Foil Bubble Insulation Methods

[mbatm01]

For those that have used this type - How have you installed this stuff in your ceilings and walls? The post that contained the results of the coating IR tests had a reply where the person installed it with an airgap by using from strips - any pictures or other methods of installation?

Thanks,

Kevin

[fireflyinva]

Kevin,

I've used this stuff as a removable window shading material. I woudn't expect that it would be effective as a replacement for regular insultation, but it was good for the window. It reflected significant amounts of solar heat and was a decent sun block. I've seen it backed with batting for use as an insulating shade (at Hancock Fabrics)--so that makes me think that it may not be an especially good insulator without being paired with some kind of batting material. Perhaps mylar plastic is conductive (although it certainly has excellent reflective qualities)?

Mary

[john hd]

i put it in my chicken coop, just stapled it up!

but, i know it won't help you much!

why do you want to use it in your trailer vs. fiberglass batting?

john

[mbatm01]

John,

There are lots of good reviews on this forum about it - sounds like it performs better than fiberglass batting, and easier to install. Also - I can't find 1.5" batting - any ideas?

Kevin

[malconium]

John,

Kevin may be referring to the test that I made of some different types of insulation in a mock up of an AS wall. You can see about the results in the following location:

http://www.airforums.com/foru...ead.php?t=13363

I think if you study the details you will find proof that foil insulation installed with an air gap on both sides of it in our AS walls will perform better than fiberglass. According to the manufacturers literature is should be possible to acheive the effect of as much as R16 with an airgap on each side of the foil. While this may be a bit optomistic for the way it would be used in an AS there is still no way that 1-1/2" of fiberglass would come anywhere near that. Read about some of the issues with radiant heat loss in the above posting and look at the test results to see for your self.

I am convinced enough to install it in my gutted AS. I bought some 1/2" and 1" thick foam insulation in 4' x 8' sheets at Lowes. I am going to cut them into strips about 1" wide. Here are the steps I intend to take:

1.) Attach the 1" wide strips around the edges of a given wall cavity. I have not finshed deciding what to hold it in place with but I am thinking maybe a little hot glue or some construction adhesive. It only has to be held in place temporarily.

2.) Attach foil insulation to the 1" strips of foam keeping it as straight and tight as possible. The idea is to leave a nice 1" air gap between the foil and the outer skin. Most of my electrical wiring will be running in that space. I am thinking that I might be able to staple the foil to the foam strips. I might need to use some glue and will have to experiment some.

3.) Add 1/2" thick strips around the outside edges of the cavity so that the foil is sandwiched between the 1" and the 1/2" strip of foam. This is intended to help keep the foil 1/2" away from the inner skin. Again I will have to expereiment with glue or maybe even use something like straight pins.

4.) The wall cavity is about 1-1/2" deep and the sandwich of the foam strips and the foil will be slightly larger than that since the foil does have some amount of thickness to it. I intend to use some sort of thin insulation strip on the inner edges of the body bows to help reduce conduction from the outer skin through the bows to the inner skin. I will also go for an insulation strip that is more or less flush with the top of the 1/2" foam strips holding the foil insulation in place. I am leaning in favor of a foam tape of some sort.

5.) As I put the inner skins back on I will have to carefully cut holes in the foil at the right locations to let the wires get through to the inside. I think I will use foil tape around where the wires come through to keep the holes closed.

If you want even better wall insulation go for two layers of foil and 3 - 1/2" thick strips of foam to hold them in place. You might be interested to know that Vintage-Vacations used two layers of foil in restoring a trailer for use as an office in Colorado where the customers main concern was to have an extremely well insulated trailer. Check out the information at:

http://www.vintage-vacations.com/195..._navigator.htm

Foil insulation works differently than we are used to thinking about insulation but it seems to work very well indeed for an AS wall that is only 1-1/2" thick.

Malcolm

[wahoonc]

Originally Posted by mbatm01

John,

There are lots of good reviews on this forum about it - sounds like it performs better than fiberglass batting, and easier to install. Also - I can't find 1.5" batting - any ideas?

Kevin

Kevin,
1.5" batting or 2"? You can small rolls of 2" at the local Lowe's or Home Despot. My reccomendation is to find a steel building insulator or supplier. You can buy faced or unfaced insulation in just about any size you want from one of them. We typically use 6" unfaced in most of our projects, the rolls are normally 60" wide by 50' long. In the past we have also used 2" but the leftovers are long gone. I do use the bubble foil insulation (Reflectix is one brand name) for the windows and the Vista Views. I also use it in my Popup camper in the bunkend windows If I read the directions correctly you need and airgap to get the "rated" R-value.


Aaron

[Tinsel Loaf]

Take one roll of aluminum bubble insulation.
Cut to desired shape and push into place.
To decorate cut to shape spray one surface with sticky stuff. Cover Immediately with a cloth color and type you like. Cut fabric to shape of foil or put glue on edge of bubble insulation and fold over edge. Looks good. Other than folding over the edge you glue piping around edge. Looks good. For skylights place foil between skylight and shade cover and close cover. For fan vents place velcro on edge of vent and edge of foil and stick it. Looks good. Keeps out large quantities of heat in summer and keeps in the heat in the winter. Bonus, makes inside darker so better sleeping during the day naps. You won't know when the sun comes up either.

[john hd]

malcom

i never knew my chickens had it so good!

i know the insulation has very good reflective properties, one 60 watt light bulb is all my hens need to stay warm! and i usually dont even have that on, i just rely on the body heat to keep them warm. the hen house is usually 10 to 15 degrees warmer on the inside vs. outside air temps. 30 outside 45 to 50 inside, they seem quite happy.

i thought the insulation wouldn't work because the aluminum would just wick the heat away via the mylar film. however, your strips of styrofoam would seem to solve that problem.

how do you think it will hold up to travel?

john

[malconium]

John,

I am hoping that it will hold up just fine for travel. I think there are a couple of key things that I need to make sure to do for this to be true. For one thing I will have to make sure that the wires are held in place so that they don't whip around inside the wall and tear the foil loose. I am going to add some more stick on wire ties to do that. Once the foil sandwhich is done and the inner skin is back on I think the foil should be held pretty tightly in place between the foam strips. The foil itself is pretty light so I don't really expect it to tear loose because of its own weight. I will want to check just how tight things are being held togehter before I close up a wall section.

Aaron,

You are right about the air-gap on the Reflectix directions. The foil will still provide insulation if it is in contact with something - just not as much. The instructions show it being used for pipe and duct wrapping for example. I think if I remember correctly they were talking about R3 or R4 in that kind of situation. Still not too bad considering it is so thin.

Malcolm

[till]

My question is how well will the foam (I'm assuming it is rigid) hold up over the long run. I would think that it would start to disinagrate (sp?) with the road vibration. As for adhesivs, are they rated for outdoor use? I would think that you would need outdoor rated sticky stuff due to the tamp cycling the trailer sees.

Don't get me wrong, I like the idea of the foil insulation. The only down side I see is the lack of sound deading ability it will seem to have vs. fiberglass batts.

[wahoonc]

Given the age of my unit (30 years) The fiberglass has stood the tests of time and is still in very good condtion even considering the lack of maintainence that the unit has recieved. Best I can figure other than the sillycone they never recaulked or replaced much of anything on the unit; the old girl has had a hard life but there is plenty of life left in her with plenty of TLC Don't get me wrong I would love to see the results of using a different product, I personally love the reflectix and use it for a variety of uses in my campers, and around the house. BTW how much is the foil wrap going to cost compared to fiberglass? Also anybody know what they use in commercial aircraft for insulation? IIRC when we were out at the Boeing Plant, I saw large skids of fiberglass insulation batts, but did not know if they were for Aircraft or something else that may have been going on

Aaron

[Over59]

That air gap has to be dead air space. If air can get in or out of the space the R goes down fast. Look up the R value for an air gap and you will be surprised. I cann't find my refer manual but I remember it was higher than I ever imagined. Getting a seal around the foil seems a challenge to me. I'll rather fill the walls with a allergy free foam if it didn't deform the interior panels. Didn't some of the old ads have something about "aircraft insulation"?

What is the factory using?

[malconium]

The foam insulation that I have some of is not nearly as rigid as the foam in a styrofoam cup. It is actually a bit rubbery and somewhat floppy. The product name is Insulfoam R-Tech and I bought it at Lowes. The material is expanded polysytrene with visqueen skinned surface on both sides - one side is blue and the other is white. I have a piece here in front of me and find that it bends just fine without cracking and I can squeeze it without it breaking. It basically just bounces back. It does not seem like this type of foam is going to disintegrate like more rigid foam would.

I would suppose that I could also use weather stripping tape of some sort. I think I will have to take a closer look at it since it usually comes with tape on one (or both sides?) side. That might very well be a lot easier to install than the insulation foam because of that feature.

Also I was not expecting the glue to have to hold things in place for much more than the assembly. I expect there to be some compression of the foam and foil sandwich when I put the inner skin in place that will clamp things together. It might make sense to use a thin bead of Vulkum as both an adhesive and a sealer.

It would be interesting to know what the airline manufacturers use for insulation but just because they use a particular product does not, in my opinion, necesarily mean it is the best or only way to go for an AS. There are lots of other consideration such as cost, ease of instalation, etc. that the airlines take into account. Frankly I would be more interested in knowing what type of insulation is used for space craft and fighter jets.

Malcolm

[mbatm01]

I will check out that foam you are using - sounds like the ticket. I was also thinking of a gasket tape also to use as the spacer.

For sealing it - I saw that they also sell foil tape - that might do the trick.

As far as adhesives - there is a 3m spray on rubber cement I have used in the past - works slick, we use to use it to slap drywall shims on steel studs. I cant think of any other type of adhesive that would do the job.

Kevin

[RoadKingMoe]

The problem with air gaps is that if they're too wide a convection current develops, with air rising on the hot side and falling on the cold side. That's why you don't usually see two panes of glass in an insulated window separated by more than about 1/4".

[norbert]

i would think that the spray on insulation would be the most effective...down side is , i believe it gives off formaldahyde vapor... not too healthy though...
norby

[74Argosy24MH]

Originally Posted by norbert

i would think that the spray on insulation would be the most effective...down side is , i believe it gives off formaldahyde vapor... not too healthy though...
norby

That has been banned for awhile. The new foam is safe, for now.

John

[bobechs]

is, I think, the spray-in foam you are referring to. It is very popular with the OTR bus conversion community. Google 'bus conversions' and there you are. A two-part foam, professionally applied. It is not the cheapest form of insulation but it is highly effective and has the major plus of greatly strengthening the structure, according to its advocates. Think monocoque on steroids. As long as the inner skin is off, it looks to me like the ultimate airstream upgrade.

[malconium]

I finally finished installing my new Polyboard sub-floor so I can move on to other things. I spent a little time on a couple of leaks today and then started experimenting with installing the foil insulation in part of the curved back end. I cut some 1" wide strips of both the 1" and 1/2" thick foam insulation (on my table saw) and started with a small section of the wall near the back of the AS. I decided to try using a thin bead of Vulkem as glue to see if it would help hold the foam and foil sandwich in place. It does seem to work OK as long as there is not too much tension on the pieces while it sets up some. So far I think the Vulkem will work but I will have a better feel when I see what it looks like tomorrow. The foil is somewhat stiff so it makes it fairly easy to lay in place so that it holds its location while the Vulkem grabs a bit. The inner wall panel will press the sandwich together more when I install it so as long as the foil and foam stays in place until then I think all will be well.

I do think I would like something that grabs a little tighter a bit quicker though. One interesting problem that I ran in to was caused by the fact that the exterior skin is both a bit cold and a bit damp. I has been raining today and the outside temperature was about 45 degrees. I wanted to add a few wire tie-down straps in a couple of places to hold some wires in place behind the foil. The stick-on wire strap attachments did not stick reliably even when I carefully dried off the aluminum. This also leads me to believe that I would also have a problem with double back tape or foam tape unless there is something out there that is more moisture tolerant than the wire tie downs.

As an experiment I tried gluing a couple of the tie-downs on using some Polyurethane glue that I had that actually needs moisture to set up. The problem with this product, though, is that they will have to set up over night. I left them attached without connecting the wires to them to see what they are like in the mornining.

So here is the question - does anyone know of some sort of fast setting glue that is either moisture/cold tolerant or maybe needs the moisture to set up? What about some type of double back tape that would stick to slightly damp cold aluminum? What can I use for wire tie-downs? Would heating up the aluminum some with my hot air gun help?

Malcolm

[john hd]

malcolm

try 3M auto trim tape, it is very tacky and holds very well. it is very similar to what airstream used to install the windows in 70's trailers.

it may even work for the wire tie downs, if you replace the adheasive that comes with them.

my guess is that it needs to be dry and prepped with denatured alcohol to get the best "stick"

john