Design a Wine Cellar

Although most bottles of wine you purchase in the store are sold ready-to-drink, wines made with certain grapes can and will improve with age. That’s not the case for home winemakers, whose freshly bottled wines often require a minimum of a few months of bottle aging for white wines, and a year or more for red wines. Many red wines benefit from much more time to age in the bottle. That Nebbiolo you made will taste quite different in 10 years’ time. Even your Cabernet Sauvignon and other red wines will improve after a couple of years in proper storage. For that, you are likely to need a designated wine cellar.

When we talk about proper storage, winemakers need proper wine cellars to safely age their bottles or else they run the risks of ruining their wines during the waiting period. Extreme temperature fluctuations, constant vibrations, high ultraviolet (UV) light, and excess humidity can all negatively affect wine. The best wine cellars offer home winemakers, wine collectors, or anyone else stockpiling wine a stable, secure, chilly space that exists in complete darkness 99.9% of the time. 

In this article, I will discuss many of the construction options that a homeowner might consider when designing a wine cellar.  I’ll channel the advice of a friend — Keith Travers, a building contractor in Oakville, Ontario, who got schooled on the subject by a local wine cellar manufacturing business when he sought their help with a recent basement renovation. Keith wanted to buy pre-made shelving to fit a 100-square-foot (9.2-square-meter) spot where the homeowner had written “cold room” on the plans, but later confessed to Keith how he hoped to store his wine in the space. Keith soon discovered that a wine cellar is more complicated than a cold room and it requires a lot more than wooden wine racks.

Wine Cellars vs. Cold Rooms

Because the way wine is stored and handled affects how it tastes when served, wine cellars matter, and they’re much more complex than cold rooms. Wine stored in garages and under the front porch of houses is subject to excessive temperature fluctuations as the weather changes day-to-day and from season-to-season. There is nowhere outside on planet earth that doesn’t experience daily temperature changes as the sun rises and falls in the sky overhead. To keep a constant temperature in the wine cellar, the room needs proper insulation, as opposed to cold rooms where the walls are left bare by design. That’s not to say cold rooms can’t be turned into great wine cellars — it will just require insulation and some work.

In addition to applying 2-inch-thick (5-cm) spray foam insulation, which forms a high-quality vapor barrier, Keith ordered a wine cellar cooling unit and designed a ducted cooling system. Wines are best stored from 40–65 °F (4– 18 °C). The optimal storage temperature depends on the wine’s age and how long it will be stored. If the bottle will be opened within a year or two, a warmer temperature of 60–65 °F (15–18 °C) will speed the development of the wine’s bouquet. The best stewards keep the temperature perfectly tailored to the wine being stored.

Maintaining the optimal temperature and avoiding temperature swings in the cellar are the two most critical exercises for proper wine storage. To achieve this, cellar owners must minimize the potential coolness loss in windows and poorly insulated doors and ceilings. More on
that later.

Sizing Your Wine Cellar

Keith bought generic wooden wine racks made from 3⁄4-inch (1.9-cm) thick wood. A single 48-inch x 48-inch (122-cm x 122-cm) square section of this type of thin racking holds 96 bottles (750 mL). A rough extrapolation and close approximation of the room left Keith believing he could get about 870 bottles racked. There are thicker wooden racks available, which hold less bottles for the amount of space they take up. For example, if the racks with the same dimensions and array for storing wine were fashioned from 11⁄4-inch (3.2-cm) thick wood, space for a dozen bottles would be lost.

If you are working with a small space and you believe more room for a greater capacity of wine may be required, metal pins grouped tight together could be used in place of a wine rack to allow for the most possible bottles on the wall (if you haven’t seen this option before, images can easily be found online if you search for “vino pins” or “vino rails”). The small cellar could have held over 1,200 bottles in that configuration. But, as I mentioned, the building contractor went with the thin wooden racks (which were the cheapest option and look great).

When designing your own cellar at home, consider the type of wine racks you want — both aesthetically and with consideration of how many bottles you expect to store in your cellar. Costs may also vary greatly, depending on the style, material, and finish. Or, if you are handy, there is also the option of making your own wine racks. WineMaker has run a number of stories over the years with plans for various style wine racks. Links to a few can be found at the end of this story.

 From there, you can gauge how much space you will need in your cellar. Also, think to the future; is there a chance you start making more wine in the future, or the number of bottles being cellared continues to grow over the years? Plan ahead — even if you don’t install more wine racks than you plan to fill immediately, you will want to have space to grow when the time comes if there is any chance of it.

Plan Out Proper Ventilation Before Wine Cellar Construction

Proper ventilation is critical for long-term wine storage as it must allow for sufficient air-flow to help eliminate odor build-up, or mold, which can harm wine bottle corks and labels, and of course moldy cellars ruin houses. 

During the wine cellar design phase it’s important to include an adequate method of ventilation and airflow. In this case, Keith knew the wine cellar cooling unit would be located beside the water tank and furnace, and the ventilation could be ducted into the space from this central area. Normally the room beside the wine cellar accommodates the cooling unit, but this newer house had central air and an existing duct work system. Keith selected the smallest volume Whisperkool unit available online, and he installed the smallest ducting system he’s ever built into the tiny insulated room; this refrigerated room was 100-square-feet (9.3-square-meters) in surface area, with a 9-foot-high (2.7-meter-high) ceiling to make a combined 900 cubic feet (25.5 cubic meters) of refrigerated space. Make sure to factor in the size of the room when making the decision on a cooling unit to ensure the model you choose will do the work.

Lighting Your Wine Cellar

Fortunately for Keith, the area of the basement the homeowner selected had no windows that needed to be worried about in terms of heat gain or light penetration. He would have installed shutters if this were the case. Daylight is a nuisance for cellar managers as ultraviolet light can cause oxidization of tannins in wine, causing an unpleasant taste and aroma. Sparkling wines are even more sensitive to light (all spectrums) and should be given extra care when stored in wine cellars with lots of foot traffic and fingers on the light switches. Simply being packaged in dark glass bottles is not enough protection; delicate, light-bodied white wines still need to be stored in very dark places. Light switch timers are recommended in places where people will forget to switch off the lights as they leave the cellar.

For the wine cellar’s overhead lighting needs, Keith selected LED pot lights with very well-insulated pots. Light-emitting diodes come in a variety of shapes and configurations and can be made to look incredible in any space. While tungsten filament pot lights on a dimmer switch may seem like an easily deployed and easily controlled solution, the pots are seldom insulated well enough to avoid heat loss through the top of the can. Above all else you should never have fluorescent lights in your wine cellar. Fluorescent lighting emits significant amounts of ultraviolet light, which negatively impacts wines on a photochemical level. UV light can mature wines before their time. Sunlight, fluorescent lights, and even some tungsten filament incandescent lighting can adversely react with phenolic compounds in wine and create wine faults as well. Again, limiting light exposure is key to wine storage.

Selecting the right wine rack design

I know, I’ve already mentioned the option of metal wine pins to optimize storage space for wine, and those will work well in some homes, but for many people wooden wine racks are going to be much friendlier to their wine. For the same reasons that automobiles travel on rubber tires, wine cellars depend on wooden wine racks to absorb the smallest vibrations that will ruin the wine’s flavor over time. Does a garbage truck’s trash compactor shake your windows once a week, or the nearby freight trains make the dishes rattle? If so, you cannot store wine on your home property unless you have wooden wine racks on rubber mats. If your racks are made from any other material, the neighborhood’s vibrations, whether once a day or twice a week, will add up to hundreds of shakes over the years and may lead to premature aging and other undesirable changes in your wine. If your cellar is in a basement where vibrations would be few and far between, then that may mean you can get away with a different option.

As most wine lovers already know, wine bottles closed with corks are always stored on their sides so the corks remain wet; in this horizontal state the transmission of air through the cork into the wine is minimized. When bottles are stored upright, the cork eventually dries out and oxygen in the air seeps through, causing chemical changes in the wine (not good chemical changes!). Additionally, when wine bottles are stored upright in adverse conditions some corks may work loose due to pressure changes and this can cause leakage or oxidation. For this reason, proper wine cellars have racking solutions that lay bottles horizontal. 

Wall anchored wooden racks are typically the best choice for long-term storage as wood dampens small vibrations, and wall anchoring helps to eliminate any sway in the racks (and its especially important if you live in an area where earthquakes are a possibility). Woods like beech, redwood, maple, and mahogany are often the recommended choices for wine cellar racks because these species respond well to the cool, moist environment of cellars, and these woods do not impart any negative odors that may be absorbed through the corks and into the bottles as the wines age.

Importance of the Wine Cellar Door

The door to the wine cellar is often one of the most overlooked aspects when designing your space. However, it is important.

The entrance to the cellar should have a lock. Wine cellar doors should be locked for security reasons or to keep minors out, but also to make people aware the door always needs to be kept shut. The room is a temple and needs to be left dark and undisturbed. Even if you aren’t worried about your wine disappearing, unlocked doors often have a habit of being left open. 

For temperature reasons, the space will need an exterior-style or insulated door. The task is to pick a thermal barrier that is also aesthetically pleasing and seems like it is part of the interior decor. I’d suggest avoiding wine cellar doors with glass panes due to the light leak. It can be challenging to find the perfect door that looks right and is also functionally and technically sound. Improper doors leak cool air, which is bad for the wines inside the cellar, not to mention your home heating bill. Because a stable and pervasive chill inside the space is the primary objective, the door needs weather stripping and should close with a solid “thump” that indicates a firm air-tight seal has been made between the two spaces. 

Other Considerations for Basement Wine Cellars

Keith purchased two-inch-thick rubber mat tiles for the floor (to reduce vibrations on the wine racks) that he could cut and shape to make uniform coverage throughout the room. The designated space was rather small, and this meant that it would be easy to refrigerate, but what about the humidity? The whole neighborhood was prone to flooding and even with the best waterproofing the walls sometimes wept with excess moisture. Keith knew that besides the vapor barrier insulation, the room may also require dehumidification through proper ventilation
and monitoring. 

Relative Humidity (RH) is the percentage of vapor saturation in the air at a given temperature. Storage humidity levels should ideally stay between 50–70%. When humidity is too high, mold can form on your corks and on your labels, which are then considered ruined (excessive humidity does not affect the wine inside the bottle, however, as long as the cork is intact). If the humidity is too low, even bottles stored on their sides may experience drying of corks. Corks can grow mold at the end, which will not harm the wine providing the seal is not broken, but something that you likely want to avoid. Adding a humidifier to your wine cellar is the easiest way to ensure the RH in your storage room is optimal and will give you peace of mind. Just remember to empty it if your system is not piped into a drainage system.

In summary, remember the wine cellar manager is a guardian of flavor. He or she cannot control nature, or the geography or climate in which they live. Nor do they have any control over the amount of rain that falls, or sun that shines. All they can really manage is the quality of their wine cellar, and especially its construction, and its day-to-day operation as they struggle to stay cool in all seasons. With adequate planning prior to construction, the factors that are beyond your control can be neutralized, and your wine should be good for the years to come.