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Rigid styrofoam insulation

Posted:
Sat Dec 03, 2011 1:24 pm
by GuitarPhotog
I'm planning to use 1" rigid styrofoam to insulate my teardrop. It will be applied (glued) directly to the interior of the aluminum skin, and the interior will be covered with hull liner.
I have heard "blue beadboard" cited at the preferred form of this stuff, but out here on the left coast, it's not so common. I find lots of white styrofoam, with a foil on one side and a plastic film on the other.
If I can't find blue beadboard, can/should I use the white stuff?
I'm planning to use 3M Fastach 30NF contact cement, partly because of its high-temperature properties. The skin of the trailer gets to 140F on a hot day in the sun.
Suggestions are welcome.
<Chas>

Posted:
Sat Dec 03, 2011 3:39 pm
by Moho
I don't know this for a fact but I woul assume the "white" styrofoam you are refering to has larger sized little balls which aren't as dense? I would assume that the little balls would have a tendency to come loose over time with vibration and such before the Blue Polysterene would. This would cause deteriorated panels over the lifetime of the trailer.
Also consider that different types of board insulation have different R values.
Maybe someone with knowledge can confirm what I said about the white board.

Posted:
Sat Dec 03, 2011 4:45 pm
by LWW
I used a combination of both on mine. I had some of the blue board and ended up buying a couple of sheets of the white to finish the job. the blue was 1/2" and the white was 1". I just figured 1" of something was better than no inches of nothing. Larryw

Posted:
Sat Dec 03, 2011 7:10 pm
by GuitarPhotog
The white stuff doesn't have distinct little "balls" or beads, so I don't think that's a worry.
1" of the white stuff is only R-3, but that's better than the R-0 I have now. At least the interior walls won't be so cold (or hot) that I can't touch them.
<Chas>

Posted:
Sat Dec 03, 2011 9:01 pm
by afreegreek
there's no need to glue it in place, just cut it for a snug fit.. EPS will not fall apart either unless it has been exposed to UV light for a very long time..

Posted:
Sun Dec 04, 2011 2:48 am
by GuitarPhotog
I think there are going to be too many pieces to simply friction-fit into place, and I wouldn't want the ceiling panels falling in after traveling a pot hole-filled road.
I think glue is a requirement
<Chas>

Posted:
Tue Dec 06, 2011 7:43 am
by Lgboro
Be sure to test your preferred glue prior to use as I have found this type of insulation to react to most glues. I used Gorilla glue and it worked very well. My insulation is part of the structure as I will have no exterior wood just floated aluminum and thin cedar strip for the interior. I have two 3/4 inch layers glued in for 1 1/2 inches of insulation due to the heat of eastern NC and wanting to have my tear double as an emergency shelter during hurricanes, ice storms, etc. The big box stores should have the blue or pink insulation in stock in your area.

Posted:
Tue Dec 13, 2011 6:07 pm
by GuitarPhotog
The big box stores hereabouts have only white, but in a myriad of thicknesses. I chose 1" because that fits the depth of the frame ribs.
I think Gorilla glue has too much expansion factor and would push the foam away from the metal skin, making it difficult to get a smooth interior for upholstery.
The 3M Fastach 30F adhesive has been recommended several places, but it's very expensive ($25/pint), so I'm hesitant to buy a pint just to test.
My Hull Liner fabric arrived last week. It looks like exactly what I want. Thanks to whoever recommended it.
<Chas>

Posted:
Wed Dec 14, 2011 7:14 am
by bobhenry
The closed cell foam board all starts out as white. Dow dyes theirs blue owen corning dyes theirs pink and yes Virginia there is even a green one the company escapes me however.
I used mostly aluminum faced polyisocyanurate as the thermal r value was far superior ( and I had it laying around) I jam fit it in the voids also and to make sure it stayed put I simply taped it in place with the butyl rubber construction tape normally used around windows and doors.


Posted:
Wed Dec 14, 2011 2:16 pm
by GuitarPhotog
That butyl rubber tape idea is good, but because the skin temperatures on my teardrop often reach 140F and higher in the sun, it just melts and drips down the side
I'm still trying to remove the resulting gooey mess from the experiment.
My friend in the exhibit building trade uses something they call "OMG tape" to hold panels in place while the glue dries, but he doesn't know what it is sold as. It works great holding stuff to hot metal. But he has only a little and we can't source it.
<Chas>

Posted:
Wed Dec 14, 2011 4:07 pm
by aggie79
I'd be tempted to try a glue test of the foam to scrap metal or aluminum using PL Premium (the stuff that comes in the caulk gun tubes.)
This adhesive is pretty thick (viscous?). You may want buy a cheapo plastic notched trowel to spread the stuff out before sticking on your insulation.

Posted:
Mon Jan 02, 2012 10:30 pm
by jrigs
Definitely test your glue. When I attached my hull liner directly to foam each of the contact cements I tried ate the foam. I ended up using Elmers spray adhesive. I had never heard of it before but it worked great.

Posted:
Mon Jan 02, 2012 11:55 pm
by GuitarPhotog
I intend to test everything before getting started.
I have the glue and hull liner, and 1" rigid styrofoam is abundant locally. I'm just waiting for a bit of warmer weather so the garage gets above 65F.
<Chas>

Posted:
Tue Jan 03, 2012 10:50 am
by Robbie
I glued some of the 1" Dow Corning pink foam to the bottom of my trailer this past week and I used the Loc-tite PL Premium construction adhesive. It says on the tube it is safe for foam and it really creates a strong bond. I'd be shocked if that bond ever broke loose without being ripped off. I just put a bead around the perimeter and a few dabs in the field and just pushed it up there good. I plan to use the same stuff to hold it in place when I do my roof.

Posted:
Tue Jan 03, 2012 11:17 am
by Forrest747
Friction
I just had my blue Dow insulation just held in place with friction and then sandwiched when i put the cherry paneling in.
The roof panels when i get to that point will just be layed in and roof placed over it.
Love teh blue insulation and using white for teh front end and roof. love teh blue much more than the white.
One thing about the blue i loved is i could press it up against teh wall and it left an indentation where i knew i could cut. the white i never can see it.