receive private messages.

How do you pm?

There is no advantage to sealing the wall, floor, or ceiling cavities from water infiltration from the inside. The only advantage is stopping air movement in the cavities.

Edit: I replied in your other thread. You can also PM me if you need specific construction advice. I'm a Residential Building Contractor with about 40 years of experience in building trades.

Don't use Flex-steel. It is the biggest rip off going.

I used it on the joints of my aluminum gutters.
I wire brushed them, sanded them and cleaned them with alcohol and in the very first rain storm they all leaked like a sieve.

Jack L

so i had thought of using flex seal on the wood before i install it. Glad to hear someone else thought this way also.

Per flex sealing seams on inside and bubble issue- i am thinking water won't find it's way in and will flow down along the seam and drain out the bottom. i would spray starting at the top and shingle down in layers. i have the entire seam available, no wood at this time. it was all rotten and is going to be replaced.

Thanks for the input. I greatly appreciate it.

No to flex seal. Any moisture under it will cause it to bubble. Once bubbled water seepage will follow.

Eternabond is a proven product. It works. However, it's usually used on the exterior.
Applying it to the interior of the walls will probably work but it may be difficult to roll/seal it properly.

I don't know much about Flex Seal. It would be easy to spray on. How long will it last is the question.

In your application I would try the Flex Seal.
It won't hurt anything and may last a long time. For long term results use Eternabond on the exterior.

Keep us updated on your project.

I've used Flex-Seal on wood, just in case there was some water infiltration. If you're asking which will seal better over the long run, I'd go with Eternabond. Think of it this way: Which would be best to patch a roof leak? No contest. Good luck with a big project!