Condensation between tent floor and pad when sleeping on snow

If there is a trick, let me know too. Comes with the territory. I usually only spend one night out on snow, but have done 3 nights in the Spring. A ground cloth will help.
Duane

Finding water under the mats when camping on snow is absolutely normal. And absolutely unvoidable too.

Think about it. The snow under the groundsheet is at -10 C (for example). The groundsheet will be at about the same temperature where it touches the snow. You are inside the tent breathing out moist air with every breath. Some of that moist air gets near the groundsheet and the water vapour condenses out onto the groundsheet – and slides underneath out of the way. Preventing this is almost impossible: it's basic physics.

You can reduce the amount of condensation by coving the floor with your mat, your quilt, your gear, your food … etc. Anything which insulates. That way the really cold surface of the groundsheet is covered and not attracting moist air. A little through-ventilation also helps: it sweeps the warm moist air out of the tent.

Cheers

It doesn't hurt anything.

–B.G.–

For winter camping trips, (if I can afford to carry it) I bring a lightweight cheapo foam pad that I use in lieu of a tent groundsheet, and install it under the floor of the tent.

I find that this setup typically allows "most" of the ground contact condensation to occur between the tent floor and the exterior ground pad (depending on the temps, of course.) I used to use some old snap-together foam kiddie pads (http://www.greatmats.com/interlocking-floor-mats.php), but have been using Reflectix for the past two winters (due to an over-abundance of it from work.) Reflectix is nice because it can be easily cut to fit a tent floor, and becomes a very good sled for the kids.

About a month ago when camping on snowpack in 15d weather, this method worked very well. The floor of my tent under my pad was cold, but not wet at all. When taking the tent down, the underside of the tent floor (and exterior Reflectix) was sopping wet.