Redfish
Advanced Member
Late to the party here, but another option is a product called Marine Hypervent (or similar products) http://www.hyperventmarine.com/products.html.
Very lightweight, 3/4" thick. Hypervent is recommended in many RV and marine forums and is what I use. It's a bit expensive, about a $80-90 to cover the over-cab portion of my Fleet bed. It not only provides excellent ventilation but significantly increased the warmth of the cab-over part of the mattress. When it's time to collapse the bed, I just reach under the middle of the mattress with one hand and lift the Hypervent slightly while pushing on the extension, and the entire Hypervent sheet rides up and over the lip with very little effort. When the bed is collapsed, the mattress sits on top of the Hypervent. When I store the camper, I don't remove the mattress, but rather pull the bed extension out 6 inches and center the mattress so that air can circulate under the north and south sides of the mattress.
From the manufacturer: "HyperVent is a special material that consists of a white spun polymer woven into a large open configuration that is bonded to a breathable white fabric layer. This light mesh of polymer does not compress, allowing an open layer of air to form. It is 3/4" thick, allowing plenty of dry air to circulate. This material is lightweight and flexible, yet rigid enough to hold its shape indefinitely. The texture of HyperVent can not be felt even through the thinnest of mattresses!"
Hypervent (and similar products) come in a 39" width, so you'll need to order enough to attach two pieces to cover the entire cabover area, which means you'll have to order more than you need, attach two pieces together, and trim to size. It's easy to attach 2 pieces using the provided 3" flap on the cover material and hot glue. Or you could order it custom-made to size here: https://www.mattressinsider.com/mattress-condensation-prevention.html. I'm sure you can find it cheaper, by searching the internet of if you live in an area with lots of sailboats and cruisers.
I live in north central Florida, which sits right on the border between temperate and sub-tropical climate zones. My camper is on the truck and mostly out West from spring through fall. When stored for the winter here in Florida, my camper is on a dolly in a carport. From November-March, we experience weekly rapid changes in temperature and absolute humidity with each passing front, which leads to significant condensation when warm humid air comes in contact with metal or any other dense material that takes a while to warm up. I run a dehumidifier 1-2 times per month or more often if I'm in and out of the camper for whatever reason during one of the cold-and-dry-air-to-warm-and-humid-air transitions. If I'm away from home for a while, I'll use Eva-Dry renewable canisters. So far, I haven't had a hint of mold or mildew.
I also think keeping the camper under a roof dampens the temperature swings inside the camper because it reduces the super-cooling that occurs on cold, clear nights, and thus moderates the potential for condensation. I purposefully do not vent the camper while in storage, because I want to keep the air inside the camper relatively drier than the air outside the camper.
While I don't remove the mattress (at least, thus far), I do remove the cushions and anything that might absorb water (sheets, sleeping bags, books, food, clothing). I also remove any fluids in bottles or cans (e.g., wine, beer) that can create a condensation surface because they warm slowly compared to our rapid changes in absolute humidity. I pack very simply, using storage boxes or duffles, so unloading the camper is quick, easy and painless, and requires little thought or effort when it's time to repack.
Hope this helps!
Very lightweight, 3/4" thick. Hypervent is recommended in many RV and marine forums and is what I use. It's a bit expensive, about a $80-90 to cover the over-cab portion of my Fleet bed. It not only provides excellent ventilation but significantly increased the warmth of the cab-over part of the mattress. When it's time to collapse the bed, I just reach under the middle of the mattress with one hand and lift the Hypervent slightly while pushing on the extension, and the entire Hypervent sheet rides up and over the lip with very little effort. When the bed is collapsed, the mattress sits on top of the Hypervent. When I store the camper, I don't remove the mattress, but rather pull the bed extension out 6 inches and center the mattress so that air can circulate under the north and south sides of the mattress.
From the manufacturer: "HyperVent is a special material that consists of a white spun polymer woven into a large open configuration that is bonded to a breathable white fabric layer. This light mesh of polymer does not compress, allowing an open layer of air to form. It is 3/4" thick, allowing plenty of dry air to circulate. This material is lightweight and flexible, yet rigid enough to hold its shape indefinitely. The texture of HyperVent can not be felt even through the thinnest of mattresses!"
Hypervent (and similar products) come in a 39" width, so you'll need to order enough to attach two pieces to cover the entire cabover area, which means you'll have to order more than you need, attach two pieces together, and trim to size. It's easy to attach 2 pieces using the provided 3" flap on the cover material and hot glue. Or you could order it custom-made to size here: https://www.mattressinsider.com/mattress-condensation-prevention.html. I'm sure you can find it cheaper, by searching the internet of if you live in an area with lots of sailboats and cruisers.
I live in north central Florida, which sits right on the border between temperate and sub-tropical climate zones. My camper is on the truck and mostly out West from spring through fall. When stored for the winter here in Florida, my camper is on a dolly in a carport. From November-March, we experience weekly rapid changes in temperature and absolute humidity with each passing front, which leads to significant condensation when warm humid air comes in contact with metal or any other dense material that takes a while to warm up. I run a dehumidifier 1-2 times per month or more often if I'm in and out of the camper for whatever reason during one of the cold-and-dry-air-to-warm-and-humid-air transitions. If I'm away from home for a while, I'll use Eva-Dry renewable canisters. So far, I haven't had a hint of mold or mildew.
I also think keeping the camper under a roof dampens the temperature swings inside the camper because it reduces the super-cooling that occurs on cold, clear nights, and thus moderates the potential for condensation. I purposefully do not vent the camper while in storage, because I want to keep the air inside the camper relatively drier than the air outside the camper.
While I don't remove the mattress (at least, thus far), I do remove the cushions and anything that might absorb water (sheets, sleeping bags, books, food, clothing). I also remove any fluids in bottles or cans (e.g., wine, beer) that can create a condensation surface because they warm slowly compared to our rapid changes in absolute humidity. I pack very simply, using storage boxes or duffles, so unloading the camper is quick, easy and painless, and requires little thought or effort when it's time to repack.
Hope this helps!
