I know this topic has been beaten to death already but I can use your expertise. So currently I have a set up where I store most of my wines off-site. I have two medium size built-in wine fridges for short term storage. The off-site unit is about an hour drive so one of the fridges is pretty much dedicated for overflow storage until I get a chance to drop off at the storage.
I’m considering turning NE corner of my crawl space into passive storage. This would be for sub $50 daily drinkers that will be consumed in the next 3-5 years.
I’ve been monitoring the temps for a week or so. It ranges from 69 to 72 degrees with Rh around 85%. Daily temp fluctuation is less than 1 degree. I’m not worried about the labels so Rh is not a concern but 72 degrees does concern me. The outside temps are now close to 90s and this weekend it’s supposed to hit 97 which I hope would be the hottest day of the year.
My question is how hot is too hot for a passive cellar? Do I need to consider adding an AC unit?
The crawl space is around 2500 SY so unless I partition off a section AC unit may not be practical.
The NE corner is 8 by 10 and 5 ft tall and doesn’t receive any sun. Foundation walls are concrete cinder blocks and 1/3 under ground. I’m in central VA.
I appreciate everyones input.
As long as the temperature remains under 78 degrees Fahrenheit (26 degrees Celsius), then there shouldn’t be any risk for heat damage.
Seasonal swings in temperature are not concerning either.
Higher average temperature results in the wine maturing sooner, lower temperatures in maturing later.
There should be no noticeable difference in wines to be drunk within a few years as opposed to wines drunk within a few decades.
I’ve stored in much worse when I was younger without serious issues. You should be fine for the 3-5 years storage. But if you want to section off a smaller section and insulate it, I’m willing to bet you can drop the high temp by a few degrees. I noticed a drop when I finished off my NE corner in my basement.
For 3-5 years I wouldn’t be concerned at all between 69-72 if it were me. Worst case scenario if they aged for more than 3-5 years is that they would develop faster than the wines in your fridge and offsite in the same time frame.
If you wanted to get more utility out of the space (assuming it’s in your basement), you could consider insulating the walls and ceiling with rigid and see if you get more stable and lower temps.
So just to experiment, I bought a small foam cooler and added extra 1” styrofoam inside. That should give me about R10. I’ll monitor the temps for a couple of days see if that makes a difference.
For reference, I am in NJ and have a basement approx 5 foot under ground. My cellar is passive and insulated with the walls and ceiling with rigid R-15. The attached picture is my FLO app and the 7 day average humidity and temp.
This screenshot is the uninsulated utility room adjacent to my wine cellar (cinder block and concrete slab). Hopefully this gives you some idea of the expected gain from the insulation. Obviously the higher R value the better result.
No problem at all for daily drinkers, especially if they will be consumed over the next 5 years or so. I keep most of my daily drinkers at room temp (85 and higher) and I never had a problem with cooked wine.
Curious - can you just affix rigid insulation board to concrete slab?
I have a small passive cellar area in the corner of the basement. I’d love to just paint the exterior concrete with insulating paint and slap some foam board on the inside and call it a day.
The important thing here is daily drinkers and 3-5 yrs so yes that is fine. If it were long term storage and pricey wines I would so no that is not good enough but of course others will disagree on that point.
Like others mentioned, for 3-5yrs would be fine. I had similar summer temps in the passive storage of my old house. You can keep the “nicer” daily drinkers closer to the ground to shave off a couple more degrees too.
Relatively small sample size but I found after 6 years or so there was a drop off but depended on type of wine as well.
You can glue the rigid on to cinder block and concrete. You can start by cutting the ceiling portion to size and glueing. Then when you adhere the insulation to the walls it also helps prop the ceiling pieces up. I’ve had it this way for about 4 years now and have had any issues with the insulation moving.
I also painted right on the insulation in a ceiling white color to cut down on costs. You can barely tell it’s insulation, looks more like a regular sheetrock wall.
If the wines are stored densely stacked in cases the overall mass of the wines will dampen down day to day fluctuations in temperature, especially for those in the middle or base.
I drylocked the cinderblock before I installed insulation. The insulation I used is moisture retardant so wasn’t concerned about mold. It’s not risky like using the batt insulation.
Super helpful thank you! I have a contractor that can do the framing, insulation and drywalls. I just have to do the math see if it’s worth it. I don’t think it’d add much value to the house in case I decide to sell. I may be better off putting the money towards a wall cellar.
Now if I had the funding I’d add a floor access from the dining hall just like they do with the spiral cellars. That’d look neat.
In my example I had masonry on the walls, ceiling (poured concrete) and floor. So I had no considerations for floor joists etc.
I don’t have a construction background but I have to imagine floor joists and things like that are pressure treated and wouldn’t rot or be effected by any percentage of relative humidity.
You can save a lot by skipping the sheetrock and only putting up rigid insulation and painting it. My cellar looks fine and I saved a ton in contractor costs doing it that way.
