Insulation re-do & adhesive woes - what could we have done differe

[Michael M]

Michael might be upset that I'm posting under his name, but I'm too lazy to set up my own account. This is Hillary, and we've been working on a seemingly endless Compact Jr. restoration together. You might have seen our little blog, thistinyhouse.com. Anyway, I thought I'd copy and paste from one of my blog posts, to see if any of you have any suggestions. Please keep in mind that we have an extremely small budget and we don't want extremely toxic materials in our Compact Jr.

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Our first step was lining the inside with Reflectix, a bubble wrap encased in foil. Intended as an eco-friendly, reflective, radiant barrier where its effectiveness is based on how much space it has, we found that it was about the cheapest material we could find at the local home store (about $0.40/sq ft). Eager to get started, I purchase a few rolls of it, some glue canisters and re-lined the fiberglass shell with it.






Though it worked well, the Reflectix was thin and I still wanted more insulation. We researched all the different types of insulation out there — and greener options too — but it all seemed so expensive. Plus, after attending one of Jay Shafer's tiny house building workshops, I wasn't convinced that greener options were better performers. We decided that good insulation was green in and of itself as we would spend less energy heating the place. Ultimately we bought big 3/4-inch-thick sheets of foam board (CFC-free expanded polystyrene) at the local home store (about $0.32/sq ft) and I custom fit them to the slightly curved walls. The result? A high insulating R-value with relatively little thickness.





While this appears to have worked, when leaning against the walls you can tell they weren't properly glued in (they squeak and shift back and forth). This is because adhesive had seemingly cursed my life. We ran out of the stuff we used for the Reflectix and it didn't seem to be available at any home stores anymore. I tried several substitutes but nothing pleased me – who knew that gluing foam board onto foil-wrapped curved fiberglass walls would be so aggravating?

Now I'm thinking I will take some of that GreatStuff insulation spray, peel back what I can of the foam sheets, and spray in there as much as I can… just spray the crap out of it. StickyStuff is a more appropriate name for this product and it would be a big ol' messy project. Any thoughts?

Because of my adhesive woes I have hesitated going forward with trying to adhere anything to the foam board. In terms of materials, I've thought of all different kinds of cheap, lightweight wall lining, even faux fur. If I could afford it I might look into some funky sticky-back paper or adhesive cork, but not at $1, $2, even $3 per square foot. Others have suggested a super-thin wood paneling, but I'm afraid that may bust my practically nonexistent budget for trailer improvements as well. I'm at a loss. Help me get unstuck, so to speak, and get back on track with my trailer renovation! Any comments would be greatly appreciated.

[Tom B.]

Most spray foam is designed to expand (a lot). This will cause a significant problem for your application as it will buldge out the entire piece it is under.

Some may be designed to fill without expanding. Make sure before you spray. It should be noted on the bottle.

Another option is just cheap caulk between/behind the joints. It will set up hard but flexible. Not much insulation but should stop the movement.

Test all first before applying throughout. Good luck.

Tom

[The Hobo]

http://www.lizardskin.com/pages/videos.php

[Lizbeth]

I would contact the maker of the foam board to see if they have any suggestions about adhesives. Spray foam might ruin the whole thing and then that would definitely kill the budget.

I would go with the thin paneling to cover the insulation, but I like the canned ham inside look.

[JOE DRISSEL]

[ Do not use Greatstuff or any expandable foam spray, it will push your foam board right off of the wall.

[Michael M]

Okay, so thumbs down on spray foam. Got it. I'm curious about the Lizardskin stuff. Has anyone used it? Is it heavy? Is it toxic? I guess I could do a search myself.

[Rick kl]

Another consideration is fire, check on its fire resistant properties and what kind of fumes would even a small fire give off

[Frederick L. Simson]

Our first step was lining the inside with Reflectix,

Any thoughts?

How many [b]layers of Reflecix did you glue in? If I remember correctly, Scamp does [b]2 layers beneath their interior "rat fur".

When I rebuilt my Compact Jr. I only did one. If I were doing it over today, I'd also do at least 2 layers. I also chose to cover the interior with [b]the modern version of Oilcloth I bought at WalMart. The oilcloth's vinyl top layer would act as a vapor barrier, and the cotton backing layer (this is the modern replacement, remember) would increase the insulation value slightly, as well as pad the surface and hide defects in my reflectix installation. I used to think of my Compact Jr. as my Padded Cell.

The new owners of my Compact Jr. say it is the most comfortable [b]bedwomb they have ever slept in. They prefer it to their house.

[Coach George Jessup]

read the oilcloth link. What you got at Wallyworld is assuridly the new oilcloth that is not realy oil cloth buttttttt..

I would think the old oil cloth would be a huuuuuugeeeeeee fire hazard. The walls would be like a wick full of oil ready to be lite.

[Frederick L. Simson]

I would think the [b]old oil cloth would be a huuuuuugeeeeeee fire hazard.

I know I have been calling it "Oilcloth" while I think WalMart calls it "Tablecloth".

I have childhood memories of my Grandparent's kitchen, where they had the real thing.

[Cliff]

Looking forward to any thoughts gathered after your get together. Did you come up with any collaborative suggestions? If you already have one layer of reflectix, is it possible to peel back the foam board and then glue up thin carpet? Similar materials like the Casita trailers interior.

[Michael M]

It was great to see everyone yesterday at the meetup! What an interesting mix of people! Frederick and Robert were there, as well as Linda and a bunch of other folks.

As for group decisions on my trailer project, we didn't have any. But it seems that I am the only one who likes the foam board. It makes things so nice and warm! But alas, I might rip it out and add a second layer of Reflectix, then possibly a vapor barrier layer? Then whatever wall fabric/paper I decide on will stick more easily... (No vinyl. Vinyl = toxic.) It will make me sad to see that foam board go, but it's just hard to use in that space.

Hillary

[DonnaMarie]

As a lizard skin "survivor" who paid a LOT of money for it (someone else applied it..for which we paid a ridiculous sum)...I can't advise strongly enough, AGAINST it. it's virtually- WORTHLESS!! Don't even go there!

[k corbin]

I don't have a Compact but I have a similar type of trailer, a Campster. I adhered cedar blocking to the inside of the shell using thickened epoxy. Then I pressure fit foam board between the blocking. I then put a vapor barrier over that using reflextic sealing it to the blocking with aluminum foil duct tape. The finished surface is painted 1/8" plywood.



My ceiling has a layer of EVA foam and the finished surface is a marine vinyl that has a fuzzy backside made for glue.



It is a lot of work, the blocking took the most time, but I have a very cozy trailer and the surface is easy to clean. Absolutely no squeaking because the wall panels are not touching the insulation, they are secured to the wood blocking.



here are some in progress photos of the blocking and insulation plus the reflextic vapor barrier layers. I do have the plywood up and painted but have not yet taken any in progress photos of that stage although some of that white painted plywood can be seen down low below the window.