Tips on Constructing Wine Cellars
Some things that should be considered when constructing a wine cellar are:

• Location of the Wine Cellar
  The location of the wine cellar is very important. When underground, it is best that it’s a room that is facing to the north. This is necessary as this wall receives the minimum amount of solar radiation during the day thus causing less retention of heat. The northern part of the perimeter of this room must not be adjacent to a road nor railway and made of stone or brick. The wine cellar must not be subject to unnecessary movement or vibrations. Vibrations can disturb and damage wine.
  
  

• Temperature of the Wine Cellar
  The wine industry has long considered that a constant temperature between 55 °F and 60 °F (13.0 °C and 15.5 °C) is optimum for the storage and aging of wine, provided any variations are very gradual. Temperature centered around 57 degrees Fahrenheit or 14 degrees Celsius, much like the cool caves used to store wine in France, is ideal for both short-term storage and long-term aging for all types of wines. This is done by keeping the wine underground and minimizing exposure to solar radiation. Note that wine generally matures differently and more slowly at the lower temperatures than it does at the higher temperatures.
  
  Residential wine cellars can be either active or passive. Active wine cellars are highly insulated and utilize air conditioning units to maintain the desired temperature precisely. Passive wine cellars take advantage of naturally cool and damp areas (such as basements with uninsulated outside walls in cool/temperate climates) when minor seasonal and diurnal temperature variations can be tolerated. Passive wine cellars may be less predictable, but cost nothing to operate and aren't affected by power outages.
  
  

• Humidity and Ventilation of the Wine Cellar
  Humidity must be controlled in order to keep the cork moist and functioning. A functioning cork maintains the integrity of the wine. The humidity should be between 70-75%. This level of humidity would cause mold to form in a normal house.
  
  
• Odors in the Wine Cellar
  Your storage space should be free of any extraneous odors as they can enter through the cork and contaminate the wine. It is recommended that wood racking be left untreated. If you do finish your wood racking allow ample time for all orders associated with the finishing to subside before using the rack to store your wine. Proper ventilation is the key to eliminating orders in area you have selected for storing your wine
  
  

• Composition of the Wine Cellar Floor
  A floor of earth or sand is important, as this also helps to reduce the level of vibrations in the room.
  
  

• Lighting of the Wine Cellar
  Lastly, the lighting must originate from unscented candles. Neon or fluorescent lighting cannot be considered as they kill wine. The candles used must be unscented as a scented candle will foul the wine.
  
  

Wine Caves
Wine caves are an integral component of the wine industry world wide. In Northern California there are an estimated 130 to 150 caves currently in use for wine aging, barrel storage, tasting rooms, and marketing events. The design and construction of wine caves represents a unique application of underground construction techniques.

The storage of wine underground offers the benefits of energy efficiency and optimum use of limited land area. Wine caves naturally provide both high humidity and cool temperatures; key to the storage and aging of wine.

The history of wine cave construction in the United States dates back to the 1870s in the Napa Valley region. Jacob Schram, a German immigrant and barber, founded Schramsberg Vineyards near Calistoga in 1862. Eight years later, Schram found a new job for the Chinese laborers who had recently finished digging and blasting tunnels and grades over the Sierra Nevada Mountains for the Union Pacific Transcontinental Railroad. He hired them to dig a network of caves through the soft Sonoma Volcanics Formation rock underlying his vineyard.

Another Chinese workforce took time away from their regular vineyard work to excavate a labyrinth of wine-aging caves beneath the Beringer Vineyards near St. Helena. These caves exceeded 1,200 ft (365 m) in length, with interior dimensions of 17 ft (5 m) in width and 7 ft (2 m) in height. In those days, the Chinese workers used pick-axes and shovels – and on the rare occasion, chisel steel, double jacks and black powder – to break the soft rock. They worked by candlelight, and removed the excavated material by hand, in wicker baskets. At least 12 wine storage caves were constructed by these methods.

Barrels
A barrel or cask is a hollow cylindrical container, traditionally made of wood staves and bound with iron hoops. Someone who makes such barrels is known as a cooper. Contemporary barrels are also made in aluminum (also called kegs) and plastic. Barrels often have a convex shape, bulging at the middle. This constant bulge makes it relatively easy to roll a well built wooden barrel on its side, changing directions with little friction. It also helps to distribute stress evenly in the material by making the container more spherical. Casks used for ale or beer are equipped with shives, spiles and keystones in their openings. The "chime hoop" is the iron hoop nearest the end of a wooden barrel. The "bilge hoops" are the hoops nearest the bulge, or center. The stopper used to seal the hole in a barrel is called the bung.

Wine barrels, especially those made of oak, have long been used as containers in which wine is typically aged. Aging in oak imparts desirable vanilla, butter and spice flavors to wine. French Oak was for many years considered especially desirable for use in constructing wine barrels. In France, Oak typically comes from one or more primary forests: Allier, Limousin, Nevers, Troncais and Vosges. The wood from each of these forests has slightly different characteristics. For example, tightly grained wood tends to impart its flavors more slowly than does that which is loosely grained. Winemakers can select wood from different forests to influence how their wine ages.

Early experiments using American Oak as well as oak from many other countries, were disappointing because the oak imparted too much flavor to the wine. It was assumed at first that the difficulty lie with the oak. However, experimentation revealed that the problem was in the preparation of the wood and the way the barrels were constructed.

Barrels Sizes
From years of experience throughout history, the optimal size of a wine barrel has evolved to be between fifty and sixty gallons. It has been found that wine barrels of smaller (or even larger) sizes than the 'standard' wine barrel do not make wines of as high quality.

Why Standard Barrel Sizes?
The ratio of the surface area to volume for a barrel is dependant on the size of the barrel. It has been found (mostly by experimentation over the years) that a fifty to sixty gallon barrel contains the optimal ratio of surface area to volume for making wine.

Coopers (Barrel Producers) - General Listings: