sealing sandwich floor and walls

[ibbowhunting]

is it the norm to seal (with the mix) the skeleton structure of the walls and floor before installing the sheeting on the floor or walls or just seal the sheeting after the walls and floor are assembled

[daveesl77]

I sealed both inside and out. This may or may not be an intelligent thing to do and only time will tell. With that said, on the inside of the sandwich walls, I thinned TB2 to 50% and used the glue as a sealing coat. The reason I say it may not be smart is that if totally sealed, none of the wood can breath at all. Then again, since I sealed all exterior surfaces, then I guess it doesn't matter. Like I said, only time will tell. I built a hybrid, so I used wood framing and skins, but most of the structure is foam.

dave

[Gunguy05]

is it the norm to seal (with the mix) the skeleton structure of the walls and floor before installing the sheeting on the floor or walls or just seal the sheeting after the walls and floor are assembled

From what I've seen, read, done it was just to seal the outside surfaces.

[KCStudly]

I think a lot of it depends on where you live (rainy and humid ambient conditions require more protection), how you intend to store your camper (indoors vs. sheltered vs. outdoors), and what external treatment you plan to us.

I will be storing mine outdoors for at least three seasons out of the year. I used a water based contact adhesive (between foam and wood) and TB2 (between wood and wood) to stick my foam wall cores to the inner plywood skin, so there is a barrier coat there. On the outside before deciding to do a full blown fiberglass and epoxy outer skin, I used TB2 on the underside and edges of the floor (which would have been covered with more glue and canvas at the edges and paint underneath; and "the mix" around the door frames and at blocking for running lights. Now I will have to scuff these areas up well before applying the epoxy, but if I were building a more traditional aluminum sided TD, I would have still tried to seal up as much of the wood grain as I could before skinning. I would be more worried about the damage that intruding water can do, than the effects of self moisture in the wood.

I think Aggie79/Tom is of the opinion that it is better to leave one side of the wall system unsealed, so that in the event that moisture gets past the aluminum it can migrate out thru the cabin. IIRC, He used a pre-finished T&G flooring product for his interior wall skins and made no attempt to seal the joints between planks or perimeter, but he also did a very thorough job of sealing all of his outer aluminum lap joints, trim and screw holes. UMMV.