Passive cellar temperature question - is 72 too high?

[Shar_N]

Makes perfect sense! Thanks! I may have to look into adding a portable AC unit then.

[MChang]

Do most ppl not have AC running through their basement? I just have an opening in a vent. The cellar tomm and we hold 55 without insulation.

[Shar_N]

I’ll check again but I think everything runs thru the attic.

[EdvardsA]

Having AC in the house greatly depends on US vs Europe, probably other regions as well. The latter barely uses any ACs especially if it’s an older house.

Then again, no idea what countries are represented here. Probably heavily leaning towards US majority.

[john_stimson]

Did anyone mention Brett concerns? I think allowing temps to reach the low 70’s is fine, except that in my mind, anything above 60 is a concern with regard to allowing the potential for brett blooms.

[Brian_Gilp]

My cellar is at 65 right now and will peak out around 70. I haven’t had any issues with Brett. I put the cellar in roughly 20 years ago and am fairly diverse in holdings. Either I don’t have wines at risk or these temps are not a concern.

[David_Bu3ker]

Well then don’t store Chateauneuf.

[john_stimson]

Hah! No risk of that, here, though.

[Shar_N]

Is this the type of insulation you’re referring to? What type of glue did you use to attach them? I’m thinking to build a cooler box with this and monitor the temps. If it works then I can use it to section off the entire NE corner.

[David_Patte]

Yep— Brett can slow down at lower temps, but to really avoid a bloom you need to be below 55F, and I recall hearing an interview that found certain Brett strains can thrive at much lower temps. Sigh. Same with oxidation— you need to be lower than 59F to start reducing oxidation potential (25% reduction for every 1F lower than 59F) according to Clark Smith for example. This is the main reason to shoot for 55F if possible. But keep in mind that cork quality and integrity have improved dramatically over the years (we get “guaranteed” low oxygen transfer rates from producers) and this is not as big a concern as it was 30 years ago.

At any rate, not sure there much difference between 60, 65, 70F (etc). That said, I haven’t looked at research for what might be considered “high” temp storage limits…

[John_Morris]

@Shar_N

July is the hottest month here but I’m not sure about the ground temps. I irrigate the lawn 3 days a week and daily in September, does that help with the ground temps?

Watering won’t help. Gold’s book on passive cellars has some surprising figures on ground temps. Even six feet down in New England, the soil temp can be above 60, as I recall – maybe even mid-60s.

There’s also a lag between outside temps and ground and cellar temps. My passive cellar is up to the low 60s now because we had some very hot weather in June. Some years, when the outside temps don’t reach the 90s until July, the cellar temp doesn’t max out until August.

[John_Morris]

@David_Patte

Yep— Brett can slow down at lower temps, but to really avoid a bloom you need to be below 55F, and I recall hearing an interview that found certain Brett strains can thrive at much lower temps. Sigh. Same with oxidation— you need to be lower than 59F to start reducing oxidation potential (25% reduction for every 1F lower than 59F) according to Clark Smith for example. This is the main reason to shoot for 55F if possible. But keep in mind that cork quality and integrity have improved dramatically over the years (we get “guaranteed” low oxygen transfer rates from producers) and this is not as big a concern as it was 30 years ago.

Thanks for the detail! I’d recalled reading that brett could really take off someplace in the high 60s, but I can’t recall the source.

Footnote: Greg Tatar has sometimes argued that there was no research supporting the 55F accepted wisdom. He suspected that that just reflected natural cellar temps in England.

[John_Morris]

OK. You two need to duke it out:

@David_Bu3ker

I have an “overflow” area in my basement where I keep the cellar defenders and stuff I want to drink relatively soon, and it touches 70 in the summer, but only for about 8 weeks or so. Most of the rest of the year slowly swings from 54-65. It’s under 60 2/3 of the year. Even stuff that has “accidentally” ended up in that area for 10 years has still been essentially unaffected. I’ve even done control samples with blinded tastings of identical wines both in the 53-55 degree wine cellar and the overflow space.

Alan Rath:
When I first started buying “nicer” wines (which at the time were still fairly ordinary california red wines), I built a small storage rack that I put in the closet where I access the crawl space under my house. I figured that was the coolest space I had. Any bottle in there for 2-3 years was definitely more developed than it would have been stored at 55-60. They were drinkable, but not as good as they should have been.

[David_Patte]

Oh totally, many historical practices worked well and we might see them as “accidental” but these were traditions handed down over generations of learning as you go. My grandparents in France had a deep cellar on the farm for many reasons— most important to them was that it functioned as they perfect root vegetable cellar. Wine was there too. Can you imagine back in the day, not an “inexpensive“ proposition— all hand labor … (the farm was 18th Century construction)

[VladB]

@David_Bu3ker

I have an “overflow” area in my basement where I keep the cellar defenders and stuff I want to drink relatively soon, and it touches 70 in the summer, but only for about 8 weeks or so. Most of the rest of the year slowly swings from 54-65. It’s under 60 2/3 of the year.

This is very close to the cellars of Chateau Margaux if I remember correctly.

[Phil_T_r_o_t_t_e_r]

@VladB

This is very close to the cellars of Chateau Margaux if I remember correctly.

I’m thinking you’re talking about temperature here and not the:

@David_Bu3ker

I have an “overflow” area in my basement

[Jay_B]

Even with AC keeping a basement at 55 seems like a stretch for most houses if outside temps are reaching 90+ in the summer.

Is it the AC keeping yours at that temp or maybe you have a really deep basement? If it’s the AC does that mean you have it in a separate zone with temp control set to 55 such that it kicks on at 56?

[Jay_B]

This thread puts me at ease about my own basement closet cellar.

My space’s peak temps (in PA) just barely hit 69F end of last summer/early fall and I don’t think I’ve dropped below 64F in the year since I’ve monitored. It’s a small closet: tile floors, no insulation, flimsy door that keeps sun out. Have thought about installing a temp-triggered circulation fan in the door itself to push/pull air…

For now this works for my purpose since most wine goes to offsite, “long-term” home storage and/or nicest bottles go in a small wine fridge, and everything else (maybe a couple hundred bottles) goes into the closet. “Closet wine” rotates pretty quickly anyway.

[MChang]

@Jay_B

Even with AC keeping a basement at 55 seems like a stretch for most houses if outside temps are reaching 90+ in the summer.

Is it the AC keeping yours at that temp or maybe you have a really deep basement? If it’s the AC does that mean you have it in a separate zone with temp control set to 55 such that it kicks on at 56?

It is keeping it at 90. We don’t have a super deep basement. The soil is clay, though, which is naturally insulative.

I manually control the AC with a nest thermostat to maintain appropriate cellar temps.

[lleichtman]

We use our crawl space for wine storage but it gets too hot in summer and too cold in winter so we insulated the area where the wine is stored and keep a constant 62º