[slow3door]

I am looking to insulate for 4 season use in Maine and wanted to get some feedback on using DRI-CORE R+ Insulated Subfloor Panels. I have only seen this used in a bus conversion in Canada and was unable to find anything in the forums, so I thought I would check before getting started.

1. Is this a smart choice for a subfloor?
2. If this is a solid idea should I leave it floating as it was designed to be installed or use PL90 to adhere the XPS to the van floor and/or in the tongue and groove to prevent movement ?
3. I am also considering using an additional 1/2" of XPS adhered to the metal floor and then installing DRICORE on top of that for an increased R-value of 2 or 3? (1/2" XPS = R-3 and 1" XPS = R5 but not sure if 2x 1/2" XPS panels combined would be R-5 or R-6?

What made me look at these panels:

• They come pre-insulated -made of 1/2" of OSB with 1/2" of R-3 XP glued to the bottom with air flow channels.
• Easy to work with 2'x 2' panels that lock together without the need for adhesive
• They were developed to insulate damp/wet concrete floors to insulate and the Air Gap Technology helps protect against moisture, mold, mildew and small water leaks.

Thanks for any advice!

Dricore R+ panel image

Bus install pic I found

 

[kenryan]

My only advice is to insulate to the highest R value that you can reasonably justify. For a 4 season camper in a cold climate, nothing is more important than insulation.

 

[slow3door]

My only advice is to insulate to the highest R value that you can reasonably justify. For a 4 season camper in a cold climate, nothing is more important than insulation.

Agreed! Also have the medium roof so looking to keep 5'9" ceiling height after insulation, floor and ceiling are installed.

 

[kenryan]

Agreed! Also have the medium roof so looking to keep 5'9" ceiling height after insulation, floor and ceiling are installed.

If you are short on headroom but want to maximize R value, the solution is to use the insulation with the highest R value per inch. I don't know of anything that beats sprayed urethane for such an application.

Also, using the thinnest sheathing that will do the job will allow for thicker insulation.

 

[slow3door]

If you are short on headroom but want to maximize R value, the solution is to use the insulation with the highest R value per inch. I don't know of anything that beats sprayed urethane for such an application.

Also, using the thinnest sheathing that will do the job will allow for thicker insulation.

Great point! I was looking at using VIP (Vacuum Insulated Panels) in the ceiling and large wall gaps. As long as they don't get punctured the are R-60 per inch. Best insulator I have been able to find. Again I haven't found many examples of people using these but can't see a downside other than cost.

 

[Xprmntl]

Might want to consider insulation boards or insulated sheathing boards, and ones referred to as insulated nail base for roofs. These are analogous to what you propose but there are options out there that come in bigger formats, generally the standard 4x8' sheets, and in 1" - 6" thickness depending on the insulation value and OSB thickness one wants. Huber Zip is a good one. ZIP System® Insulated R-Sheathing | Huber Engineered Woods (huberwood.com). Others are Rmax Nailable Base-3, Isolofoam Isobrace, and GAF Thermacal (even has interlocking edges) or if one prefers EPS insulation then Insullam.

 

[slow3door]

Might want to consider insulation boards or insulated sheathing boards, and ones referred to as insulated nail base for roofs. These are analogous to what you propose but there are options out there that come in bigger formats, generally the standard 4x8' sheets, and in 1" - 6" thickness depending on the insulation value and OSB thickness one wants. There are quite a few options out there, but Huber Zip is a good one. ZIP System® Insulated R-Sheathing | Huber Engineered Woods (huberwood.com). Others are Rmax Nailable Base-3, Isolofoam Isobrace, and GAF Thermacal (even has interlocking edges) or if one prefers EPS insulation then Insullam.

Yeah that's what AVC Rig uses for their $1500 floor system. Not a bad idea at all Transit 148 Insulated Flooring System — AVC RIG

 

[Captadv]

I was looking at using VIP (Vacuum Insulated Panels) in the ceiling and large wall gaps. As long as they don't get punctured the are R-60 per inch. Best insulator I have been able to find. Again I haven't found many examples of people using these but can't see a downside other than cost.

I'm curious where you've found these and what the pricing looked like. Can you share a link?

 

[slow3door]

I'm curious where you've found these and what the pricing looked like. Can you share a link?

I reached out to a pro free skier in Europe that used them in his overland rig box truck style so a much easier and better application for these rigid panels. He got them from va-Q-tec | Your expert in high performance thermal insulation . He told me that they are more expensive than rigid insulation but the performance is unmatched. He travels all over to the coldest climates so I would trust his feedback. I have tried to call Va-Q-Tec but their US division doesn't answer and their VM is full.


I also reached out to a US based VIP manufacturer and spoke to the owner of Thermal Visions is a world leader in research, development, and production of Vacuum Insulation Panels (VIP). ....(super informative but outdated website) he was a very nice guy but due to demand and not enough labor they are so backed up he couldn't make them for me. He said there are only a couple US manufacturers and they are all in the same boat. So that is what led me to find what was pre-made and available on ebay. I found some similar panels that are made by Kevothermal and appear to be manufactured in the US. The price ranges from $30-$50 per panel. There are many different sizes and the company can make custom sized panels. Kevothermal CR12AVP1EC R-A Vacuum Insulation Panel 321 mm X 321 mm | eBay

Good panel example - should be very wrinkled . If not the seal has leaked and the panel won't work as it should

below is a bad example but also for sale by the same company on ebay. There should be zero air inside the panel so be sure that is what you are getting.

Side topic, but another use I am considering is using these in a box around my refrigerator. They are already used in very high end appliances and for shipping cold freight so it seems to be a no brainer there.

 

[Xprmntl]

I'm curious where you've found these and what the pricing looked like. Can you share a link?

Google is your friend. Searching for "vacuum insulated panel" leads to quite a few hits. For instance, this E-bay listing for R-60/in Panasonic panel that is 1/2" thick (so ~R-30) sheet at ~20" x ~20" which is priced at $13, : Panasonic U-Vacua Vacuum Insulation Panels New - R rating R60 $12.99 ea | eBay This pricing seems quite low compared to what Digikey is selling them, but still 2-4X less per square foot than the price of Kevothermal that @slow3door references, ~ $53 for 1" thick 24" x 24" panel TZB7840E Panasonic Industrial Devices - FBD | Hardware, Fasteners, Accessories | DigiKey.

Upon further reading, I found that the thermal conductivity [R60/in ~0.004 W/(m•K)] of the vacuum panels is a measurement taken at the center of the panel, but due to bridging at the edges, a panel system achieves more like 0.006-0.008 W/(m•K) or R30-R40/in for relatively large panels >2ft x 2ft--Panasonic rates their 1" thick 2ft x 2ft panel at R32 and only R20 for the 1ft x 1ft. Panasonic-U-VACUA-Series-Chart-large.jpg (800×733) (digikey.com). It is also not clear to me as to whether the panels need an air space on at least one side to act as a radiative loss prevention to achieve the published R-Values? I also saw that some panels could be bent for curved applications without detriment to they're insulative properties.

 

[1x1_Speed_Craig]

I'd personally avoid using any OSB-based products, including DRI-CORE and the Zip System stuff (unless you correctly apply the Zip Tape or Liquid Flash to them). I'm using Zip sheathing for my current house build, and I temporarily used a couple sheets on an open trailer for decking. After one day of rain, but quickly drying out, the edges swelled a fair amount.

Realistically, your van will take on water at some point...opening a door in a downpour, spilling a glass of water, etc. The OSB will drink it up, despite the resins/waxes in the product.

Craig

 

[Xprmntl]

I'd personally avoid using any OSB-based products, including DRI-CORE and the Zip System stuff (unless you correctly apply the Zip Tape or Liquid Flash to them). I'm using Zip sheathing for my current house build, and I temporarily used a couple sheets on an open trailer for decking. After one day of rain, but quickly drying out, the edges swelled a fair amount.

Realistically, your van will take on water at some point...opening a door in a downpour, spilling a glass of water, etc. The OSB will drink it up, despite the resins/waxes in the product.

Craig

I'm still deciding on the floor substrate, but if I go OSB, I'm planning on just some liquid flashing for raw edges and do the perimeter with some polyethylene caulk backer rod or a rubber cord (like EPDM or neoprene) product, and maybe caulk. Probably no need for joint tape as I'll use a one piece vinyl or Marmoleum to cover. I was even thinking of "tubbing" the floor if I go with vinyl--just run it up the walls an inch or two and go over it with the wall panels.

 

[slow3door]

Google is your friend. Searching for "vacuum insulated panel" leads to quite a few hits. For instance, this E-bay listing for R-60/in Panasonic panel that is 1/2" thick (so ~R-30) sheet at ~20" x ~20" which is priced at $13, : Panasonic U-Vacua Vacuum Insulation Panels New - R rating R60 $12.99 ea | eBay This pricing seems quite low compared to what Digikey is selling them, but still 2-4X less per square foot than the price of Kevothermal that @slow3door references, ~ $53 for 1" thick 24" x 24" panel TZB7840E Panasonic Industrial Devices - FBD | Hardware, Fasteners, Accessories | DigiKey.

Upon further reading, I found that the thermal conductivity [R60/in ~0.004 W/(m•K)] of the vacuum panels is a measurement taken at the center of the panel, but due to bridging at the edges, a panel system achieves more like 0.006-0.008 W/(m•K) or R30-R40/in for relatively large panels >2ft x 2ft--Panasonic rates their 1" thick 2ft x 2ft panel at R32 and only R20 for the 1ft x 1ft. Panasonic-U-VACUA-Series-Chart-large.jpg (800×733) (digikey.com). It is also not clear to me as to whether the panels need an air space on at least one side to act as a radiative loss prevention to achieve the published R-Values? I also saw that some panels could be bent for curved applications without detriment to they're insulative properties.

Good finds! I also saw the Panasonic panels and they look like a great deal compared to the others but definitely fragile from the tests that I read. Interesting about bending the panels though I had not seen that.

The bridging on the edges is definitely the weak point on these panels and some panels are made better than others. The way that they manufacturer seals the edges seems to be the key to a good panel and what will cause the drop in thermal resistance at the edges if not done well. The panels need to be able to have almost no gap between them to avoid bridging (similar to any rigid insulation). From my research an air gap is not required but they seem to use gaps as a measure of protecting the panel from punctures in construction. In one study in Alaska they were able to get R-90 per inch as it got colder and one of the tests they did used an external , but they recommend protecting the panel with another layer to avoid puncture Panasonic says to use protective layers - Such as placing between other insulation types, air barriers, or sheathing - Fill in any gaps with cut-able insulation materials - Alternating layer seams can help reduce thermal bridging.


Here is an interview about that study

Here is the data from the study http://cchrc.org/media/VIPs_Report.pdf

Some takeaways from that study for working with these panels.

• Have a plan...Don't install anywhere you might later use a screw or something sharp that could cause a puncture
• Installation you should use 3M 90 spray or ECHO tape DC‐R218A
• Use rigid foam board to fill any gaps and use spray foam to create air sealed joints between panels
• Protect the panels with another layer whenever possible.

 

[slow3door]

I'd personally avoid using any OSB-based products, including DRI-CORE and the Zip System stuff (unless you correctly apply the Zip Tape or Liquid Flash to them). I'm using Zip sheathing for my current house build, and I temporarily used a couple sheets on an open trailer for decking. After one day of rain, but quickly drying out, the edges swelled a fair amount.

Realistically, your van will take on water at some point...opening a door in a downpour, spilling a glass of water, etc. The OSB will drink it up, despite the resins/waxes in the product.

Craig

Thanks Craig! I am going to rethink this and probably make a floor using baltic birch or advantech to avoid edge swelling from inevitable water issues. Dri-core has a ton of edges and liquid flashing the whole floor seems like way too much work

 

[slow3door]

-

 

[slow3door]

I'm still deciding on the floor substrate, but if I go OSB, I'm planning on just some liquid flashing for raw edges and do the perimeter with some polyethylene caulk backer rod or a rubber cord (like EPDM or neoprene) product, and maybe caulk. Probably no need for joint tape as I'll use a one piece vinyl or Marmoleum to cover. I was even thinking of "tubbing" the floor if I go with vinyl--just run it up the walls an inch or two and go over it with the wall panels.

I like the idea of tubbing the floor. I would definitely watch the 3 videos that Seven O Savage on YouTube. He had to rip up his subfloor and vinyl one piece floor multiple times. I thought it was pretty helpful info for planning my floor