Sealing floor? Should I CPES inside and will it affect .....

[ajliquidation]

Building my benroy on 4x8 HF frame, built my floor a month ago and it was way overkill! 3/4 ply wood x2 and not great wood, no worries I made a new work table out of the heavy bastard!!! Now I'm making a 3/8 sandwich fool with foam in the middle now. I will cover the bottom with Henry's roofing tar, my question is do you guys seal the wood first and what about the inside where the foam will be? Any help would be great! Thanks Adam in KC

[tony.latham]

Building my benroy on 4x8 HF frame, built my floor a month ago and it was way overkill! 3/4 ply wood x2 and not great wood, no worries I made a new work table out of the heavy bastard!!! Now I'm making a 3/8 sandwich fool with foam in the middle now. I will cover the bottom with Henry's roofing tar, my question is do you guys seal the wood first and what about the inside where the foam will be? Any help would be great! Thanks Adam in KC

I think you'll find there are many camps on this subject. Without a doubt the traditional method has been the Henry's on bare wood. I've never read where anyone was sealing inside sandwiched walls or floors.

I'm not sure what my first teardrop, that was a commercial product used. It felt soft and certainly wasn't a tar-like substance. After ten years I sold it and whatever had been used seemed fine.

On my first build I used a thinned layer of TB2 glue followed by two coats of enamel paint. I'm fine with it. On my last two builds I've used the thin Raka epoxy. I don't think you can beat that method. I'm convinced the thinned polyester (varnish stuff) would work fine too.

I just tihink there are many ways to skin this cat that work just fine. I see no reason to seal inside the floor.

T

[ajliquidation]

I didn't understand sealing the inside either but, I have seen people painting the the inside before the foam with roofing tar. I figured if the outside was sealed no need for the interior where the foam lies. But I'm a rookie and that's why I double double check!

[kayakdlk]

I sealed the inside floor (mattress side) on mine in case someone spilled a bottle of water etc and it got on the floor. I wanted it to soak into the mattress which is removable and not the floor. I also sealed the edges but not between where the foam went.

Dan

[aggie79]

I didn't seal the inside of my floor or ceiling. My inner wall is pre-finished engineered flooring. The planks are glued to the plywood "framing" but not edge-glued. My surfaces aren't sealed because I wanted them to "breath" to allow a path for water vapor to migrate in case any water penetrated the exterior.

The downside of this approach is that it gives a place for the off-gassing of construction materials and adhesives to go. This has diminished greatly since our teardrop was constructed, plus we always have the vent and/or windows cracked no matter what the temperature is.

If you sealed the interior surfaces you could minimize the off-gassing to the interior.

Regarding CPES, I sealed the bottom of my floor with it. It worked well, but took many more coats than the epoxy I used to seal the outside of the walls and roof. CPES is loaded with solvents. I wouldn't use it on the interior. When you apply it, be sure there is plenty of ventilation. I wore a respirator with organic cartridges during application of the CPES.

[ajliquidation]

Tony- I've seen you mention RAKA before, is it an epoxy or sealer? Or both?

[ajliquidation]

Sorry just saw you called it an epoxy, is it mainly used just for sealing and water proofing?

[tony.latham]

Sorry just saw you called it an epoxy, is it mainly used just for sealing and water proofing?

Raka is an epoxy for marine and shop use. I first used it in on a woodstrip canoe that needed an epoxy/fiberglass coating on the interior/exteroior.

I use it to seal all the exterior wood on a teardrop (and then sheath the sides and top with aluminum). Some builders like to use a thinned polyurethane for the same purpose. I think the difference between sealing with an epoxy vs a poly-varnish type is that epoxy sets up -curing chemically– while polyurethane evaporates and thus is somewhat porus (that's why they do multiple coats).

Here's Raka's website: http://www.raka.com/epoxy.html

I use their pumps since the mix ratio is 2:1 and I've never mixed a bad batch that way.

Tony

[bobhenry]

This picture is of Eggbert my very first mini build in early 07.

It was last seen setting in the mud behind my foreclosed house last spring.
Despite being abandoned to the elements for years and setting directly on the ground
the white polar seal roof coating protected the osb from the elements completely.
Goes on thick and fills in cracks and voids well. It dries to the touch in about 4 hours
making multiple coats possible in a single day. It does chalk up a bit but it does accept
paint well and made an excellent undercoating.

[tony.latham]

This picture is of Eggbert my very first mini build in early 07.

It was last seen setting in the mud behind my foreclosed house last spring.
Despite being abandoned to the elements for years and setting directly on the ground
the white polar seal roof coating protected the osb from the elements completely.
Goes on thick and fills in cracks and voids well. It dries to the touch in about 4 hours
making multiple coats possible in a single day. It does chalk up a bit but it does accept
paint well and made an excellent undercoating.

Looks like some good stuff, Bob!

T

[ukewarrior]

Regarding Henrys.....
I read very mixed reviews of this stuff.
Reports are that it takes a very long time to dry. As in days.
True?
Is the motivator to use Henrys the price?
Is there a list of alternatives posted anywhere?
I see in the post above that Polar Seal white roof coating gets a very positive review.
How about others?
Are these products sufficient to seal the ends of plywood or should I stick with a poly mix for edge sealing?
I'm currently interested in the NON-Viewable part of the build for this discussion.

Building my benroy on 4x8 HF frame, built my floor a month ago and it was way overkill! 3/4 ply wood x2 and not great wood, no worries I made a new work table out of the heavy bastard!!! Now I'm making a 3/8 sandwich fool with foam in the middle now. I will cover the bottom with Henry's roofing tar, my question is do you guys seal the wood first and what about the inside where the foam will be? Any help would be great! Thanks Adam in KC