Sprinter-Forum    
 

Go Back   Sprinter-Forum > Sprinter-Based RV's & Conversions > Sprinter RV's & Conversions Talk

Sprinter RV's & Conversions Talk Common features found in Sprinter RV's and Conversions.

support Sprinter-Source.com
Click here or the banner before shopping at Amazon. A percentage of your purchase goes to support Sprinter-Source.com

Reply
 
Thread Tools Display Modes
Old 10-04-2015, 08:14 AM   #11
ddunaway
 
Join Date: Oct 2014
Location: Seattle, WA
Posts: 389
Thanks: 89
Thanked 179 Times in 93 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

jghutchinson.

Generally speaking there are 3 kinds of heat transfer: conduction, convection, and radiative heat transfer. Reflectix works by reflecting radiant heat. All surfaces are emitting radiant heat at all times. Hotter surfaces emit more radiant heat than cooler ones. The material of the surface also affect the amount of radiant heat. Without an air gap the aluminum of the reflectix will just conduct heat though the bubbles provide some insulation. Conduction is via direct contact and provides the fastest heat transfer. Aluminum reflects heat efficeintly but also conducts heat quickly (good and bad for insulation respectively). There are also some nuances of whether it is hot outside or inside and on which surface (facing inside or outside) you have the reflective layer.

Reflectix is cheap. I am using it in areas where I have extra space between the Thinsulate and the wall, for example the lower parts of the van where the space is thicker than the 1.75 in Thinsulate.

There are some areas where reflectix is good but it is probably not the main product to use for insulation. If you do not have an air gap you should use something else for that location.....
__________________
2015 High Roof 144WB Crew 4x4

Last edited by ddunaway; 10-04-2015 at 08:17 AM.
ddunaway is offline   Reply With Quote
Old 10-05-2015, 03:20 AM   #12
roblee
 
Join Date: Aug 2014
Posts: 71
Thanks: 52
Thanked 31 Times in 24 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

EPA and Florida Solar Energy Center have a lot of info on radiant barriers. Bottom line: A properly installed barrier in an attic of a home in the southeast US could realize a maximum reduction in yearly cooling energy use of 8-12%. These installs are for attics where the air space is very large, the ceiling is insulated, and the air space is VENTED (like all attics must be to prevent condensation. This is a big difference than a van application. ddunaway's use of reflectix seems appropriate; put it in areas where a little more insulation is needed.
roblee is offline   Reply With Quote
The Following User Says Thank You to roblee For This Useful Post:
Wbp3 (10-09-2015)
Old 10-06-2015, 04:12 AM   #13
jghutchinson
 
Join Date: Aug 2015
Posts: 49
Thanks: 2
Thanked 19 Times in 13 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

My thought process is that if it is not being used as a reflective barrier then surely the money could be better spent on a product that works more effectively as a thermal barrier with a higher r value. For what you are getting in terms of how it is being used in the van conversions... a roll of bubble wrap would achieve essentially the same thing and save you a pretty chunk of change.
jghutchinson is offline   Reply With Quote
Old 10-06-2015, 04:44 AM   #14
roblee
 
Join Date: Aug 2014
Posts: 71
Thanks: 52
Thanked 31 Times in 24 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

+1
roblee is offline   Reply With Quote
Old 10-06-2015, 04:44 AM   #15
mofo989
 
Join Date: Sep 2012
Posts: 466
Thanks: 33
Thanked 88 Times in 64 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

I used 3M Thinsulate covered with Tyvec Thermawrap which has a metalized reflective coating which increases R-value due to reflectivity, but remains vapor permeable. It's thinner compared to Reflectix, and achieves the air-gap requirement as mentioned.
mofo989 is offline   Reply With Quote
Old 10-09-2015, 04:57 AM   #16
Inertiaman
 
Join Date: Dec 2014
Location: Seattle
Posts: 867
Thanks: 39
Thanked 428 Times in 263 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

Quote:
Originally Posted by mofo989 View Post
I used 3M Thinsulate covered with Tyvec Thermawrap which has a metalized reflective coating which increases R-value due to reflectivity, but remains vapor permeable. It's thinner compared to Reflectix, and achieves the air-gap requirement as mentioned.
The Thermawrap products are interesting. You are referencing the "LE" version which, as you note, is sort of Tyvek with a metalized coating. But they also have "Thermawrap R5.0" which frankly seems a lot like Thinsulate but cheaper. Its hard to find online, but I see a Home Depot page that shows it about $1/sq-ft (though I couldn't seem to come up with a zip code that actually had availability).

$1/sq-ft for 1.5" R-5 hydrophobic polyester insulation might be a compelling alternative to Thinsulate, no?

EDIT: I see now that it seems unavailable in USA Home Depots, but it is stocked at Canadian Home Depot. $169 Canadian for 4'x40'.

Last edited by Inertiaman; 10-09-2015 at 05:00 AM.
Inertiaman is offline   Reply With Quote
The Following User Says Thank You to Inertiaman For This Useful Post:
FatChance (10-23-2015)
Old 10-09-2015, 05:07 AM   #17
mofo989
 
Join Date: Sep 2012
Posts: 466
Thanks: 33
Thanked 88 Times in 64 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

Quote:
Originally Posted by Inertiaman View Post
The Thermawrap products are interesting. You are referencing the "LE" version which, as you note, is sort of Tyvek with a metalized coating. But they also have "Thermawrap R5.0" which frankly seems a lot like Thinsulate but cheaper. Its hard to find online, but I see a Home Depot page that shows it about $1/sq-ft (though I couldn't seem to come up with a zip code that actually had availability).

$1/sq-ft for 1.5" R-5 hydrophobic polyester insulation might be a compelling alternative to Thinsulate, no?

EDIT: I see now that it seems unavailable in USA Home Depots, but it is stocked at Canadian Home Depot. $169 Canadian for 4'x40'.
Interesting product. It came out after I did my van. I see it is 1-1/2 thick... might work. I'd love to see a sample to understand how easily it can be folded and tucked into tight places like the Thinsulate. Thinsulate certainly is meant for acoustic damping and is intended for automotive, so it does have that going for it.
mofo989 is offline   Reply With Quote
Old 10-09-2015, 05:11 AM   #18
Inertiaman
 
Join Date: Dec 2014
Location: Seattle
Posts: 867
Thanks: 39
Thanked 428 Times in 263 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

Quote:
Originally Posted by mofo989 View Post
Interesting product. It came out after I did my van. I see it is 1-1/2 thick... might work. I'd love to see a sample to understand how easily it can be folded and tucked into tight places like the Thinsulate. Thinsulate certainly is meant for acoustic damping and is intended for automotive, so it does have that going for it.
I'm already committed to Thinsulate (about 50% installed with the rest to be finished next week) but I'll seriously consider the Thermwrap to fill out the lower walls, sliding door and other areas which the Thinsulate didn't fully fill.

It looks like it should be as easily manipulated as the Thinsulate, though the Tyvek will be a little stiffer than the black polyester scrim on the Thinsulate, which might be a good thing.
Inertiaman is offline   Reply With Quote
Old 10-09-2015, 05:17 AM   #19
mofo989
 
Join Date: Sep 2012
Posts: 466
Thanks: 33
Thanked 88 Times in 64 Posts
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

Yeah, a more durable scrim would be a nice benefit. I think you're onto something here! Too many people stick with the same old methods and technology... even RV up fitters using fiberglass... yuck.
mofo989 is offline   Reply With Quote
Old 08-22-2016, 03:12 AM   #20
SprintingDragon
 
Join Date: Aug 2016
Posts: 4
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Using Reflectix / Rattletrap Incorrectly? - I am rethinking my insulation approac

Quote:
Originally Posted by mountainhick View Post
Rattle trap etc is Constrained layer Damping material. Look up sound deadener showdown and read his info about CLD. I think many people use it incorrectly. It is not a sound barrier, It is a damper that changes the resonance of vibrating panels. It can be used judiciously in small quantities with great benefit, but you reach apoint of diminishing returns if you over do it. Covering every inch of your van is not cost effective use of the material.

I used CLD in my previous van and just applied most of it in our Sprinter yesterday. It may be moot if you stuff walls with batt insulation, the batt will also dampen vibration, but I noticed a beneficial difference when I added CLD to the Previa after driving it for a while with just polyester insulation in the walls.

I just had a thread about reflectix. Yes, you need an airspace for it to be effective as a radiant barrier. If you can furr it out from your walls and provide an airspace, it will help reflect heat back to the shell rather than allow it into the interior. Call them!
When you say 'judiciously', do you have any pointers on what would that be? As a dampener, would it work better cut into strips with open metal in between? Or around the edge of the space, or completely covering 'noisy' places like the wheel wells?
SprintingDragon is offline   Reply With Quote
The Following User Says Thank You to SprintingDragon For This Useful Post:
cwichman (06-23-2017)
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT. The time now is 01:44 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.