Generic Reflectix insulator for penthouse top.

dbhost

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League City, Texas
Doesn't seem to matter the MFG, The double bubble variant of Reflectix and its clones where you have a layer of foil, layer of bubble wrap, another foil layer, another bubble wrap layer all seem to be rated at R8 insulation value. Not exactly residential but hear me out for a second while I work this idea out.

In high heat days / AC use, or REALLY cold nights / heater use, it would be nice to insulate the penthouse roof, and the camper windows to keep heat gain / loss to a minimum...

I have insulating front door and windshield blackout covers, and they do a REALLY good job and keeping heat loss in the winter to a minimum in the cab area, as the living space typically gets cold fastest before I kick on the heat...

I am thinking about getting a roll (need to measure the canvas area for the penthouse first), and make up insulation panels for the penthouse top, with a simply black felt backer on the inside that I can put some simple velcro tabs on to keep them together in place... As well as similar covers for the rear door windows, sliding cargo door windows, and the coach windows that Sportsmobile installed.

This would should go a long way to reducing heat gain / loss in summer / winter, so my AC or heat would not have to cycle on / off as much... Plus being able to fully black out any light escape from the van would help with privacy in camp. Particularly if I am stealth camping (with the top down of course...).

Am I right in this thought process? How much of this stuff should I get? And most importantly, how could it be stored en route as room in the van is pretty cramped to begin with...
 
We have reflectix panels that cover the side and rear windows. They do a pretty good job of keeping the heat in at night.

Using Velcro on the roof to hold the insulated panels is another story. We have had mixed results getting the sticky back Velcro to stay attached to the roof in hot weather. As the roof heats up the stick on the Velcro weakens and eventually releases. This depends partially on the weight the Velcro is holding and the temperature of the roof with the sun beating down on it.
 
The idea of the velcro is on the reflectix itself. I know the penthouse cover panels are going to be multiple pieces. I was thinking about using velcro to hold them onto each other. That begs another question though, how to keep the vertical?
 
Watching videos of Wasatch Overland installing Tufport tops, I saw them using spray glue to attach a foil-backed white insulation that was R23. Im not 100% sure, but I think it was this stuff.
 
Watching videos of Wasatch Overland installing Tufport tops, I saw them using spray glue to attach a foil-backed white insulation that was R23. Im not 100% sure, but I think it was this stuff.

Okay, R-23 "Radiant" - does NOT mean R-23 as in what is in the walls of our house. It is addressing one of three components of heat transfer - Thermal Radiation. It is doing next to nothing for the Conduction and Convection components.
 
So the fixed hi top and the penthouse top are two different situations all together...

I do not believe the fiberglass itself offers any sort of insulation beyond simply stopping heat loss by stopping wind from blowing through. Conductiont through fiberglass is actually quite good so it allows for heat loss pretty quickly...

The heavy canvas in a penthouse top, assuming it is the same weight canvas as say an old Coleman cabin tent from the 70s, has an R value of 7 itself. There will be an air gap between the canvas and any reflectix barrier which itself is a good insulator, dead air space, but not much of it so let's just assume it adds a value of R1, The double bubble foil backed insulation has an R value of 8, so we are at R16 so far... I know my penthouse top has SOMETHING insulating it because heat gain through the little piece of metal roof exposed is MUCH higher than under the Penthouse roof and that can't be just the fiberglass...

Back to the Reflectix type stuff. Apply a felt or fleece backing to it, The data is QUESTIONABLE, but I see some guides showing 1/4" felt has an R value of 4.

Some simple material overlaps / draft tube type stuff, and velcro to keep the panels together, and I should be able to manage R19 - R20 in the penthouse roof. and MAYBE R12 on the window covers.

It is far from perfect, but more than enough in such a small space to make AC / Heating much more effective.
 
My two cents dont address your question directly but from my experience, Reflectix does a much better job of keeping heat out rather than in. The windshield and side windows allow a huge amount of heat gain so i have a double layer of Reflectix covers that really help. In winter, I place form fitting pieces of poly styrene that i leave in place on the rear windows and rear side windows. One winter in Alaska i bought a 4 by 8 ft sheet of poly styrene and fit it to the roof basicly in one piece that made a noticeable difference in heat retention.
 
My two cents dont address your question directly but from my experience, Reflectix does a much better job of keeping heat out rather than in. The windshield and side windows allow a huge amount of heat gain so i have a double layer of Reflectix covers that really help. In winter, I place form fitting pieces of poly styrene that i leave in place on the rear windows and rear side windows. One winter in Alaska i bought a 4 by 8 ft sheet of poly styrene and fit it to the roof basicly in one piece that made a noticeable difference in heat retention.

I have insulating blackout shades, aftermarket from a company called Vanncamp for the windshield and front door windows. Nobody seems to make one for the sliding door window so I took the OE curtain which just snaps in and replicated it using a walmart thermal curtain fabric (Cheap way to get heavy insulating fabrics). It snaps in the OE top spots but I added lower snaps as well... My plan is 2 layers of the double bubble reflectix there, 2 layers in each coach window / day / night shade fitted window meaning the rear cargo doors as well... Insulating the glass area should stop honestly the majority of the heat leak in / out with the top down. I was in it last night with a sub freezing 100% RH and the gas heater on full blast. Took an hour to get it up to the set temp of 70 degrees, and in the cab area it was still drafty since I did not have the covers on.

At some point I am sure I will have to figure out how to drop the headliner on the penthouse top, and insulate between headliner and fiberglass as well...

My thought process, whether it is right, or wrong, is using the double bubble stuff, so foil, bubble, foil, bubble, foil. Like a big mac sort of... On the inside glue some inexpensive black felt / fleece that on the panels for the penthouse canvas, I have sewn on some hook end velcro. The idea there is to hold panel to panel, not panel to van... I sort of figured on sliding the panels between the lift bars and the canvas to hold them in place, just kind of friction fit... Maybe my thought process is off...

While the weather now is nasty cold (for where I live) my greater concern is the hot months and making sure AC doesn't have to struggle so hard to keep it comfy...

I know this much blackout coverage / insulation is going to make the inside of the van basically a darkroom... But it is kind of the best I can figure to be able to actually keep it comfy when the weather gets extreme.
 
We live in Colorado and camp in the winter regularly in order to extend our weekend ski trips. We have 4 pieces of Reflectix that are each about the length of our RB PH bed. I place them around the PH canvas, tucking them in between the PH bars and the canvas in the middle of the long side of the PH top, and then curling them around the corner where two of them meet in the middle of the short sides of the PH top. We use reinforcing bars in our 4 corners to help support the roof box and snow load, so when turning the corner, I tuck the Reflectix behind the load bars to help keep them in place. With our propane heater going during the night, it is warm enough up top, with a down comforter (Rumple) to sleep in our undies during cold winter night temps at elevations over 10k feet. While not a perfect solution the real noticeable difference is that without the insulation, the canvas is cold next to you, whereas the Reflectix is not when it is next to you. In the summer we put them up as well during the day, but we don't have an AC so it still gets warm in the van, just not as warm. I find a bigger difference in the winter for our use.

Also to note, by cutting into four pieces, we store them flat on top of the PH bed and they just get sandwiched between the PH top and the bed when pulling the top down.
 
Without insulation, I use the Velit 4KW gasoline heater, and have had it overnight lows in the 20s, using the Thermostatic mode so not sure high / medium / low etc... since it adjusts on its own, but I set the T stat to 70F and it holds temp there with the top up. I sleep with a Stansport Fleece sleeping bag and flannel sheets... I do have a Coleman 30 deg F bag I could probably keep the T stat set to 40 deg to keep my water from freezing and just use the sleeping bag and be good... It is nice however to be able to get up and use the port o potty without freezing my backside to it...
 
Watching videos of Wasatch Overland installing Tufport tops, I saw them using spray glue to attach a foil-backed white insulation that was R23. Im not 100% sure, but I think it was this stuff.

I was surfing Wasatch Overland’s website (Tuffport tops) and found info on their website that discloses they are using a product called Prodex. Here is a link to the product they are using:

https://img1.wsimg.com/blobby/go/79b949dd-e467-4dbc-aa26-c7faf7180775/10m technical data sheet .pdf
 
I wonder how rigid, or floppy that Prodex stuff is. I wonder what sort of closed cell foam they are talking about since rigid foam board tends to be closed cell...
 
I wonder how rigid, or floppy that Prodex stuff is. I wonder what sort of closed cell foam they are talking about since rigid foam board tends to be closed cell...

The link I posted shows a picture of the stuff in a roll, so safe to assume its quite flexible.

For my van’s insulation I used 3M Thinsulate SM600L, and covered that with “Low-E Reflective Insulation”, which is very similar to Reflectix, but far superior.

Low-E is made of 7/32″ closed cell foam sandwiched between two layers (front and back) of pure aluminum skin (not metalized plastic).

Low-E meets the indoor air quality standards set forth by California 01350 and is mold and mildew resistant.

Low-E is FMVSS 302 certified (federal motor vehicle safety standard).

Link to the Low-E material (Note, this place sells it, but their price is very high). If you shop around ya can get a better deal.

https://www.vanlifeoutfitters.com/s...MIstjY1ZbWiwMV_jBECB1fijekEAQYAiABEgLuJvD_BwE
 
Foil for penthouse top windows

I don't do any cold weather camping in my 2014 Ford E150 but I have found that the bubble wrap foil sheeting really helps in my "penthouse" windows during the summer. I had some scrap pieces left over from another home project and it wasn't enough to completely fill in the window openings but it still helped with keeping out sunlight. I simply slide the foil piece between the outer screen zip up inner cover. I usually only open the non-sun exposed side windows for ventilation and block off the sun side. Works great!
I'm going to switch out all this year with a foam/foil back roll product I've seen on Amz for higher R value insulation. Its apparently a 3M product made in USA, class 1 fire rating, non toxic. A 2foot wide by 20ft long roll is about $40 bucks but thats more than enough for the five window openings on my rig.
 
In summer, when camped, i have placed reflectix outside, on top of the roof in areas not shaded by the solar panels. It looks a bit silly but really knocks down the overhead heat gain.
 
@arctictraveller brought up a great point about putting a radiant / shade barrier of some sort external to prevent heating from direct sunlight...

That begs the how question...

I have seen hi top van guys with what look like flagpole holders affixed to their passengers side that hold up extending poles they pitch a shadecloth from that is guyed on on the drivers side, like a 10x20 shadecloth providing shade to the van and space next to it that is not covered by an awning...

How to accomposh the same thing with the penthouse top and is it worth it?

I know from prior experience pitching a tarp off the body of the van helps, but doesn't cover the penthouse roof and heat gain from there...

Obviously you would NOT want to do this in the winter since you WANT heat gain / retention...
 

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