|
| Author |
Message |
WILL1E
Moderator
|
# Posted: 15 Jan 2021 08:17am
Reply
As i watch endless youtube videos as i dream about building a cabin, i came across this one.
The guy,
OFF GRID HOMESTEADING With The Boss Of The Swamp, swears by this stuff as an excellent insulator and something the rodents want nothing to do with. In one of his videos, he claims to buy a roadside shabin, laid down a layer of this on TOP of the subfloor, and then laid down another plywood layer (didn't specify thickness of 2nd layer). He claimed he went from the cabin always being hot up at head level but cold at foot level, to a consistent temp from floor to ceiling.
Foil Bubble Insulation
This caught my attention because i've been thinking through the elevated platform i would need to construct for my cabin as discussed here.
The stuff on HD's site claims R value of 3.7-21. So I scanned through the installation guide to see how that was possible with something so thin. I primarily looked for examples related to an elevated platform. Page 14 shows a crawl space install where they attach it to the bottom of the joist and they claim a R16. However, the image might be misleading as i assume when they saw crawl space it means all 4 sides fully enclosed. Page 15 shows the same as 14 but with a second layer hanging between the joist and this gets you up to R21.
Wondering what sort of R value i could expect on a elevated platform build?
Anyone have specific experience (good or bad) with this stuff?
|
|
Nate R
Member
|
# Posted: 15 Jan 2021 08:31am
Reply
Very scammy stuff to claim those R-Values. You won't see that kind of difference in the real world at all.
It's used to insulate the shell of fiberglass hard-sided campers frequently. (Scamps, Casitas, etc). it's better than nothing behind the carpet, but not a lot. If it insulated as well as they claim, the Scamps wouldn't need the heater size they do to stay warm in cold winter.
Air sealing is not the same as insulating.....
|
|
WILL1E
Moderator
|
# Posted: 15 Jan 2021 08:44am
Reply
I thought the same the second he said that about the difference in his shabin. I didn't think bubble wrap could be that magical.
I'll be curious if anyone on here has used it.
|
|
lburners
Member
|
# Posted: 15 Jan 2021 09:03am
Reply
I installed it under my floor sheathing. Im not done my build yet so cant offer any opinion on results. I figured it wouldnt hurt in keeping varmints out. I also probably wont be spending too much time in the Winter up there.
I cant recall exactly but I think someone on here did some actual temperature measurements with the stuff.
|
|
WILL1E
Moderator
|
# Posted: 15 Jan 2021 09:07am
Reply
lburners is your floor elevated? So you pinched this stuff between your sheathing and the joist...did you do any additional insulation below that?
|
|
gcrank1
Member
|
# Posted: 15 Jan 2021 09:21am
Reply
As I understand it, insulations does what it does by creating a dead air space, some materials being better at that than others, but it has always seemed that R value goes up as the material gets thicker. Any thin materials seem to need a reflective element to bounce reflective heat waves back into the space, to me that aint the same as 'insulating'. Maybe the 'box-in' the space with it; ie, a top and bottom layer on the joists or both sides of studs to create that as a whole dead air space?
So, yeah, I find the product of interest but am currently not buying the claims though I think I will seriously consider to buy the product for some of my re-work on our new-old cabin this year.
|
|
Brettny
Member
|
# Posted: 15 Jan 2021 10:34am
Reply
Is this the video where he shows how the ground under his cabin isnt frozen? Well you need moisture in dirt to make it freeze. Theres prob very little moisture in dirt that hasn't seen rain or run off in many years.
I look at bubble foil as a thermal break or a vapor barrier..not an insulation. They also make fan fold 4'x50' foam board that's about $50. It should do the same thing.
|
|
lburners
Member
|
# Posted: 15 Jan 2021 11:42am - Edited by: lburners
Reply
Yeah Will1e my floor is elevated. Its pinched in there. No additional insulation yet. Like I said I dont think I will be up there much in the winter and a woodstove in a 12x 16 should get plenty warm. Im thinking much in the same way as Brett that its basically a vapor barrier. It was easy enough to roll out when putting on the sheathing. Its like a placebo it made me feel warmer just putting it on there.
image20200913_102819.jpg
| 
image20200912_154808.jpg
|  | |
|
|
|
BobW
Member
|
# Posted: 15 Jan 2021 07:10pm
Reply
Does osb or ply get nailed directly on top of this?
|
|
lburners
Member
|
# Posted: 15 Jan 2021 08:36pm
Reply
I used ply but cant see why osb would be any different. Like many on here have stated I wouldn't plan on any amazing insulative (is that a word) properties.
|
|
darz5150
Member
|
# Posted: 15 Jan 2021 10:02pm
Reply
My shop is on skids. No skirting. It has the bubble insulation underneath. It's 32° outside and spitting a little snow and getting ice. It's 70 °
Inside. And the bare floor is 57°. So I assume it helps at least a little bit.
|
|
Irrigation Guy
Member
|
# Posted: 15 Jan 2021 10:19pm
Reply
I used to use it when I was in the HVAC field fir wrapping ductwork. Without an air space the r value is no where near what they claim. I did however use it between my metal roof and purlins to prevent condensation.
|
|
spencerin
Member
|
# Posted: 16 Jan 2021 07:56am
Reply
I installed it as he did. My cabin is open-aired underneath as well. I wanted it because I didn't want moisture or mice underneath.
As previously stated, it's good as a moisture barrier and does provide *some* insulation. The guy in the videos also has skirting that he lined with it as well - that's what really makes the difference, and I believe he says so. I think he's being completely honest and isn't manipulating anything at all.
|
|
SCSJeff
Member
|
# Posted: 16 Jan 2021 09:08am
Reply
I've been interested in this as well for my cabin on piers.... (mainly for the low cost and "ease of installation")
I do spend a few weekends thru the depths of winter and the floors are very cold even when the temp inside is 75 Degrees F. One visit, it was Zero outside and even after getting the cabin to 70 a water spill was still frozen on the floor 
However, I am always battling carpenter ants and am hesitant to do anything below that would make it more "homey" for them.
So here's a thought... How about foam boards glued tight to the floor between the rafters and then install the bubble wrap tight under that?
Of course the flip side to it is.... I have not yet installed a finished floor. This bubble wrap is not vapor permeable. So for instance, I would not want to use vinyl flooring (either sheet or plank) because if a spill (or existing moisture) got trapped in between the two impermeable layers, that would be a problem...
|
|
Brettny
Member
|
# Posted: 16 Jan 2021 09:22am
Reply
Jeff foam board up at the bottom of the sub floor is far superior to this bubble foil. It has actual Rvalue and all the same vapor barrier properties. They make a fan fold foam board that's 1/4" thick and about 3/4 the price of bubble foil.
Any one know where the r3.7-r21 of bubbe foil comes from? That's a pretty wide range.
|
|
gcrank1
Member
|
# Posted: 16 Jan 2021 10:33am
Reply
The R value is probably in the small print somewhere on the instal-instruct..... I suppose if you stack enough layers you can get any R you want 
My 83-84 build I put 1" blue DOW styro on ledger strips between the floor joists and under the floor deck.
I think now I would also put this product down atop the joists before decking, it seems to be cheap and easy enough so why not. Doing so I think would negate any need for 'sealing' the styro edges, just cut nicely snug and drop/press 'em in.
Btw, use whatever thickness (or layer up) of styro you want, I know the 1" is fairly easy to work with, thicker gets harder to cut (I found a fillet knife worked pretty well).
|
|
SCSJeff
Member
|
# Posted: 16 Jan 2021 10:58am
Reply
I'm leaning towards doing a vinyl flooring (probably sheet for keeping costs down). In that case, I also need to be careful about what type of foam board underneath. Can't have the foil backing. And EPS vs XPS. (I know one is more permeable than the other)
|
|
gcrank1
Member
|
# Posted: 16 Jan 2021 11:51am
Reply
Why? Code? Practically speaking, what is going to soak thru the vinyl flooring, then the decking, to get to the foil or get 'trapped' at the foil?
|
|
SCSJeff
Member
|
# Posted: 16 Jan 2021 12:32pm
Reply
I'm thinking burst pipe/leak in the wall or inside cabinets. (flooring will not go under existing cabinets)
Also, any trapped moisture at the time of install.
IDK... I'm just going by the building science website. Should always have one side or the other be vapor permeable to allow moisture to escape. I'd rather be safe than sorry
|
|
Brettny
Member
|
# Posted: 17 Jan 2021 07:08am
Reply
No vapor can get through closed cell foam board and next to no vapor can get behind vinyl flooring, even less if you use a flooring foam or similar product. So in theory there should be no moisture to trap. I'm not really sure how much moisture would even stay in a piece if plywood sub floor.
|
|
SCSJeff
Member
|
# Posted: 17 Jan 2021 12:35pm
Reply
Hey Brett, you're probably right about any "existing" moisture being a problem. I would still worry about a leak in the wall or under the sinks/toilets causing trapped moisture.
For informational purposes, here is the building science's permeability of different building materials:
https://www.buildingscience.com/documents/information-sheets/info-312-vapor-permeance -some-materials
Looks like, depending on the thickness and any facing materials, both EPS & XPS are "vapor semi-permeable" and would be considered safe (IMO) under a vinyl floor. However, in respect to the bubble wrap questioned in this thread, I think that would be a bad idea to place over top then. Of course, I know carpenter ants still like to burrow tunnels through foam board 
|
|
Alaskajohn
Member
|
# Posted: 17 Jan 2021 12:52pm
Reply
I did use that exact insulation last winter. Our cabin has about a 2 foot crawl space between where the plumbing to the septic system is exposed. Last winter we had about 30 days where we had high winds and temps -20 or worse for that whole month. The stuff froze, need I say more. Fortunately I had some of that and a heat tape. The wife and I crawled under the cabin in a windstorm at about -35 below and managed to wrap that insulation around the heat tape. About 6 hours after we turned on the heat tape we were back in business.
I still need to make a permanent fix to the exposed pipes, but our makeshift fix using that insulation is still on until we get to that project which includes more work than just replacing the insulation. This project is on the upcoming summer’s project list.
|
|
gcrank1
Member
|
# Posted: 17 Jan 2021 02:19pm
Reply
Around here (WI) you'd need to hire a licensed plumber to fix that to code and have it inspected....
But Im expecting a lot of people 'just fix stuff' anyway.
Thanx for the tip 
|
|
WILL1E
Moderator
|
# Posted: 18 Jan 2021 07:46am
Reply
Quoting: Brettny Any one know where the r3.7-r21 of bubbe foil comes from? That's a pretty wide range.
|
|
Alaskajohn
Member
|
# Posted: 19 Jan 2021 09:49am
Reply
Quoting: gcrank1 Around here (WI) you'd need to hire a licensed plumber to fix that to code and have it inspected.... But Im expecting a lot of people 'just fix stuff' anyway. Thanx for the tip
We are on our own in the middle of nowhere. Plumbers and code inspectors simple don’t exist.
|
|
|
