So yeah, as the title says, this is a step by step on how to make condensation free storm windows for your RV / Camper / Van / Shell / whatever. This is the 3rd RV I have made these for, it works.
I debated putting this into the running RV thread on the main page but concluded it might stand alone as a search provided no hits for this topic. There has been much discussion on what to use but I have never seen the actual "how" addressed, which I believe is more important. If you have air leakage, the window and/or frame will sweat. The following is how to prevent that.
What you will need:
The Velcro was $86 with free shipping, the Reflectix and Vinyl was about $45, so $130 in total materials.
I went with 2 different materials, as I was only concerned with light transmission for a few of the 7 windows and 3 skylight/vents I was working with. For around the bed I went with Reflectix for the additional thermal properties. To be honest, I don't think there is really that big of a difference between the 2, but in a ski area parking lot, I'll take the black-out version for this application. I used 10 linear feet of this stuff:
For the windows and skylights/vents I wanted to see out of, I went with 8mm Vinyl. Both products were sourced from the local hardware store. I used the top one, the middle is 4mm and too flimsy if you plan to remove them in warmer weather as it stretches very easily. The 4mm is also not as clear as the 8mm. I used 10 linear feet of this stuff too:
Vinyl comes with tissue paper so it doesn't stick to itself on the giant roll.
Its quite clear, not too wavy/grainy.
The other items you will need are pictured below. As I plan to remove them every summer, I am using 1" Velcro, in hindsight I could have used 3/4". For anyone making a more permanent install, simple double-sided tape with the foam layer will suffice. About the Velcro, when buying bulk you have the option of 5 different adhesives and can mix and match, which is what I did. I ordered 28 yards (yes, 84 FEET of Velcro), it is the most expensive part of this project. I found the best price online from the iTape store, no affiliation, located in NJ. The Loop side is Adhesive #19 (general purpose not rubber based), the Hook side is #75 (specifically for vinyl).
Its best to pre-assemble your Velcro, this method works well. By keeping the spools on their sides, the edges line up nicely, just keep everything on the carpet/floor.
It helps if you have someone to hold the wheels to provide some tension, or place the legs of a folding chair through the hubs. It is very important to pinch the layers together tightly, wavy sections will be a mess later in the process.
Once you have all the Velcro matched, disassemble one of the hubs and restart the spool like this.
Then reassemble so you can wind everything back up
From this mess
to this.
After squaring up the cut ends of the vinyl and measuring the lengths needed, I again used the square as a fence, rather than mark lines with the Sharpie. I used the Sharpies on the Reflectix as it was easy to hide the marker residue on the back side the Velcro attached to. I used the 6' square as my straight edge, as I was using 48" material and my longest run was 64"
The Velcro has 1-1/4' clear backing on the adhesive side, making it very easy to line up with the edge of your panel, just slide your thumb along as you go. I always attach the "hook" side of the Velcro to the covering, which leaves the fuzzy "loop" side on the wall in the summer. I also prefer to only expose a small amount of adhesive as I go, YMMV.
Performance of the window covering will be determined by how good you can make the corners. Try to trim to fit like this. I should also note here why I had 2 pair of Fiskar's in the supplies picture. The adhesive is insanely sticky, unless you cut all your covers first, then cut Velcro, you will be cursing said adhesive when trying to cut more cover material. It was very easy to get a "run" started with clean scissors without snipping, in both the vinyl and the Reflectix. With gummed- up scissors, not so much.
Peel back the backing and snug up the seam as tight as possible.
This may sound overly OCD, but any gaps here will let air move, causing condensation to form on the windows. Your corners should look like this.
This is a pile of covers, mid-production its time to take this to the driveway.
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