Wine cellar questions

[ChuckD]

Having been bitten by the wine making bug, I have converted my root cellar into a "wine cave". I ripped out some old decaying shelving (non treated lumber) and outfitted it with some new shelving including a 10-foot long shelf on the long wall for secondaries and three-high shelves in the back for wine bottles. I planned on using some plastic crates I found at Menards for bottle dividers... they hold 16 bottles each. I already have plans for a matching three-high shelving along the right side wall. I have been reading everything I can find online about wine cellars but most of the content references those fancy multi-zillion dollar climate controlled wine rooms. As you can see, mine is intended to be passive only... and not so pretty.

A few questions:
1. My cellar has a gravel floor with drainage underneath... I have never had standing water in the cellar. Would concrete be better?
2. I have not monitored the temperature closely but It stays below 65 degrees in the summer and just under 40 degrees in the winter. I know this is outside the published ideal range for wine storage but it's what I have. Right now the entrance faces west and the block is directly behind the stone retaining wall which is about three feet thick. I think I am losing/gaining a lot of heat through this wall and the poorly sealed door so the plan is to add 2" of insulation (r10) to the inside of that wall, increase the door insulation to 4", and weatherstrip the door. Hopefully that will decrease the annual temperature swing. being underground the temperature changes seasonally but there are no short-term fluctuations. Is this acceptable for bulk aging and bottle storage?
3. There is a 4" vent pipe through the roof at the rear of the cellar. Is this good or should I cap it?

Any other thoughts would be appreciated.

Also, I know it seems like a lot of work for eight bottles of wine, but I only made 10 gallons last year and a wedding and family reunion pretty much drank through that. I have 22 gallons brewing right now and plans for more in the spring, so come next summer I should start filling it up. If I don't give my wife the combination to the door, I might even start building an inventory .

Chuck

 

[Rice_Guy]

1) concrete is nice mainly since you don’t have to worry about wildlife, But not essential! gravel will pack and make a nice work surface. you have washed stone? ,, which never packs, I would create a flat work surface by laying plastic decking over traffic areas. decking could be vacuumed if you ever break a carboy. ,,,, Remember in the old days everyone had a soil/ gravel surface, also food plant rules if it touches the floor we scrap it.
2) the temperatures aren’t bad! Daily cycling will draw microgram levels of oxygen through corks so daily cycles are bad. I like insulation, remember good gaskets on the door. ,,,, this is better than what many of us have.
3) the vent will be extremely useful, example if you want to run power to the cellar or put solar on the top with battery lighting. Yes I could see putting a removable closed cell foam plug in it. This also leads to humidity control choices.
4) humidity, do you have a way to monitor it? At 80% RH you will see mold on everything, including treated wood. At 50% you should be stable. This leads back to a floor, modern concrete will put a plastic moisture barrier in, if you need humidity control consider using a high density expanded polystyrene panel instead of eight mil poly.

. . . wish I had a space like that , ,

 

[winemaker81]

If you wire for lights, you can add a small heater for the coldest part of the winter.

 

[salcoco]

try to keep the temp variance to less than 10 degrees.

 

[balatonwine]

Remember in the old days everyone had a soil/ gravel surface

Our wine cellar floor when we bought the property was simply dirt. Was dirt for the 100++ (do not know exactly) or so years the cellar existed before we bought it.

Our "upgrade" was digging down a bit, then adding compressed gravel then bricks**. The bricks simply helped to keep the floor level without issues if things "spilled" and needed a bit of mopping up (to prevent the floor from getting "fuzzy"....). Never even considered concrete.

** The bricks were also maybe 100 years old, from a nearby demolition we got rather cheaply.

 

[ChuckD]

Thanks for all your input.

The floor is washed stone, so it won't pack down. I never even thought of brick... that would look really nice and maintain drainage. I'll keep my eyes open for some used ones.

As for the temperature swings, I hope the added insulation will tighten that up a bit but I don't know if I can keep it to 10 degrees annually. I thought stability was more important than the upper and lower limit, no? I think I'll start looking for a reasonably priced recording thermometer and humidistat. Any thoughts?

When I built the cellar, I put a 3/4" pvc pipe through the roof so I could run electricity. I think I'll push a rod up through that so I can feed some power in there. It's too late for trenching now but I could run an extension cord from the house for this winter.

 

[ibglowin]

In a perfect cellar you try and minimize daily temp swings as well as annual temp variations. So IMHO anything you can do to further insulate the cellar will minimize the daily temp swings. Your Summer high temps are not a huge concern but anything you can do to keep it a little cooler will help out (again insulation should help here). Your Winter temps are however much cooler than preferred so anything you can do to bring those temps up closer to 55 will really help IMHO. Your wine is basically being cold stabilized for months each winter so you may see larger amounts of wine diamonds dropping out at those temps. Again insulation will help here and perhaps closing off the roof vent during the winter may help if your losing heat there. Lastly placing some sort of heater in the cellar during the coldest months of the winter should be a possibility. Perhaps one of those oil filled electric heaters would be enough to bring the temps up into the lower 50's.

If you have Wifi at the house one of these is great for keeping track of both temp and humidity with data logging (free).

https://www.amazon.com/gp/product/B0872ZWV8X/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
If no wifi then at least pick up a cheap temp/humidity gauge that at least you can look at the temps/humidity when you enter the cellar each time.

 

[balatonwine]

I never even thought of brick... that would look really nice and maintain drainage.

Yes, the brick, looks very good.

For reference, photos (10 years ago), below. After the walls were renovated, and fine gravel being laid down, then after the bricks are laid (and we started piling in some of our junk.... sorry for the mess.....)

 

[ChuckD]

In a perfect cellar you try and minimize daily temp swings as well as annual temp variations. So IMHO anything you can do to further insulate the cellar will minimize the daily temp swings. Your Summer high temps are not a huge concern but anything you can do to keep it a little cooler will help out (again insulation should help here). Your Winter temps are however much cooler than preferred so anything you can do to bring those temps up closer to 55 will really help IMHO. Your wine is basically being cold stabilized for months each winter so you may see larger amounts of wine diamonds dropping out at those temps.

Thanks. I just ordered a non-smart thermometer/hygrometer with 24hr max/min for the cellar. being underground I don't think daily temperature swings are going to be the issue, just the seasonal swing. I know colder temps speed settling of lees, and I have come across cold stabilization in my readings... is it a good thing to do? and what are the ice diamonds you speak of? I do have an oil filled heater that I use in my basement bathroom/fermenting room. If needed I can put that in the cellar during the coldest months.

 

[sour_grapes]

Wine diamonds (not "ice diamonds") are preciptated potassium bitartrate (aka, cream of tartar).

 

[winemaker81]

Cold stabilization is cooling the wine to below 40 F and keeping it there for a week or 2. Closer to 32 F is better, but any temperature in the range works. Some folks will go below freezing, but I recommend against it. Freezing wine damages it, and the freezing point of wine is not a constant value -- it varies with ABV, sugar, and other constituents.

The cool temperature lowers the saturation threshold for tartaric acid, and excess drops out of suspension as crystals. This reduces the acidity of the wine somewhat and has the side benefit of clearing the wine, as other solids will drop with the tartrates.

Rack the wine before it warms up.

If the wine is not high in acid, I don't see a real value in cold stabilization. When I lived in Upstate NY, I did it for my Finger Lakes whites as they were all high in acid. Putting the carboys on my porch for 2 weeks reduced the acid and they came out crystal clear.

My cellar is 58 F in the winter and I've noticed some wines have dropped crystals at that temperature. Some folks bulk age at a lower temperature, as some crystals may drop -- this prevents crystals in the bottle if someone leaves one in the fridge for a week or 3.

 

[jak]

Keep in mind that anything you do to insulate decreases air flow which will increase humidity. I would not use an kind of oil heater as it will make some fumes (even if it says ventless heater). But if you use a burning heater, I would also add a carbon monoxide detector in there. Elec heater would be safer. If humidity is too high, you could put down plastic sheathing under bricks or planks or even sheets of plywood. Yes, wood and plastic sheathing on the floor would fail eventually, but it will last for years.

 

[ChuckD]

I'm OK with the washed stone for now... I just like the look of brick so I will do that if I can find some freebies. The oil filled heater I have is an electric heater with oil in it to absorb and radiate the heat. They do a good job of maintaining a set temperature with minimal fluctuation. Copy that on the humidity with ventless heaters... I use a propane construction heater and wood stove in my shop, and you can't burn the propane too long or you get lots of condensation on cast iron tools which leads to rust. My new digital thermometer/hygrometer for the cellar should be here on Monday so I can monitor humidity levels.

 

[ChuckD]

So, the temperature in the cellar had been sitting tight at 44 degrees so I added 2" of high-density foam-board to the "outside" wall, plugged the vent pipe, and weather stripped the door. After a few days the temperature climbed about two degrees. On the outside of the roof, I have two inches of foam-board and about two feet of fill so I'm probably losing a lot of heat through the ceiling as well. I have one of those infra-red thermometers, so I checked, and the roof was 42 degrees while the lower walls and floor were at 48. Yesterday I put my oil-filled heater in the cellar and set the temp to 48 degrees and that's where it was today. I plan on increasing the temperature a few degrees a day until I hit 55 or so then leaving it there for the winter.



My thermometer/hygrometer won't be here until tomorrow, so I don't have any humidity readings, but it feels really high right now... like nearing 100%... my breath was condensing on the ceiling and my note pad was damp after a few hours. What are my options for humidity control? The cellar is 6.5 feet x 10 feet with a 6.5 foot ceiling height. Is a room sized dehumidifier too large? should I open the vent and put in a fan to circulate the air a little? should I seal the block walls? Any help would be appreciated.

 

[hounddawg]

a dehumidifier might help you, they tend to be handy in underground homes,
Dawg

 

[hounddawg]

i have been contemplating on some 8 foot tall by 10 foot long galvanized culvert, placed where the top is at a elevation of 4 feet below the surface,
with access from a closet down to a wine bottle cellar,
Dawg

 

[Rice_Guy]

*the first step in humidity control is to have a vapor barrier on all surfaces, especially the floor.
* you have a heater running now, so I doubt that you are close to 100%, it is called relative humidity not absolute humidity. The moisture holding capacity of air increases as the temperature rises therefore a constant N grams of water could be 100% at 42F (ceiling) but a significantly lower at 55F.
* barrels are best with higher humidity since it reduces the angels share
* fans/ air movement reduces the risk of mold (localized high humidity)
* a small motor operated dehumidifier might be overkill/ act as a heat source, the one I run in the basement has a digital humidity readout and will cycle on/ off instead of just running
* there is a chemical/ no electricity moisture pickup system which is advertised for closets, might be enough especially on a tight box
* venting is trial and error, you need readings to get an idea how much moisture wicks in, if you don’t have iridescent salt build up on the walls wicking moisture shouldn’t be too bad
* your photo looks good, expanded polystyrene tolerates moisture but isocyanurate board doesn’t (it is a nitrogen polymer).

My thermometer/hygrometer won't be here until tomorrow, so I don't have any humidity readings, but it feels really high right now... like nearing 100%... my breath was condensing on the ceiling and my note pad was damp after a few hours. What are my options for humidity control? The cellar is 6.5 feet x 10 feet with a 6.5 foot ceiling height. Is a room sized dehumidifier too large? should I open the vent and put in a fan to circulate the air a little? should I seal the block walls? Any help would be appreciated.

 

[montanarick]

*the first step in humidity control is to have a vapor barrier on all surfaces, especially the floor.
* you have a heater running now, so I doubt that you are close to 100%, it is called relative humidity not absolute humidity. The moisture holding capacity of air increases as the temperature rises therefore a constant N grams of water could be 100% at 42F (ceiling) but a significantly lower at 55F.
* barrels are best with higher humidity since it reduces the angels share
* fans/ air movement reduces the risk of mold (localized high humidity)
* a small motor operated dehumidifier might be overkill/ act as a heat source, the one I run in the basement has a digital humidity readout and will cycle on/ off instead of just running
* there is a chemical/ no electricity moisture pickup system which is advertised for closets, might be enough especially on a tight box
* venting is trial and error, you need readings to get an idea how much moisture wicks in, if you don’t have iridescent salt build up on the walls wicking moisture shouldn’t be too bad
* your photo looks good, expanded polystyrene tolerates moisture but isocyanurate board doesn’t (it is a nitrogen polymer).

You are always a wealth of information

 

[ChuckD]

I got my temp/humidity gauge today and put it in the cellar. After 6 hours of acclimation the temperature is 46 degrees with a relative humidity of 83%. I'm still increasing the temperature slowly with the heater (shooting for two degrees per day or less) so we will see where the humidity is when I hit 55 degrees.

For now, I'm just going to add a small fan to circulate the air. Once I get the temperature up, I'll try playing with opening the vent a little to let some of the moist air out. I could add vapor barrier to the floor but I sure as hell won't be digging up the cellar to add vapor barrier to the walls. A dehumidifier would work in the winter because I could actually use the heat they generate. In the summer it might create too much heat. Either way, I would rather not spend the $200.

 

[Rice_Guy]

In home construction the vapor barrier is applied to the warm side of the wall, this is to prevent humidity in the living area from hitting cold fiberglass > creating ice > losing essentially all insulation value. For home use I think the paint companies have come up with basement wall barriers as Ugly Paint. @mainshipfred you are in the business, any favorite wall skin? Menards also has a builder counter where contractors can leave their business card, it might be worth while talking to some local folks who do basements, ,,,, this is not a new problem.
You are thinking about slowly getting to a target of 55F. My gut feel is that a soil moisture balance creating today’s humidity will take longer than reaching a temperature balance, if you have a controller like an ink bird ($19) I would set it where you want the temp and let the controller do the monitoring so you get to a soil moisture balance faster. (Ink bird also has cooling contacts for summer). You are in a part of the country with snow/ freezing soil, you will actually reach a winter equilibrium. When the soil thaws expect that you have a new seasonal balance and that summer is the only time where mold is an issue. ,,,, mold spores in the environment is low in heating season.
Using 1970s technology one of the labs at U of I ran summers with AC cooling below target and then heating the air back up to proper working temp/ relative humidity. Granger and HVAC companies have controls to automate this. ,,,, There are neat solutions like condensate pumps and condensers but if you can use a chemical absorbent it sure is a lot less fuss.

I got my temp/humidity gauge today and put it in the cellar. After 6 hours of acclimation the temperature is 46 degrees with a relative humidity of 83%. I'm still increasing the temperature slowly with the heater (shooting for two degrees per day or less) so we will see where the humidity is when I hit 55 degrees.

For now, I'm just going to add a small fan to circulate the air. Once I get the temperature up, I'll try playing with opening the vent a little to let some of the moist air out. I could add vapor barrier to the floor but I sure as hell won't be digging up the cellar to add vapor barrier to the walls. A dehumidifier would work in the winter because I could actually use the heat they generate. In the summer it might create too much heat. Either way, I would rather not spend the $200.