Insulation Questions...

[Guest]

From what I've read about insullating the walls and the roof, about making sure there are no voids of air left inside the insullated cavity...
Am I correct to assume that the wood srfaces of the studs and plywood skins need to be sealed as well?
Another way of wording my question... Should the insulation be glued into place, using the glue also as a sealant... Or should the wood surfaces be sealed first, then use a tight dry fit piece of insulation in the cavity, or glue it into place into the sealed opening?

If the insullation needs to be glued into place, it would be great to find a product that will double as a sealant/adhesive...
What products have you guys used that doesn't attack the white foam board insullation?

On another note, coming up with the right sealant... Has anyone tried a laminated combination of the white foam board and the 1/4" thick double foil faced air bubble insullation?

[Ira]

I think if you have 1 1/2" of wall cavity, fill it wth 1 1/2" of insulation--not 3/4".

I don't think this ever got this technical.

[alaska teardrop]

Dean - Here's a "no glue' idea for you.

http://www.venturetape.com/final/constr ... asp?id=459

http://www.uaf.edu/coop-ext/publication ... -01454.pdf

[/list]

Note that the styrofoam has the best overall qualities in terms of vapor barrier effectiveness, water absorpsion, moisture resistance and R-value.

Fred

Sorry, couldn't get the links to highlight.

Edit: Okay, the links work now! Mike...

[Guest]

Thank You Fred,
Tape is easy...
Looks like I see some of that foil face bubble stuff going on over the stryofoam on the lower radius in your picture...

[alaska teardrop]

Dean- You're welome.

The photo is of the first trailer that I built. The bubble wrap is one of three mistakes in the pic! The floor now gets a full sheet of 1" Blueboard over the top of what you see before flooring.

:)

P.S. can you make those links work?

[fornesto]

If there is concern about the wood being sealed, couldn't you use house wrap over the insulation (on the cabin side) to prevent interior moisture from getting up into the insulated area? This would effectively create a dry zone if done correctly.

[Mitheral]

If there is concern about the wood being sealed, couldn't you use house wrap over the insulation (on the cabin side) to prevent interior moisture from getting up into the insulated area? This would effectively create a dry zone if done correctly.

House wrap allows water moisture to pass thru while keeping out liquid water. You would want to put a vapour barrier on the humid side of the wall to keep moisture from settling in the walls.

I doubt moisture from the inside is what causes travel trailers to rot out though, gross water leaking in from the outside and soaking framing members seems much more likely, especially on a unit with no bathroom.

[Micro469]

If there is concern about the wood being sealed, couldn't you use house wrap over the insulation (on the cabin side) to prevent interior moisture from getting up into the insulated area? This would effectively create a dry zone if done correctly.

House wrap allows water moisture to pass thru while keeping out liquid water. You would want to put a vapour barrier on the humid side of the wall to keep moisture from settling in the walls.

I doubt moisture from the inside is what causes travel trailers to rot out though, gross water leaking in from the outside and soaking framing members seems much more likely, especially on a unit with no bathroom.

What's a bathroom got to do with it?

[Mitheral]

What's a bathroom got to do with it?

Bathrooms have high humidity from all the hot water being used for washing. Leaks in a shower or toilet can go unnoticed soaking insulation and framing members. Also a bathroom on a camping trailer/RV is associated with several penetrations of the shell of the unit (drains, freshwater, vents).

[fornesto]

If there is concern about the wood being sealed, couldn't you use house wrap over the insulation (on the cabin side) to prevent interior moisture from getting up into the insulated area? This would effectively create a dry zone if done correctly.

House wrap allows water moisture to pass thru while keeping out liquid water. You would want to put a vapour barrier on the humid side of the wall to keep moisture from settling in the walls.

I doubt moisture from the inside is what causes travel trailers to rot out though, gross water leaking in from the outside and soaking framing members seems much more likely, especially on a unit with no bathroom.

IMHO, I was thinking of the humidity created by two warm bodies inside of the tear. Putting the barrier facing down would prevent that humidity from getting in the hollow cavity. I believe the humid side of the wall to be the inside. I might of done this had I thought of it ahead of time since I don't have a roof vent. Gross water leakage is bad, but the death of the original teardrops was from inside humidity rotting outward, from what I hear.

[Mitheral]

IMHO, I was thinking of the humidity created by two warm bodies inside of the tear. Putting the barrier facing down would prevent that humidity from getting in the hollow cavity. I believe the humid side of the wall to be the inside. I might of done this had I thought of it ahead of time since I don't have a roof vent. Gross water leakage is bad, but the death of the original teardrops was from inside humidity rotting outward, from what I hear.

Agree totally. House wrap however lets water vapour, like that breathed out by humans, pass thru like wind thru a screen door. You need to use a vapour barrier like polyethelene plastic or two coats of latex paint to stop it.

[oklahomajewel]

From what I've read about insullating the walls and the roof, about making sure there are no voids of air left inside the insullated cavity...
Am I correct to assume that the wood srfaces of the studs and plywood skins need to be sealed as well?
Another way of wording my question... Should the insulation be glued into place, using the glue also as a sealant... Or should the wood surfaces be sealed first, then use a tight dry fit piece of insulation in the cavity, or glue it into place into the sealed opening?

I don't think my Kuffel plans say anything about sealing the interior before applying the insulation....? Is this just an issue about a certain kind of insulation? I noticed near me , as far as I can remember, that the silver foiled board insulation was about the same price as the other blue or pink stuff.

Julie

[Sonetpro]

Couldn't you just spar varnish the frame and wall? I built my walls with Steve Fredrick's method,so I couldn't put a wrap or anything on it as the interior skin is glued to the frame.

[Guest]

Steve,
My inner skin and outer skin will need to be glued to my studwall.
I hadn't seen much discussion about sealing the interior surfaces of the cavity to be insulated, whether or not the insulation was dry set or what have you...
I wanna make time on this thing but I don't want to overlook something that could cause problems down the road... I'll figure something out.
My insulation is going to be more for soundproofing than for heat/cold issues...

[Larry Messaros]

Dean,

The large RV manufacturers do not seal any of the wood framing. As for gluing in the insulation, there isn't a real need given the size of the trailer. If you were building a structural panel, then gluing would be important. I found that press fit works great if you're using a rigid insulation.