Food storage area in basement

[John Gregory]

Last night my wife and I toured our DIL’s new home. Under the front porch is a food storage area. About 8’X 8’ all of the walls are concrete foundation, and a metal ceiling that has the porch concrete poured over it. The room is on the north side of the house. We have had below average temps in Utah this winter and the room gets very very cold. There were ice crystals on the top of the concrete walls. Some items have frozen.
The problem she is having is that the warmer moist air from the home enters the room and water condenses on the metal ceiling and drips all over the place.

Would it be wise to insulate this room? Would one have to worry about the insulation getting wet from the condensation? The door to the room is just a standard passage door, probably hollow core. Any suggestions would be appreciated.

Thanks

[Jeffrey Fusaro]

john--

a couple of thoughts....

i would start on the outside of the home. it sounds like this is new construction???

i would start by backfilling some dirt or mulch (an insulator) around the patio and try to seal the patio/cellar ceiling joint to prevent air/moisture infiltration.

being that the patio floor is the ceiling of the storage area, the temperature will be tough to control, without significant amounts of insulation. like you said, it may still get moist. i'd avoid isulating that room.

i would consider replacing the access door to the room with an exterior grade, insulated door - with a weatherstrip. the thinking being - keep the heat and humidity from the basement out of the cold storage room, rather than trying to regulate the temperature inside the room.

finally, you may want to put a dehumidifier in the storage room. a second in the basement may also help.

[Jon Shively]

I was thinking of the exterior door also which might eliminate the temp difference. Also so it doesn't drip on you or the food items, the stiff plastic/foam sheets of insulation below the ceiling angled towards the walls into a trough (old eavetrough). Then, in our barn when I was a kid, in our tackroom where our pump was we would keep a 60 amp light burning until like this weather, we would put one heat bulb in, but we wanted to keep it well above freezing (in the 45 degree range). So a single light bulb might keep it warmer and drier for her. Just a thought.

[Art Mulder]

It's a balancing act, John. I agree that you should insulate the door -- I grew up with a "fruit cellar" in our basement, also under the front entrance. My dad had stapled 4" paper-faced insulation onto the old single-plank door, to help it stay cool in the summer. It had a small vent up near the ceiling as well.

But in this case, John, it seems to me that if you insulate the door, this is just going to make the room that much more likely to freeze, which is not the idea. Yes, insulate the door, but I think you also want a bit of air movement, don't you? That is to keep it above freezing.

[Ben Grunow]

Ditto what Jeff said except that I might try to add a couple layers of rigid foam insualtion to the ceiling (assuming the patio is on grade with just this small closet below) to attempt to seal off the cold. Cut to fit very carefully and secure with wedges of rigid foam so if the whole thing goes bad you can just remove it.

Dehumidifier and draft elimination/insulation are important.

Good luck.

[Frank Chaffee]

John,
I would insulate the ceiling and the walls to below frost line. The condensation results from warmer, moisture laden air coming in contact with cold surfaces. The relatively cold or very cool conditions that exist on the steel ceiling and upper walls are a perfect formula for condensing moisture from interior air.

Seal the door to prevent air exchange. I would insulate the door as well, because that will keep the storage room cooler in the summer.

If the upper part of the room is insulated, a surprisingly small light bulb will prevent freezing.