Wine cellar temperature and humidity: what to design for

A cellar built for long-term storage should hold a steady 12–14 °C (54–57 °F) and roughly 60–70% relative humidity, in the dark and with little vibration. Purdue Extension gives 10–16 °C (50–60 °F) as the traditional cellar range, with about 13 °C (55 °F) as the reference. For any wine cellar temperature and humidity brief, stability matters more than the exact number.

A glass-fronted cellar can show exactly the set temperature on a winter morning and still have fogged glass at the lower corners. The glass is colder than the air in the hall beside it, moisture condenses on it, and the unit is working against a wall that was never insulated for the duty. The number on the display was right; the design behind it was not.

What temperature should a wine cellar be?

For long-term storage, around 12–14 °C (54–57 °F), held constant. The classic reference point is 13 °C (55 °F).

Purdue Extension’s Wine Storage Guidelines (C. Butzke) describe 10–16 °C (50–60 °F) as the traditional cellar range. Purdue notes that any temperature above 16 °C (61 °F) accelerates maturation and can shorten a wine’s life, especially whites; above 24 °C (75 °F) most wines age greatly and untypically. The Australian Wine Research Institute reaches a similar conclusion in its technical note Effects of heat and light on wine during storage: long periods above 25 °C (77 °F) harm quality.

Storage temperature is not serving temperature. Mixing the two is a common reason published figures seem to contradict each other. A cellar is set for keeping, and bottles are brought to the glass separately.

Why does stability matter more than the exact number?

Repeated warming and cooling is harder on a bottle than a steady figure that sits a degree or two away from the ideal. Purdue notes that ageing reactions speed up exponentially as temperature rises, so a cellar held a few degrees warmer matures wine faster. A bottle that rises and falls several degrees every day is being stressed continuously.

A slow seasonal drift of a degree or two is how traditional underground cellars behave, and it is gentle. What we design out is the quick swing: a cooling unit that cycles hard, a sunlit wall, a glass door, a draught from a badly sealed frame. This is why the envelope of the cellar matters as much as the unit that cools it, which we return to below.

What humidity should a wine cellar have?

Roughly 60–70% relative humidity is the working target, and many sources accept 50–80%. The reasons run in both directions: a 2023 PNAS Nexus paper notes that cork needs relative humidity above about 50% to stay elastic, while above 80% the risk of mould on the cork surface rises.

• Below about 50%: corks can dry and shrink, which lets air reach the wine.
• Above about 80%: mould appears on corks, timber and cartons, and paper labels deteriorate.
• In between: corks stay supple and surfaces stay clean, which is what you want for bottles kept for years.

Screw-cap bottles are not affected by humidity at the closure, but the labels, the timber racking and any cartons still are. High humidity is usually the harder problem in hot, humid regions, where outside air carries moisture into every gap. Low humidity is the common problem in air-conditioned or heated apartments. Both are solved first by the building, then by the cooling and humidity control.

How do light and vibration affect stored wine?

Light, especially at the blue end of the spectrum, can spoil wine, and vibration should be kept low as a precaution. The AWRI note describes light in roughly the 370–440 nm band acting through riboflavin to produce the fault known as light-strike, and shows that it develops much faster in clear glass bottles than in dark ones.

In practice this means three decisions. Keep stored bottles out of direct sunlight. Use UV-protective glass wherever glass is part of the cellar. Choose LED lighting, which gives off little heat and very little UV. Vibration is often said to disturb sediment in mature wines; the AWRI notes it could find no literature on harm from refrigerator compressor vibration, so keeping vibration low is a precaution rather than a proven rule. It is handled by placing the compressor away from the racks, mounting units on isolators and keeping the cellar away from machinery and heavy traffic. Bottles lie horizontally, or with the neck angled slightly, so that the cork stays in contact with the wine.

Can red and white wine share one cellar?

Yes. Storage conditions are the same for both, and only the serving temperature differs. A cellar held at 12–14 °C suits red, white and sparkling alike for keeping; the style then decides how long a bottle waits before it is poured. Restaurants that pour by the glass can separate display from storage; see restaurant wine display and hotel cellars.

Style	Serve at
Sparkling	6–8 °C (43–46 °F)
White	8–12 °C (46–54 °F)
Red	15–18 °C (59–64 °F)

Where a cellar includes a serving area, a separate zone or a small service cabinet can hold bottles at serving temperature, so the main cellar stays untouched. A made-to-measure wine cabinet can take that role.

How does the building, not just the cooling unit, hold the climate?

The building holds the climate, and the unit only replaces what leaks in. If the envelope is poor, even a large unit cannot create stability. If it is good, a modest one can.

That is why we start every cellar with a heat-gain calculation. The inputs include:

• the volume of the space and its position in the building;
• the temperature of the spaces next to it and the outside conditions;
• glass area, glazing type and exposure to the sun;
• lighting and anything else that gives off heat;
• how often the door opens and how many people use the space.

Insulation thickness follows the calculation and is applied to the floor, the ceiling and all walls, without thermal bridges. A vapour retarder sits on the warm side of the insulation, continuous across every junction, so humid air cannot reach a cold surface inside the construction. The door is an exterior-grade insulated unit with seals. Our planning guide covers the order of these steps.

In hot climates such as the Gulf, high ambient temperatures and large areas of glass make a proper heat-load calculation essential. It is the first step, not a refinement. The unit that follows is described in wine cellar cooling systems, and the particular case of glass is covered in our glass wine cellar guide.

How should you monitor temperature and humidity?

Read a trend, not a single value. A thermo-hygrometer that logs minimum and maximum readings tells you more than one glance at a display, because it shows whether the swing between day and night is small or large. Check it regularly and compare it with a second instrument from time to time, since low-cost sensors drift.

If the cellar is in a second home, on a yacht or anywhere you are often away, add alerts that reach your phone and a way to be told if power fails. We cover this layer in smart wine cellars.

How does Ardinart design for these conditions?

ARDINART Wine Cellars designs, builds and installs made-to-measure wine cellars, cabinets and storage at its own facility in İkitelli OSB, Istanbul. We treat the targets above as design inputs. Every cellar begins with the heat-gain calculation, then insulation, vapour control and the choice of cooling unit; rack and bottle layout, lighting and any tasting area follow. Cabinets are built to balance humidity inside, to protect bottles from UV through the choice of glass or door, and to protect them from vibration. The same team draws, builds and installs, so the person who calculated the heat load also sees how the door closes.

You can see how this plays out across cellars of different kinds in our wine cellar range and in the design and installation process.

Frequently asked questions

Is 18 °C too warm for storing wine?

For long-term keeping, yes. Wine stored at 18 °C (64 °F) matures faster than at 12–14 °C (54–57 °F), and the difference compounds over years. A stable 18 °C is acceptable for a limited time: Purdue’s shipping and storage table treats short exposure below 24 °C as tolerable for weeks, not years; for long-term storage stay within 10–16 °C. The risk is the combination of warmth and fluctuation.

Do screw-cap bottles need humidity?

The closure itself does not depend on humidity, because screw caps do not dry out the way cork can. The environment still matters for labels, timber racking and cartons, which grow mould or deteriorate when the air is too damp. If a cellar holds mixed closures, design it for the corks.

What happens if humidity drops below 50%?

Corks can dry and shrink, which can let air move into the bottle over time, and timber racking can shrink at its joints. A short dry spell does little harm. Persistent low humidity, such as in a heated or air-conditioned apartment, calls for a cellar built to hold moisture in.

Should I store wine in a kitchen fridge?

Only for a few days, before serving. A kitchen fridge is colder than any storage target, dries the air, vibrates with every compressor cycle and shares space with food odours. It is a short-term chiller, not a place to keep wine. If you are weighing a cabinet against a cellar, read wine cabinet or wine cellar?.

Where should the temperature sensor go?

At bottle height, in the middle of the racking, away from the cooling unit’s air outlet, the door, a glass wall and the light fittings. If you can place two, put the second at the far end of the cellar from the unit. The difference between them shows how evenly the cellar is cooled.

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The right numbers only help if the space can hold them. If you are planning a cellar or checking an existing one, we will go through the heat load, the envelope and the cooling with you. Book a discovery call.