Sealing the walls and ceiling

[Miriam C.]

Thin the floor poly some so that it soaks in good.

...yep, thin it 10 to 15% with whatever thinner is applicable and put on 2-3 coats...........................

Doesn't say what to thin it with. It is water based pollyurathane if anyone knows.

Woodbutcher
If I understand it right we should seal all surfaces to keep out the moisture and keep the skins from warping. Seems the moisture can get into the unpainted side and reke havoc.

Hope you had a good weekend.
Aunti M

[madjack]

Well Auntie M, if it is water based, then I guess just thin it with ...........water .....................................

[Juneaudave]

Auntie M...I thought I would share a pic or three on the importance of multiple coats of sealer. Often, builders slap on a single coat of thinned varnish or something and think they have sealed a surface...

So...I'm getting ready to seal a piece of boat trim with epoxy, got my first coat on and I'm happy except for the mess my garage is in....



The first coat of epoxy looks great...life is fine



I put on another coat next day...but a hour later, I get bubbles




On the second coat, the trim was exposed to a halogen light and experienced outgassing where the warmed up wood "breathed" out air. The halogen light was there on the first coat too. It's not the finish heating up (the epoxy gets thinner in heat), its actually the wood "breathing" and the second coat trapped the heated air. Since then, I have only been able to conclude that a single coat of finish does not seal the wood, but rather still allows it to "breathe" (and suck moisture in), the second and third coats seal the surface...Juneaudave

[kayakrguy]

On the second coat, the trim was exposed to a halogen light and experienced outgassing where the warmed up wood "breathed" out air. The halogen light was there on the first coat too. It's not the finish heating up (the epoxy gets thinner in heat), its actually the wood "breathing" and the second coat trapped the heated air. Since then, I have only been able to conclude that a single coat of finish does not seal the wood, but rather still allows it to "breathe" (and suck moisture in), the second and third coats seal the surface...Juneaudave

JD,

I think there is another interpretation of the bubbles. First, yes, the halogen forces air out of the wood. Your first coat of varnish was thin enough for the air to escape--the varnish was heated, therefore thin, air escaped.

First coat of varnish dried. Second coat of varnish on. Halogen on. Heat causes wood to give up air moisture. Dried first coat of varnish traps moisture/air. I think your first and second coats would be fine IF the halogen were not there to heat up the wood.

If the second coat had dried without the halogen present, I doubt you would have bubbles and I doubt that in the future you would have problems because the dried TWO coats would protect the wood from external HEAT and Moisture...

Just a thought...

Jim

[PaulC]

Okay, so now I pull number2 apart to seal the insides of my walls and floor. I think not!! I've have been almost anal in my attempt to ensure no moisture problems and this thread pops up and tells me I'm a goose. Guess I'll just have to go with what I've done and make sure that I do it on Number3. Oh my gawd!!!!!!!---------------- The handbrake will kill me if she reads this

Cheers
Paul

[madjack]

well Paul, you will just haveta bite the bullet and pullit all apart ....adequate ventilation and a dry clime will help a lot
madjack

[Miriam C.]

Well Paul,
There's something to be said for being slow. I'm gonna seal all parts still open.

BTW-how does that effect the glue?

Aunti M

[madjack]

...Auntie M, due to considerations of "glue" we used Gorilla glue to join any already sealed parts...any poly based adhesive should be fine...such as PL construction adhesives...as far as we can tell this has worked just fine.
madjack

[Juneaudave]

I think the bubble thing is a result of rising temps...you should always have your wood and finish up to temp prior to finishing. Especially with epoxy...and let the temp drop as it is curing so that outgassing doesn't occur.

Kind of the same thing with painting a house...don't paint in the morning when temps are rising and dew is on the house, paint after the moisture has burned off and the surfaces will be in the shade and cooling. You'll get a much better job.

[rampage]

Okay, so now I pull number2 apart to seal the insides of my walls and floor. I think not!! I've have been almost anal in my attempt to ensure no moisture problems and this thread pops up and tells me I'm a goose. Guess I'll just have to go with what I've done and make sure that I do it on Number3. Oh my gawd!!!!!!!---------------- The handbrake will kill me if she reads this

Cheers
Paul

I was wondering when someone was gonna say that they didnt do this. From what I can tell by looking at everyones gallery that not many people sealed the insides.
This thread came around just in time for me. I'm gonna seal the insides just to be safe but I doubt its justification. I've never seen anyone paint the inside of the exterior of a house.

[Miriam C.]

...Auntie M, due to considerations of "glue" we used Gorilla glue to join any already sealed parts...any poly based adhesive should be fine...such as PL construction adhesives...as far as we can tell this has worked just fine.
madjack

I put the floor finish on two boards, let it dry and glued it with PL Prem. construction adhesive and it stuck as well as unsealed. I don't know how that will work with paint since the poly soaked in and is satin finish.

btw- PL plus has a vapor odor that doesn't go away, wouldn't suggest using it.

Aunti M

[Miriam C.]

Okay, so now I pull number2 apart to seal the insides of my walls and floor. I think not!! I've have been almost anal in my attempt to ensure no moisture problems and this thread pops up and tells me I'm a goose. Guess I'll just have to go with what I've done and make sure that I do it on Number3. Oh my gawd!!!!!!!---------------- The handbrake will kill me if she reads this

Cheers
Paul

I was wondering when someone was gonna say that they didnt do this. From what I can tell by looking at everyones gallery that not many people sealed the insides.
This thread came around just in time for me. I'm gonna seal the insides just to be safe but I doubt its justification. I've never seen anyone paint the inside of the exterior of a house.

Paul, better make it just for her, her way.

Rampage, ever look at siding these days. It is primed on both sides. Some you don't even have to get around to painting for 30 years. Even OSB has a waterproof coating on the "inside" down side.

Besides what else can I do when it's hot and I can't lift my sides in place alone.

[AmyH]

I am sooooo confused now! All the plans that I have looked at don't talk about this. In fact they usually say to keep the side of the floor uncoated, so you can glue the sides to it. I have already covered the underside of the floor with asphalt emulsion, but I left the side edges uncoated. Should I go back and coat it with something? I sort of figured the PL adhesive would help seal it up when I glue the sides to it.

Amy

[Juneaudave]

I am sooooo confused now! All the plans that I have looked at don't talk about this. In fact they usually say to keep the side of the floor uncoated, so you can glue the sides to it. I have already covered the underside of the floor with asphalt emulsion, but I left the side edges uncoated. Should I go back and coat it with something? I sort of figured the PL adhesive would help seal it up when I glue the sides to it.

Amy

The only reason you would want to seal those glue surfaces prior to gluing it up would be if you had a sawing or routing operation and you didn't want any edge tear out. The PL glue will more than suffice for sealing the edges, and will glue better on an unsealed surface.

BTW...By posting the epoxy pics, I only wanted to demonstrate that a single coat of sealer really doesn't seal the wood...it will still breathe till the second or third coat is applied. I would hate to suggest that you need to seal the interior of a framed wall, although, it would seem to be a good idea to me for a trailer left out in the open in a wet place like Juneau, or if you didn't use a good grade ply. To each their own!!!

[Dean in Eureka, CA]

The first coat of epoxy looks great...life is fine

Question about the first coat:
Was the back side of your gunnel sealed also, or just the side showing in the pic? (IE... Does the surface that is in contact with the work bench have sealer on it also?)