One of the drawbacks of the Dormobile vent system is that it doesn’t lend itself easily to screens, which I have found to be very useful when camping in areas we have to share with our six-legged and eight-legged friends. Since the screen would block the strut mechanism that hold the vent up, it would have to be removed to open and close the vents. For a while, I toyed with the idea of a screen frame that would fit over the vents, but I didn’t want to drill any holes into the roof that weren’t there already.
I decided to use the flexible nylon screening one can find here in the US without much trouble. I also bought some 1" (25 mm) Velcro tape, which came in the same width. The hook side of the tape was fastened around the vent area with Permatex Black Adhesive Sealant product #81158) or 3M Black Super Weatherstrip Adhesive (product #08581).* They seem to be identical in their properties, and I've used them successfully as a weatherstrip adhesive. I presume that similar products are available elsewhere in the world. I should add that Velco comes in a sticky-back form, but the adhesive isn’t all that strong and I doubt that it would hold up to the rigors of use.
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| Figure 1: Velcro around vent window |
Note that there is a strip of Velcro running along the bottom of the vent area, but it’s hard to see in the picture because it’s stuck to the area below where the curve of the vent well is.
I then prepared the screening to fit the area, leaving an extra inch of border all the way around. This border was folded in to seal the edge of the screen, and secured with some double-sided tape. Then I put the pile side of the fastening tape.
As figure 1 shows, the fastening strip was taped to accomodate a screen about 18" (46 cm) by 24" (56 cm) in size. I used the pile strip for the screens themselves because I was going to sew it to the screen, and pile happens to run through my sewing machine more easily than the hook side. I sewed the tape down with a seam on each border, inside and out. The following picture shows all the edges of the screen folded in, with the Velcro applied to the top and bottom but not yet to the sides.
Over the years, I've noticed that the screens have shrunk by about 3/4" (19 mm). If I had to do it over again, I'd make the screens about 1/2" (12 mm) larger in each direction to compensate.
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| Figure 2: Cutting and hemming the screens |
The screen is then attached to the roof with the velcro once the vent is open, with the vent struts staying pretty much out of the way.
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| Figure 3: The screens deployed when the window is either open or closed |
And when it’s time to close the vent, I just peel away the part of the screen that blocks it. The struts prevent the screen from going back on, but that’s no biggie because the screen isn’t needed when the vent is closed. The last figure shows what the screen looks like when it’s in the vents-closed “travel” position.
| Figure 4: The screens partially removed to allow access to the vents |
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The screen fabric hangs down a little when the top is down, but presents no more problems than the vent struts themselves do. (Am I the only one who keeps hitting his head on them?)
*Some adhesives that I've tried without success are Weldwood Contact Cement and a double-sided tape from Loctite called “Power Grip” Both of these products failed to withstand the intense heat of many summers in California's Central Valley. If you have experience with products that might survive your particular climate, please share that information on the Dormobile forum.