Wine storage rooms are more than a dark, cool place to stock a collection of wine bottles. Today's custom wine cellar is a controlled environment where humidity and temperature are regulated to allow wine to accurately age without harm to corks, labels or the wine itself.

There are two types of wine cellars. One is an area that has been especially built to stock wine in the perfect environment and the other is a stand-alone system that copies those conditions. A stand-alone wine cellar is not as efficient as a custom-built version, but some people like the aesthetics of a small cooled refrigerator over a custom wine cellar. Those who do choose a custom cellar have three simple considerations for proper build-out.

Temperature Control and Venting

A wine cellar room is used to hold and age the wine in the bottle rather than preserving it at a serving temperature. (A stand-alone wine fridge is best for carrying wine out of the cellar to store at serving temperatures.) Maturing wine is a balance of time, temperature and the chemical reactions that occur as an effect of the two.

Wine should be matured in conditions ranging between 55 and 65 percent humidity and a solid 55 degrees Fahrenheit, give or take one degree. Wine held at higher temperatures will age sooner and wine experiences chemical reactions at higher temperatures that spoil the flavor over time.

In some locations of the country, property holders with basements often find that the environment is right for basic wine storage, but seasonal temperature and humidity variations should be avoided. The ideal storage solution is a custom-built or DIY-construction wine cellar with climate and humidity control using a wine cooling component to keep the temperature at a stable 55 degrees.

These components come in an array of sizes and the dimensions of your wine cellar will dictate what size you need to purchase. By no means select a wine cellar cooler too small for your room; you may never get an accurate, optimal storage temperature and the cooling system will become overtaxed trying to keep up.

Wine cellar cooling systems require proper venting, and your wine cellar construction plan requires either a hole in the wall to permit venting outdoors or enough vent space to move warm air out of the room. Check the specs of your wine cooling unit; most call for a venting space at least two times as large as the wine room space itself.

Electrical power is also an issue. Custom wine cellar builders suggest a devoted power source to run a wine cellar cooling system. Those who choose to use a common power source frequently find the system overloading with blown fuses and other electrical issues.

Insulation and Vapor Barriers

The wine cooling unit is only part of your climate control plan for a custom wine cellar; you also need a vapor barrier made of plastic sheeting used on the “hot” side of the wall. Some people enclose the interior of the wine cellar previous to inserting the insulation, leaving the plastic loose so that insulation can be positioned between the studs in the wall. Cover the ceiling and the walls, or your vapor barrier will be imperfect. Once the barrier is installed, the insulation will come next.

Good wine cellar construction needs the right kind of insulation for your walls and ceiling. For instance, if you are building a 2x6 wall, R19 insulation is recommended, but if you have a smaller wall of 2x4, R13 may be your best bet. (The “R” designation represents the heat resistance of the insulation.) Ceilings require R30. Custom wine cellar builders should never set up the insulation loose without filling the material into the sections, as this decreases the insulation's effectiveness.

The next step is to install a kind of drywall called green board, which is moisture-resistant, making it a bit more expensive than regular drywall. Install an exterior-grade door to the wine cellar and your climate control plan is finished.

Lighting and UV Exposure Control

Wine is damaged by UV exposure, which is why the bottles are normally constructed out of dark glass. Stay away from installing fluorescent bulbs in the wine cellar room, as they give off UV radiation. Control the strength by using recessed lighting on a dimmer and avoid shining light straight on your wine bottles for long periods of time. Some wine racks are constructed with sections that hide bottles from the light which can help reduce exposure, but if your bottles are stowed in plain view, try to avoid the “spotlight” effect on your bottles.

Other Concerns

Nearly any sort of flooring can be used in your custom wine cellar. If your home is big enough for a wine cellar tasting room to complement your cellar, you may wish to give them both an identical look, but never use carpet and rugs in the cellar area. They simply can't hold up to the required humidity levels without giving away to mold. Mold growth will destroy your wine, as can any potent odor from chemicals or cheeses. A wine cellar should be used only to store wine; keep food in a different space.

At all times check the temperature and humidity in your wine cellar with an external sensor or gauge. By no means guess that the wine cooling component will always work properly. A quick look at the external gauge can give you early notice if the wine cooling system is having problems, or if the unit is giving a faulty readout because of a bad sensor or other technical issues.

Constructing a custom wine cellar room may require some attention to the design demands of good wine cellar storage, however once correctly built, you may realize that your collection grows quickly; it's easy to invest more money in wine when you realize it will be held securely for maximum enjoyment.