Skylight vent condensation

[FishinFools]

Anyone else have a simple, plastic crank up ceiling vent in their trailer/fish house?  I converted an enclosed cargo trailer this summer, and have finally had a chance to use it in cold weather.  As expected, the inside surface of the plastic vent cover frosts up when the trailer cools down after heated use.  Then the next time you heat up the trailer, the dripping starts.  I can deal with that, but the way the gasket works with the roof vent, I'm sure that some of this moisture is making its way into my wood ceiling material.

So, if you have had the same experience, what have you done to prevent the issue from occurring?  I could easily seal the entire roof vent assembly for the ice fishing season, and remove the seal for summer camping air movement.  But if you have any other ideas, I'd like to hear them.

[Bobby Bass]

Just putting a film of plastic as a barrier I  think would work. One of those plastic window kits.  Easy to install and easy to replace for a few pennies if you needed to use the vent. You just need some kind of barrierr to stop the heated air from making contact with the cold surface.

[RebelSS]

You need air movement...it helps. Couple fans mounted up in corners will help, as will a piece of insulation tucked into or over the vent "cavity". Condensation forms because that thin plastic surface is much colder than the surrounding moisture filled air. 

[FishinFools]

Just putting a film of plastic as a barrier I  think would work. One of those plastic window kits.  Easy to install and easy to replace for a few pennies if you needed to use the vent. You just need some kind of barrierr to stop the heated air from making contact with the cold surface.

Thanks all for the feedback.  I think I'll try the window seal plastic as you suggest.  I might open the vent, go on top of the roof and compress a layer of the sheet in the vent.  I might even put a marble on top of the plastic, thinking that it will roll to the center and create a low spot for condensation to gather...right in the middle of the plastic, not on the edge which could increase moisture into the wood surround. Then, I'll put a second layer using the double sided tape inside the trailer in an attempt to completely seal the opening and create a multi-pane solution.  

[rustysetter]

Thanks all for the feedback.  I think I'll try the window seal plastic as you suggest.  I might open the vent, go on top of the roof and compress a layer of the sheet in the vent.  I might even put a marble on top of the plastic, thinking that it will roll to the center and create a low spot for condensation to gather...right in the middle of the plastic, not on the edge which could increase moisture into the wood surround. Then, I'll put a second layer using the double sided tape inside the trailer in an attempt to completely seal the opening and create a multi-pane solution.  

check with an rv dealer they make insulation kits specific to those vents unless want it open for the light it provides at least during the day.

[FishinFools]

I did put some 3M window seal plastic on the vent and it sealed up well.  We were out for a few nights on Upper Red last week and I did not see any moisture above (inside) the 3M plastic.  Easy fix!