Building an Arctic - Cold Weather Pack

[Ronin]

You do not want to use spaceloft or any of the other aerogel insulations! They are essential a fiberglass batt, impregnated with an aerogel dust which gets everywhere and is horrible to work with, requiring gloves and dustmask. The batts are fairly stiff and would not work well for this application. I use this stuff for some very specific applications in a high altitude research project, and while it does work well, it is really unpleasant to be around unless it is fully encapsulated.

Also, consider the thermal loss out of the rest of the camper - there is no point insulating the soft sides more than the rest of the camper. I think the walls and roof of the camper have 1" foam insulation, but you need to add the conduction path through the frame, single pane windows and roof vents to the calculation, meaning the effective insulation is probably more like R-3 or R-4, so there is not much need to go above this for the soft sides. I have used 'warm window' insulation for a previous camper arctic pack, and it seemed to help a little, but did make the arctic pack more cumbersome:
https://www.fabricdepot.com/warm-window-insulated-shade

Thanks for sharing your first hand experience working with Spaceloft. Watching the attached training guide the sheets look to be flexible and neither installer is wearing gloves or face masks. Is this the same material you've worked with ? But again, as you state just throwing an insulation blanket on the soft sides will not keep the camper from heat loss. This brings me back to my original concerns of what the gain would be of having an Arctic Pack.

 

[ckent323]

Rando wrote:

"Also, consider the thermal loss out of the rest of the camper - there is no point insulating the soft sides more than the rest of the camper. I think the walls and roof of the camper have 1" foam insulation, but you need to add the conduction path through the frame, single pane windows and roof vents to the calculation, meaning the effective insulation is probably more like R-3 or R-4, so there is not much need to go above this for the soft sides."


FWIW: Based on extensive research and reading about insulating my house as well as working closely with the Thermal Engineers on Spaceborne scientific instruments for 40 years (I am a instrument Systems Engineer - mostly Opto-Mechanical) I concur with Rando's comment above.

I have not yet heard back from my colleges on Spaceloft (I am very familiar with metalized mylar multi-layer blankets but not spaceloft).

What I believe Rando was saying is that blanketing the soft sides only makes sense up to matching the R-value equivalent to the insulation in the hard sides and top (which is on the order of R-3 or R-4)

Using a better insulator with higher effective R-value in one location if you do not use it in the others doesn't really accomplish much

This brings up another issue. The lower portion of the campers is Plywood. Plywood has an R value of only about 1.25 per inch.

So the aluminum body and top may have an R-value around 3 but the soft sides and the base have an R-value around 1.

Of course putting an R-3 or R-4 liner around the soft sides in combination with the existing insulation in the Aluminum top and sides will help keep heat in around the overcab bed area even if the floor area is much colder.


The insulation in my 2007 Keystone is some kind of white Styrofoam which has an R-value around 5 per inch but, as Rando points out, the Aluminum studs and rafters in the top, walls and the glass windows brings the effective insulation down to the range of R-3 or R-4.

So all this said using a material that is more than R-3 per inch is not worth the extra expense (or trouble) unless you also upgrade the insulation in the top and sides as well as retofit double pane windows.

Regards


Craig

 

[rando]

Having spent some time working with this stuff, I always wear a dust mask and gloves. I don't think it is necessarily a health hazard, but the dust (aerogel) has an amazing propensity to dry out your skin, and make you cough like crazy if you inhale it. When you are cutting or moving it generates a lot of dust, and as it is super hydrophobic it is hard to wash off. It is plenty flexible for installation in a building, but folding up an arctic pack made of the stuff would be harder - it is like a thick felt or the double layer reflectix type insulation.

As for the insulation value - just the dead air space between the arctic pack and the vinyl wall will get you an extra insulation of R 1 or so and the surface effects and the insulation of the material itself (which is kind of fuzzy) is probably another R .5 or so. However the best indication is practical experience - the camper is much warmer (probably 10F more above ambient) with the arctic pack without the furnace running, and the furnace cycles noticeably less often with arctic pack installed. It is also more comfortable with the pack installed - you don't feel the radiative loss to the bare liner. Even at the same interior temperature, it feels warmer with the arctic pack.

 

[Ronin]

Having spent some time working with this stuff, I always wear a dust mask and gloves. I don't think it is necessarily a health hazard, but the dust (aerogel) has an amazing propensity to dry out your skin, and make you cough like crazy if you inhale it. When you are cutting or moving it generates a lot of dust, and as it is super hydrophobic it is hard to wash off. It is plenty flexible for installation in a building, but folding up an arctic pack made of the stuff would be harder - it is like a thick felt or the double layer reflectix type insulation.

As for the insulation value - just the dead air space between the arctic pack and the vinyl wall will get you an extra insulation of R 1 or so and the surface effects and the insulation of the material itself (which is kind of fuzzy) is probably another R .5 or so. However the best indication is practical experience - the camper is much warmer (probably 10F more above ambient) with the arctic pack without the furnace running, and the furnace cycles noticeably less often with arctic pack installed. It is also more comfortable with the pack installed - you don't feel the radiative loss to the bare liner. Even at the same interior temperature, it feels warmer with the arctic pack.

My idea is to just sew velcro to the leading edges of some type of flexible lightweight material to attach it over the length of the canvas. I'll want to pull the blanket off and roll or fold it up when I pull the top down. You mention warm window insulation- would a single layer of this material work?? I'm not looking for total insulation of my camper, just something that will make a noticeable difference.

 

[rando]

I would just go with the Kimberly Clark Evolution fabric that FWC and most folks here are using. It does make a noticeable difference in how warm the camper is AND you can leave it in place when you put the top down. A single layer of the warm window fabric (which is a multilayer quilted fabric itself) would maybe make a little more of a difference, but you run the risk of not being able to leave it installed. The other nice thing about the Evolution fabric is that it absorbs essentially no water so it won't get wet with condensation and it is super easy to cut and sew.

 

[buckland]

Neither my wife nor I have the sewing ability for this ...though being a self-reliant sort I sure wish I could. I absolutely cringe at the nearly $900 for the pack but ..... for those that have them are they up there in the "oh...absolutely worth it" category. (I have a few things in it).

 

[FreezingMan]

We went with the warm windows fabric for our arctic pack upgrade. In my opinion having a good vapor barrier is key if you camp in low temperatures. We still get ice at the camper ends where the fabric does not extend. Overall it’s a huge improvement over the fwc arctic pack. We had a couple times where it was it was difficult to drop the camper due to ice buildup between the liners when using the fwc pack. We added external rigid insulation around the hard sides and place removable sections over the windows. With all this we use less propane and temperature is more constant throughout the night. The coldest we’ve camped is around-20f. Starting the truck was the biggest concern.

 

[Gumbus]

Thank you FreezingMan, I tried to find original material used in the build that ski3pin used (KC - EVOLUTION / BLOCK-IT 400 SERIES 55" GRAY)but it is very difficult to find or it has been discontinued. I can acquire the Warm Windows Insulated Shade material at a local JoAnn store though somewhat pricey. Appreciate your input.

 

[Durango1]

Thank you FreezingMan, I tried to find original material used in the build that ski3pin used (KC - EVOLUTION / BLOCK-IT 400 SERIES 55" GRAY)but it is very difficult to find or it has been discontinued. I can acquire the Warm Windows Insulated Shade material at a local JoAnn store though somewhat pricey. Appreciate your input.

After doing a deep dive into Warm Company, Hobby Lobby and JoAnn I stumbled on "fusible" high loft fleece material. Basically you use a steam iron and the built in adhesive sticks it to the fabric. For those of us with an existing FWC Artic Liner I wondered if this could be used to increase (even a little bit) the thermal effectiveness of our liners... https://www.joann.com/thermolam-plus-fusible-45in-wx-15-yds-dbl-rolled/6224372.html?gclid=Cj0KCQiAwJWdBhCYARIsAJc4idCsNPVkkpHOjCyfMfn1lSQgDV_93gLL0VZ6sXKgOUf1iH5i31wP49YaAulEEALw_wcB

 

[Taku]

we used 105 gram thinsulate and layered it with a nylon taffeta coated material. folds down fine with the top down, gives good insulation and does not absorb condensation. easy to take down and clean. does take some sewing ability - or at least patience with lot's of needle to hold it together whilst sewing. think it cost about $200 all told

 

[goinoregon]

I would just go with the Kimberly Clark Evolution fabric that FWC and most folks here are using. It does make a noticeable difference in how warm the camper is AND you can leave it in place when you put the top down. A single layer of the warm window fabric (which is a multilayer quilted fabric itself) would maybe make a little more of a difference, but you run the risk of not being able to leave it installed. The other nice thing about the Evolution fabric is that it absorbs essentially no water so it won't get wet with condensation and it is super easy to cut and sew.

hi rando, any more thoughts on the evolution fabric? did u use 2 layers? (inside/outside). and are u happy with foldability?

 

[scuba6388]

I love the idea of the evolution fabric, but it seems that a breathable fabric is going to let water vapor through, and increase condensation on the liner backside.

I was looking at utilizing a 4 oz (140 D.) super K-Kote PU coated ripstop nylon on the inside and outside and 210 g. Thinsulate UDS core. I believe this would still allow leaving the liner installed, but limiting water vapor transfer behind the liner and adding actual insulation.

Anyone try anything similar? My other thought is utilizing evolution fabric inside, thinsulate core, and tafetta or ripstop nylon outside.

I bought a 2013 Hawk that was a little rough on the inside, gutted it, added 1" insulation on top of all surfaces including front wall, back wall, side walls, floor, and under the bed before completing the remodel. Coming from a Total Composite hardsided camper, I'm looking to build the best 4 season FWC I can.

 

[Vic Harder]

see my other note regarding condensation behind the liner...

 

[rando]

I love the idea of the evolution fabric, but it seems that a breathable fabric is going to let water vapor through, and increase condensation on the liner backside.

I was looking at utilizing a 4 oz (140 D.) super K-Kote PU coated ripstop nylon on the inside and outside and 210 g. Thinsulate UDS core. I believe this would still allow leaving the liner installed, but limiting water vapor transfer behind the liner and adding actual insulation.

Anyone try anything similar? My other thought is utilizing evolution fabric inside, thinsulate core, and tafetta or ripstop nylon outside.

I bought a 2013 Hawk that was a little rough on the inside, gutted it, added 1" insulation on top of all surfaces including front wall, back wall, side walls, floor, and under the bed before completing the remodel. Coming from a Total Composite hardsided camper, I'm looking to build the best 4 season FWC I can.

I would be interested to hear how this goes.

I can think of two issues you may run into - moist air will likely still make it behind the liner and condense on the vinyl, even if the liner itself is impermeable as it is not very well sealed at the lift panels or windows. Once back there, it will be much harder to dry out, and you would probably have to remove the liner to get it fully dry, which is a PITA. With the permeable liner, yes you get condensation back there, but it dries out pretty quickly on a sunny day with the fan on so it is not something we have worried about. Secondly, if it is really cold out, you will probably still get condensation on the inside of the thermal pack, which will then get on your bed when you lower the top. I guess I think of it like a traditional double wall tent - you get condensation on the fly, but the inner tent protects you from that.

On our prior camper the soft sides were gore-tex, which was the bees knees, no condensation on the soft sides, and very little elsewhere as the moisture could escape.

 

[scuba6388]

I would be interested to hear how this goes.

I can think of two issues you may run into - moist air will likely still make it behind the liner and condense on the vinyl, even if the liner itself is impermeable as it is not very well sealed at the lift panels or windows. Once back there, it will be much harder to dry out, and you would probably have to remove the liner to get it fully dry, which is a PITA. With the permeable liner, yes you get condensation back there, but it dries out pretty quickly on a sunny day with the fan on so it is not something we have worried about. Secondly, if it is really cold out, you will probably still get condensation on the inside of the thermal pack, which will then get on your bed when you lower the top. I guess I think of it like a traditional double wall tent - you get condensation on the fly, but the inner tent protects you from that.

On our prior camper the soft sides were gore-tex, which was the bees knees, no condensation on the soft sides, and very little elsewhere as the moisture could escape.

Woah, didn't know any were doing goretex. What kind of camper was that?

I was hoping to make the thermal liner sides velcro as well as the window openings. This way I would have the ability to roll up the thermal liner and dry with a towel behind it. I agree, some moisture is going to make its way back there.

Also, still trying to figure out a way to bring the liner around the lift panels. Would any material behind there inhibit the hinges from closing all the way?

My other idea is to have a fully removable insulation liner on the outside that I would take up and down, although that would be much less convenient and take more storage space. However, it would allow more insulation and a better vapor barrier.

 

[rando]

The gore-tex was on a custom UZJ100 pop top - it was awesome, but a little too cozy for 2 people during the winter.

I couldn't figure a good way to deal with the thermal pack and lift panels - you can't go behind them as the vinyl is riveted to the panels, you can't go in front because of the overlap on the panels. One option would be to stick some insulation to the panel itself, separately from the thermal pack. I ended up just tucking it a few inches behind the panel, like factory thermal pack, but the lift panels are noticeably cold and condensing.

I have seen someone who just has a ~60' piece of 24" reflectix that they wrap around the outside of the liner. Besides the pain to set it up/remove, outside insulation seems like a great option. Maybe give this a try until you figure out the best path for the thermal pack?

Honestly, these campers are never going to be great in the cold or the wind, there are leaks and thermal bridging all over the place.

 

[ski3pin]

The ski3pin are back with another cold weather pack build. With the help of my Cousin Sherry in Arizona, we built a arctic/thermal pack for our new camper. During her working years she had her own upholstery business. She still enjoys projects and offered to help put together a thermal pack for the inside of the sideliner. We had all the material and supplies on board when we left on 18 November. First stop was Cousin Sherry’s place in Oracle, Arizona.

This time we were using new material and a couple of design/build changes. Four Wheel Campers kindly agreed to sell us the new quilted material they recently switched to for their thermal packs.

I went over with Sherry the design and measurements and we put together a plan with pen and paper. Old ways still get the job done right.

With this material, edge binding is used instead of a folded hem.

The major difference in our new design was initially cutting separate panels instead of one long piece for each side. Each panel was edge bond and Velcro sewn vertically for the openings over the windows.

We hung the panels in place to check fitment. The vertical Velcro held the panels together and kept everything square.

Next up was sewing the wide Velcro along the top that adheres to the Velcro strip on the sideliner. This also joined the individual panels together.

With the Velcro in place, we checked the fit again. It was looking great.

We made the pieces that tuck behind the lift panels longer and cut slits for the straps that capture the sideliner to the back of the lift panel so the sideliner folds in when the top is lowered. The slits were hemmed.

With the panels sewn together, it was a delicate dance to keep control of the bulk as work continued to sew button holes for the D-ring loops on the sideliner windows.

It took three days to get the project completed. The result is wonderful!

All of us are work/project oriented – instead of sitting on our butts and “visiting,” so this project made for a great get together for all of us.