Turn a crawlspace room into a passive cellar?

Hoping to find some help/advice on this topic.

Moved into a new home recently, and there’s a giant crawlspace under the house… it’s not really “crawl” since the ceilings are higher than me… so i can stand in it.
there’s a main crawlspace room with access through the outside (back of the house). the main space is connected to a smaller space (about 10 ft by 5ft ish)… there’s a door in between.
this smaller space has a door to my lower floor (ground level).

Ok… so i’m wondering, what are easy ways to see if that smaller space has consistent / suitable temperature to hold wine? It’s also unfinished, or at least it looks like unpainted wood…
i have no idea what I should do with it, but it seems like it can convert to a nice little storage space?
there’s probably way more questions, but it’s a case of I don’t know what I don’t know at this point I think :slight_smile:

edit: or if it’s the case, just tell me it’s a horrible idea, and should continue using offsite storage. :slight_smile:


I’m somewhat confused by your description of the space, excuse that please…

Is the space underground? or built into a hillside, with walkout access? Either way, the first step would be to chart the temperature over a year and see how close to ideal it is, knowing that you might tweak things somewhat by adding insulation and the like.

In Portland, most basements do a pretty good job of keeping in acceptable ranges, though each house is different. I suppose I also generally mean the homes built around 100 years ago or so, newer homes either don’t have basements or are more fully part of the conditioned air-space.

Mark - I’d be concerned about two things… temp in the summer and rain/minor flooding now. In your shoes I’d put a remote thermometer down there so you can see what the variance is. Don’t need anything fancy, just one that shows current, min and max temps. Obviously you don’t want it to drop to 15F when outside temps do but at this time of year it should passively stay in the 50s. Unless it’s insulated the temp swings wouldn’t be an issue for me - those will be helped if/when you do insulate it. For summer… Assuming insulation, t he issue is how warm it gets. Is this below grade? If it stays fairly cool you could always just guard against extremes by using a small AC unit so that if temps started to get above 65F you could cool the unit.

This winter I’d also watch for leaks, water, etc. And of course, look for signs of past water damage.

It’s ‘underground’ kind of… it’s more “ground floor”… there’s no leaking/water flooding risks… as if that room flooded, my ground floor is toast… :slight_smile: the crawlspace is ‘damp’ feeling especially these days, but definitely no water at all.

Summer heat - that’s my concern too. ok so get thermometer and measure… if it stays 50-60F consistently, then i guess we can talk about what to paint it, and what rackings to stick in there… for now temp measure is the key?


got a link for a remote thermometer you are speaking of?
when i google it, i get cooking therms, with a metal needle to stick into somewhere :smiley:

I use something like this http://www.amazon.com/Oregon-Scientific-THGR122NX-THN132N-Wireless/dp/B008THXATY/ref=sr_1_2?ie=UTF8&qid=1355957834&sr=8-2&keywords=THGR122NX_THN132N

Mine shows min and max temps that the sensor has seen since it was last reset. The idea is to stick a sensor down there and see if it ever goes out of a range you’r OK with.

Summer - Keep in mind that insulation will matter a lot as will the interface to the ground floor. If you have a thin interior door between the space and ground floor area I’d imagine it will eventually heat up like the ground floor does.

Try tiptemp.com. Several temp monitoring items avaailable.

Thank you!!

Definitely temp is the key. I took temp readings for a couple years before doing much. No fancy thermometer - I just went down and checked it every day. No idea what your flooding situation may be but it’s pretty good advice to consider it - especially after the flooding out here in NYC a little while ago.

If it’s truly in no risk of flooding and cool enough that you don’t need to add any mechanical cooling, you’re in luck.

But even if it’s relatively cool but not all that great in the summer, you can get by with mechanical cooling part of the year and maybe even use an air conditioner that you trick to drop lower than it’s supposed to, or you can get some of those wine fridges that need assembly - they’re not as pretty as the wood ones, but they’re perfectly adequate and much cheaper. Use those for your good stuff and leave the rest outside if you’re going to drink it soon.

Good luck.

I am more of the “wine is much hardier than most of us geeks think” camp, so I would guess you’ll be fine up in Seattle and below grade. Even if temps get into the mid or high 60s during the summer, that’s fine, so long as there isn’t much day-to-night and day-to-day fluctuation.

If you want to backstop that with some summertime A/C, that’s great as well, though my guess is you probably don’t need it.

This is assuming you have a regular wine collection for your consumption. If you’re storing cases of First Growths and DRC for long term investment or something, then I guess you should go all out.

Easy to do. I’ve done it twice - you should be able to research your area’s annual median ground temp at depth ( If memory serves 8ft+ down typically = yearly median air temp, any shallower allow for seasonal fluctuations) instead of wasting a year or two figuring out temps via thermometer. Use the floor to regulate temp, so you super-insulate everything except the floor and semi-insulate the floor itself( to minimize swings) and vapour barrier the room.
You mention wood, so I assume you don’t have much water ingress. Use moisture resistant insulation and materials if possible either way.
Dr. Gold’s book is perfect for your situation where you’re not looking to use a cooler.
Then a few of his theory’s and recco’s are backwards.

Just cleaned out the space… i should throw up a ‘before’ photo… :slight_smile:

Anyhow,half of the space has wood walls, half has cement. I’m reading that wine racking needs to be fastened to the wall, but if it’s cement, any ideas how they get fastened to the wall? (or are they really required to be fastened?)
The wood wall part isn’t the best locationwise, and will really only ‘develop’ that area if the first part gets filled up (perfect for an expansion tho!)


You can use any kind of shelves, etc. as long as they are stable and won’t fall over! And as long as they are strong enough to support the weight. The threat of earthquakes in some area might dictate securing the top of the rack to the wall, and even more robust design, in general, but that’s not an issue in my area of the country! If one is building a top-of-the-line “perfect” cellar, then mahogany wood is best (or some other sort that resists decay). But I have big shelves made with 3/4" plywood (exterior grade would be best), supported by 2x6’s, and I store cases there. Then I have a storage unit I built out of mahogany with double-deep individual bottle racking. I was just lucky to find a local lumberyard that had some mahogany planks they wanted to get rid of! But the natural humidity in my area on the East Coast is normal to high, so I don’t try to regulate it, or aim for anything extreme that might cause “ordinary” woods to rot out! You should be OK in your area as well I would think. And late summer temps in the high 60s is OK for anything other than storing Champagne for 20+ years! :slight_smile: As long as it is cooler most of the year. Or else too, you can add some standard A/C, or better, a “split system”, where the compressor is outside.

Also, look around and check your southern exposure, i.e. where you will get most direct sunlight. Shade trees, shrubs, and grass help keep the soil near the foundation cooler. Don’t put up racking on a wall that gets direct sunlight on the outside, as that wall will be the warmest! The north side is usually best. Dr. Gold has an excellent little book, “How and Why to Build a Wine Cellar”, or something like that. Don’t know if it is still in print, but a search on Google for Dr. Gold, or the title might bring up something.

As long as you are only interested in drinking the wines - which is to say, AS LONG AS YOU DON’T CARE ABOUT AUCTION RESALE VALUE - then flooding in Washington State [i.e. cold water flooding] won’t hurt the wines at all.

On the other hand, the slightest water damage to the labels [even if it’s only humidity damage] will ruin the auction resale value.

  1. Yes, pictures please!

  2. Sorry if I missed it, but do we know what constitutes the “floor” in this crawlspace? Is it a dirt floor or a concrete floor or a raised wooden floor?

  3. If the concrete walls have earth [as opposed to air/atmosphere] behind them, then I would strongly urge you to keep the walls open so as to act as a natural cooler in the summertime. Which is to say - if there is earth behind the concrete walls, then do NOT put any sort of insulation in front of the concrete walls - you’d be trapping the hot air in and keeping the earth [via the concrete] from exercising its natural cooling influence.

It really is amazing how cool a basement stays in the summertime if the floors and the walls are nestled directly in the earth [i.e. no raised floors and no walls exposed on their exterior sides].

the floor is wood… just wood planks… unstained (or none i can tell)?

Any recs on where to get racks? or just buy 2x4 and build it myself?

You save a LOT of money if you build them yourself. Attach to walls with something like this (they come in various sizes, from really small to really huge):


Use a masonry bit to drill into the cement and put in some plastic anchors and you’re good.

Space the shelves so that you can fit your bottles between them - average Bordeaux shape is 3" diameter and 13" long. Turley’s and some Rhones are like 3 1/2 inches diameter and mags even larger, so leave a few spots with at least 4" spacing and for the others you can get by with 3 1/2 between shelves.

You don’t really need 2x4s - that’s kind of overkill, and if they’re not dried properly, they may twist and turn.

Plywood is dimensionally stable and if you rip a few boards, you can make very servicable shelves. Use at least 3/4" and it will sustain the weight. If you rip a 48" piece of plywood just into just under 9 1/2", you’ll get five shelves per sheet. You’ll make the shelves just over 9 inches wide or so and you’re fine. The necks can stick out and mount the shelves slightly away from the wall - like an inch, so any moisture doesn’t wick out into the wood.

Good luck!

Put in a remote therm and temperature for the last 5 days:

Min: 55.1F. Max: 56.1F
Humidity: 62%
I think the temp is pretty ideal but is the humidity ok? too high?

Other data: Outside temp is around 40-50 throughout the day. Inside the house is heated to 68-70F

Humidity is fine. temp is fine. Your issue will be July and August when the temps are in the 80s. In your shoes I’d find some way to incorporate an inexpensive 5000 BTU AC unit (a window one). That will cool to the mid 60s without modification which is fine for the 2 months a year when we have really hot weather. Home Depot has units like this for $99 and it’s cheap insurance. I’d bet that for 8 to 9 months of the year your passive temps will be under 6 and for the shoulder months before and after ‘summer’ they’ll be in the low-mid60s.

Rick, where would i blow the hot air to for the AC unit? there isn’t an actual window? blow it to the neighbouring crawl space area?