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Hi everyone!  I love this forum so much that I decided to finally join  Big Grin  

Just to provide some background, i plan on the most epicest most amazingest &%#! van build evarr...  haha.. basically what I mean is I am looking for a best of breeds approach using the latest and greatest technology that is available on the market, and that includes insulation.  As everyone knows, insulation is very very important because we spend so much effort on solar/power and HVAC systems, which i think should be the heart of any van build unless you have the option of always traveling toward better weather (something i don't have - and i anticipate anything between very hot to freezing temps).  So, the conclusion I came to for using on my 2016 Ford Transit was using custom sized Vamum Insulated Panels on the side and the ceiling, and Aerogel Spaceloft fabric (which is now available on EBAY) material layered and folded up to fill in the gaps between panels and as an additional layer of insulation over everything.  Within any crevices, such as within the hollow support beams, I plan on first spraying Flex Seal to act as a vapor barrier and to fill in as much of the crevice as possible.  On top of that, I plan to use 100% silicone caulk, which will help dampen vibrations (i.e., noise) but mainly for its thermal properties.  On top of the still uncured silicone, I would like to stuff in pieces aerogel whever I see any remaining space, and then an adhesive vapor barrier lining on top of that to cover any exposed areas once the silicone has cured.  I also plan on using the silicone to fill in any gaps I can find between the VIPs and the Spaceloft.  Now, I've never done anything like this before, so I have a few questions about the silicone sealant:

1.  Is the performance of silicone sealant recommendable, as opposed to a something like a polyeurathane-based sealant, or 3M 5200, or maybe something like Green Glue, in terms of thermal properties and noise dampening properties, and longevity because I don't ever plan on ripping out the insulation.  One thing that I noticed is that silicone sealant is used by the factory on many areas in cars, so it must be a good choice.

2.  Do i need to worry about the silicone not bonding with or breaking down the chemical properties of Aerogel Spaceloft?  If I don't need to worry, then wouldn't it also be okay to use silicone sealant to layer sheets of spaceloft?

3.  Is silicone sealant going to adhere well to the paint job?  If it was bare metal of course I wouldn't worry about this...

Thank you!  I love this forum ohhh yea babyyyyy!!!!!!!!
it depends what you are doing with it.

silicone comes in many, many variations. the main problem with it is nothing sticks to it including more silicone. it's also a pain to remove. once silicone is applied, it better work or you will have problems. Permetex Ultra line of silicone is great for use on engines.

I like 3M 5200 if you need both an adhesive and a sealer.

I like Dicor for a self leveling sealer on flat roofs.

so a lot depends on the use. highdesertranger
(02-04-2016, 10:50 AM)danman81 Wrote: [ -> ]  So, the conclusion I came to for using on my 2016 Ford Transit was using custom sized Vamum Insulated Panels on the side and the ceiling, and Aerogel Spaceloft fabric (which is now available on EBAY) material layered and folded up to fill in the gaps between panels and as an additional layer of insulation over everything.  
Danman welcome  to the forums.  I assume you meant Vacuum Insulated Panels (?).  I was wondering when someone would be creative enough to try something like this--along with the Aerogel fabric.   It's too bad there is not a world wide push to make these cheaper and more common-- like is currently being done with LEDs, EV's and battery technology.  Imagine the energy (and $$$) savings if Aerogel was used in refrigerators alone--I'm sure a much smaller compressor would be needed.
Sorry if I got off track but this stuff could be life changing for the planet one day.  Please keep us posted (with pictures if possible) on this first-of-kind (?) project.
Hi danman, welcome to the forum! You will find a lot of great information in the archives here...one of the first things I learned about planning my build is that my "plan" changes rather fluidly...I feel very fortunate that I didn't jump in and build right away, I would have done things I regretted later.

I can appreciate your desire to use "the best" ingredients when making your build, especially when you're doing foundation work that you hope won't need to be disturbed or re-done for the life of your build. In this case, with what you're looking at for insulation, I have a feeling that taking it a bit too far. If it was simply a matter of "I can afford the best and want it", I'd say sure, why not. However I can see a few possible problems with those materials.

First tho, look at the bigger picture...you can't easily get around some of the built-in flaws in vehicle construction, namely glass, door seals/panels, and structural supports. Vehicles leak R-value, heater and AC units have no problem doing their thing even in moderately insulated vehicles, so is it really worth spending thousands on space-age materials? I looked up pricing on VIPs and Spaceloft... I don't believe that thousands is an exaggeration? Spaceloft looks to be about $5 sq/ft ...amazing R-value of 10+ per inch.

Vacuum Panels (VIPs) are interesting, however they rely completely on maintaining that vacuum to work...and you cannot cut or shape VIPs to fit. So even if you got them installed, any modification later would ruin it...mounting panels, fans, exhaust vents, re-wiring, etc etc. Not only that, but this from the wiki page: " Aerogels are more difficult to manufacture than polyurethane foams or mineral wools, and strict quality control of manufacture of the membranes and sealing joins is important if a panel is to maintain its vacuum over a long period of time. Air will gradually enter the panel, and as the pressure of the panel normalizes with its surrounding air its R-value deteriorates. Conventional insulation does not depend on the evacuation of air for its thermal performance, and is therefore not susceptible to this form of deterioration."

Spaceloft is described as "dusty" and "Hydrophobic Yet Breathable, repels liquid water but allows vapor to pass through". Which tells me two things: 1) its not a vapor barrier and 2) I could certainly anticipate adhesion issues with some products, silicone being one of them.

Lots of factors to consider and options to look at...I kinda hope you do it anyway, as it will probably be a first in the DIY RV world Smile
(02-04-2016, 09:22 PM)JT646 Wrote: [ -> ]Danman welcome  to the forums.  I assume you meant Vacuum Insulated Panels (?).  I was wondering when someone would be creative enough to try something like this--along with the Aerogel fabric.   It's too bad there is not a world wide push to make these cheaper and more common-- like is currently being done with LEDs, EV's and battery technology.  Imagine the energy (and $$$) savings if Aerogel was used in refrigerators alone--I'm sure a much smaller compressor would be needed.
Sorry if I got off track but this stuff could be life changing for the planet one day.  Please keep us posted (with pictures if possible) on this first-of-kind (?) project.

Thanks for the response!  Yes, i meant Vacuum Insulated Panels, or VIPs for short.  I just think VIPs are a great idea (not sure why someone didn't think of it sooner) and you get the best performance (by far) compared to any material material out there.  Even if VIPs only perform at half their advertised R-value, it's still going to perform much better than any type of foam panels.  People who make DIY/custom refrigerators/freezers are now using VIPs as well as Aerogel, and I would think are plenty of specialty applications for these modern insulation technologies, for example in the scientific world and boats and yachts (lots of millionaires and even some billionaires there), and of course RVs.   The price is too high for large applications like housing and building (although it has been done), so I'm not sure if we're going to see a big push for it everywhere (i.e., home depot) until the cost comes down more, but I figure a van (mine is a low roof, short wheel base) is not so large that it would be too cost prohibitive (but not cheap by any means).  Plus, space is already limited in a van, so getting better insulation and losing less space at the same time is a win-win for me, and at 10mm thin for Spaceloft, I could easily have multiple layers (assuming I find the right adhesive).  The van itself is still on order with ford (should be arriving this month) and I'm still in the design phases right now, but i will be sure to post pictures and everything once I get the van and start insulating!
(02-04-2016, 08:23 PM)highdesertranger Wrote: [ -> ]it depends what you are doing with it.

silicone comes in many, many variations.  the main problem with it is nothing sticks to it including more silicone.  it's also a pain to remove.  once silicone is applied, it better work or you will have problems.  Permetex Ultra line of silicone is great for use on engines.

I like 3M 5200 if you need both an adhesive and a sealer.

I like Dicor for a self leveling sealer on flat roofs.

so a lot depends on the use.  highdesertranger

Thanks for the response!!!  I am indeed trying to find the best possible sealant I can find -- As you say, it looks like silicone won't stick to things the best, so i'm thinking of looking for a separate adhesive (maybe green glue?) for attaching sheets of spaceloft and attaching other things like panel insulation.  Now, I'm thinking silicone would best be used as a gap filler -- for example in between insulation panels and I'm thinking primarily inside the hollow support beams and basically just any crevices I can find because heat leaks out of gaps as you already know..  What made me interested in silicone is that it's itself insulating -- e.g., silicone pot holders.  Plus, silicone seems long lasting (i.e, permanent or semi-permanent) and stays flexible which I think would help it absorb noise (but not on the level of green glue).  Would you recommend the Permetex Ultra over the popular GE Silicone II?  

I've heard good things about 3M 5200 as an adhesive/sealer, but I'm currently leaning toward silicone because it has better thermal properties and is more flexible (i.e., noise dampening, but I could be wrong about that), and I think if you called what i'm using it for, "gap filling", that would probably be the most accurate.  However, it would be in direct contact with the aerogel spaceloft, so I want to make sure there are no contradictions with any solvents and things like that.  Now, especially for the insulation, there is only so much I can plan, and at some point I will just have to order the material and start insulating, so I do expect a little bit of improvisation at least.  For example, I would like to basically stuff strips of aerogel down the hollow support beams, but there would still be air gaps, so I'm thinking of just pouring the silicone down in there all around the aerogel, i mean why not?  (although, curing it is going to a long time i would think but that's okay)  I was thinking of using a foaming sealant, but it expands too much and wouldn't last as long.  Another thing I liked about silicone is that it doesn't use solvents like a lot of the newer sealants out there so there's less contradictions with different plastics and things like that, although I could be wrong about aerogel.  There's just no documentation on this I could find on this.  Looking more into it, the closest thing I find is the following patent that describes a "binder layer comprising a silicon-containing organic material" that is bonded to aerogel, but that's it:

http://www.google.com/patents/US20060263587

Of course, silicone is inorganic, but here is at least a case where it was used in conjunction with aerogel.   The Dicor stuff looks interesting as well and I will be looking more into it!!
(02-04-2016, 09:29 PM)BradKW Wrote: [ -> ]Hi danman, welcome to the forum! You will find a lot of great information in the archives here...one of the first things I learned about planning my build is that my "plan" changes rather fluidly...I feel very fortunate that I didn't jump in and build right away, I would have done things I regretted later.

I can appreciate your desire to use "the best" ingredients when making your build, especially when you're doing foundation work that you hope won't need to be disturbed or re-done for the life of your build. In this case, with what you're looking at for insulation, I have a feeling that taking it a bit too far. If it was simply a matter of "I can afford the best and want it", I'd say sure, why not. However I can see a few possible problems with those materials.

First tho, look at the bigger picture...you can't easily get around some of the built-in flaws in vehicle construction, namely glass, door seals/panels, and structural supports. Vehicles leak R-value, heater and AC units have no problem doing their thing even in moderately insulated vehicles, so is it really worth spending thousands on space-age materials? I looked up pricing on VIPs and Spaceloft... I don't believe that thousands is an exaggeration? Spaceloft looks to be about $5 sq/ft ...amazing R-value of 10+ per inch.

Vacuum Panels (VIPs) are interesting, however they rely completely on maintaining that vacuum to work...and you cannot cut or shape VIPs to fit. So even if you got them installed, any modification later would ruin it...mounting panels, fans, exhaust vents, re-wiring, etc etc. Not only that, but this from the wiki page: "  Aerogels are more difficult to manufacture than polyurethane foams or mineral wools, and strict quality control of manufacture of the membranes and sealing joins is important if a panel is to maintain its vacuum over a long period of time. Air will gradually enter the panel, and as the pressure of the panel normalizes with its surrounding air its R-value deteriorates. Conventional insulation does not depend on the evacuation of air for its thermal performance, and is therefore not susceptible to this form of deterioration."

Spaceloft is described as "dusty" and "Hydrophobic Yet Breathable, repels liquid water but allows vapor to pass through". Which tells me two things: 1) its not a vapor barrier and 2) I could certainly anticipate adhesion issues with some products, silicone being one of them.

Lots of factors to consider and options to look at...I kinda hope you do it anyway, as it will probably be a first in the DIY RV world   Smile


Wow, thanks for the amazing response from everyone -- I love this forum!!!  You are very correct that I am looking for a best-of-breeds approach -- I'm not trying to brag or anything, but I'm not the type of person that wants to live in a van to save money or because I "need" to and I know a lot of people dont, and actually i think there's somewhat of a surge happening now with people who are thinking more outside the box, especially as technology is improving and products are just becoming more and more efficient as a result.  People (like the amazing people on this amazing forum) are realizing that you don't have to live in a single family home with 2.5 bathrooms and a white picket fence and perfectly trimmed lawns and all that stuff and with garages and closets full of crap no one even needs.  For me, there's just no reason to live in a $0.5M or $0.6M home that I don't even have time to live in when I can spend 1/10th of that on the most modern, technologically advanced RV van build there is and have the freedom to go anywhere, anytime.  If you think about it, at that price you don't even have to sell your home and you can just rent it out or something. You might say, oh well 2, 3, or even 4K is too much to spend on insulation, but if you take into account how much you could put into today's solar system (e.g., a single LiFePo lithium battery bank can easily cost 4K alone or more), it seems like a waste to just let all that effort dissipate out the van, right through the walls.  Plus, being stuck in a cold van in freezing weather after a series of cloudy days is something I'm scarred of, even if I have a Chihuahua and blankets to keep me warm.  I just feel like with today's technology there is just no need to live like that.  Also, hehe, mentioning my dog, and having a full time job, I get worried about leaving him in the van 8 hours at a time in the winter or summer.  The solar system, HVAC system, insulation system must be efficient enough that I can keep it running 24/7, and with the refrigerator (although those can now be very efficient too).  Yes, I do want to be comfortable anywhere I travel to and anytime of the year but i'm probably more worried about my dog than anything else to tell you the truth. You are right that housands of dollars on insulation alone is a lot and it's not for everybody that's for sure, but the reason i'm doing this is to have freedom and live my life to the fullest and has nothing to do with saving money even though I will be -- and it is a great way to save for anyone else out there "on the fringe".

Haha, anyways, sorry i hope that wasn't too off-topic.  You are right that there's lot of room for leakage in a van and that was a huge concern for me and heat travels through them like water.  I won't have windows because this is a white cargo van (stealth ohh baby baby!), and I will be putting in a metal partition behind the front seats that will also be insulated so that the front cabin acts like a barrier zone much like in an earth ship home.  Thermal leakage is also another reason why I'm trying to find the perfect sealant so i can be sure to plug up any holes that I can, while still being able to open the doors and things like that.  I decided on a low-roof, short wheel base van on a number of reasons (a little out of scope again, hehe), but having less space to climate control and increasing HVAC efficiency was one of them.   You mention the structural supports which is something I am worried about, and I would definitely like to fill them with threaded strips of fabric insulation and/or sealant with insulating properties (e.g., silicone).  I've also thought of getting it insulated professionally with spray foam, but foam has longevity issues, meaning it doesn't absorb vibrations well.  I also thought about professional installations like for reefer vans but it's so thick there wouldn't be enough space to live and would cost more too.  

In terms of VIPs, you are correct that they cannot be shaped or cut, and even with custom-size VIPs, you're not going to get a closer size than cutting it yourself with rounded corners and things like that, and that is definetley something I worry about.  You also have to be careful not to puncture it with screws or anything like that, but I think I'm going to have a layer of plywood over all the insulation so I'm not too worried about damaging it.  One thing that cannot be avoided with VIPs is that the performance will deteriorate over time as air seeps in as you say.  But then, I thought, you are going from "R-40" all the way down to the regular insulation value of the foam or whatever they use in there in the case it gets completely punctured, so it's really not that much worse than a conventional foam panel in the end, or even a "high performance foam panel" with an R value of max 6 or 7 maybe.  More expensive, yes, but I don't see it as worse performing in the long run, but please anyone correct me if anyone sees otherwise.  I'm trying to learn and plan and improve my plan as much as I can before I start building.  Anyways, here's a link to some of the "more afforabally" priced VIPs I'm talking about:

http://www.rparts.com/index.php?cPath=84_32

If anyone finds a better value, I would love to know!  

In terms of spaceloft, you are correct that you would want a vapor barrier.  That company actually sells another version of spaceloft that has an attached foil vapor barrier for cold applications like freezers.  I would use an adhesive (haven't decided on which one) to attach the spaceloft, and then seal it all in with an adhesive backed vapor barrier on top of that (sealed at the edges), and then probably repeat like that.  In addition, I'm not too fond of breathing in aerogel dust (no matter how "non-toxic" it is, because I'm sure it still is), so I'm hoping a vapor barrier will minimize dust issues.  

My backup choice for spaceloft would probably be thinsulate if I see too many problems, but used in the same way pretty much.  I've also considered blue jean denim insulation becuase there's no dust to worry about, but it absorbs moisture.
Hey Everyone -- Just wanted to say thanks for the overwhelming responses -- I think this might be the best single forum for this kind of stuff!  I didn't want you to get bored by my responses cause I'm realizing they are pretty long, just wanted to summarize some conclusions and go back to the original thread:

Silicone sealant sounds like the best gap filler.  It lasts a long time, vibration dampening (i.e., dries rubbery), and is thermally insulating (which is the most important).  It sounds like silicone is going play well with other plastics since there are no solvents (which also means silicone doesn't shrink from what I understand), and i'm hoping it won't conflict with aerogel spaceloft.  From an adhesive standpoint, silicone is not the strongest thing, so I still need to decide on a good adhesive.  I'm thinking maybe a spray-type adhesive for sticking on the spaceloft (not sure what kind yet tho) and perhaps Green Glue for more "structural" adhesive because of sound dampening properties (e.g., behind the final plywood layer).  

So much to plan and i can't wait to get started on this build, but i'm covering as much groundwork as possible before i start!  i will post pictures!!  thanks everyone!!!   Heart Heart Heart
I have been building things since the 1960's.  One piece of advice.

D. O. T.   Don't Overthink Things.    Cool

With what you are proposing I do not see much possibility of it happening.  24/7 AC? Using a regular cargo van you would have almost no living room building it to R~40 specs. (11 inches) 

I have a layer of thinsulate on my floor with Advantec and carpets over that.  That works out perfectly.  

As for sealant, go to any hardware store, and read the cover tags on the bins.  As long as you seal the hole, most modern products only differ in moisture resistance or paintability.
The vacuum insulated panels are awesome that's for sure. I have a thing against thermal breaks, though. I place more value over having a complete sheet of insulation rather than have the best insulation possible, but having gaps or breaks in the insulation.
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