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  • Why a vapor barrier is important for your wine cellar.

What is a vapor barrier?

Basically, a vapor barrier creates a separation between the environment outside your wine cellar and the environment inside your wine cellar. While it doesn’t prevent the warm air in your home or business from traveling to the cooler environment in your wine cellar (insulation does that), it plays an important role overall in controlling the environment. Your wine cellar needs to have the ambient temperature lower than the area outside it. A vapor barrier is critical to controlling the humidity in your wine cellar.

Why is creating a vapor barrier important?

To understand why a vapor barrier is important, you need to understand what happens when there is an imbalance between warm and cold. Picture driving your car in very cold weather. Naturally, you turn on the heat to warm up your vehicle’s interior, and what happens? Your windshield fogs up with moisture. Now that that same concept and apply it to your wine cellar. When you try to make wine room cooler than the rest of your home or business, the moisture or humidity from the warmer area (your house or restaurant) will condensate upon contact with the much cooler area (your wine cellar). Without the right barrier to separate the two opposing environments, condensation will build-up.

Do all wine cellars need vapor barriers?

The short answer is yes. Any climate-controlled wine cellar needs vapor barriers, regardless of what kind of location you’re in. If you’re going to refrigerate a wine room, you need insulation, and if you’re going to have insulation, you need a barrier. In humid climates, this prevents warm, moist air from entering the cellar, which can cause mold. In dry climates, this helps to regulate the humidity within the cellar. Vapor barriers are typically installed between the foundation wall and the insulation. The vapor barrier belongs on the outside of the wine room!

While there are several options for insulating, closed-cell foam is the best way to insulate and vapor barrier your wine cellar. The advantage of using closed cell foam (polyurethane) is that when it skims over, it forms its vapor barrier. There is no need to install plastic sheeting as other options may require. Closed-cell spray foam expands and fills all the cracks and crevices leaving no gaps and if there is any wiring, conduit, or piping that goes through the cellar wall, spray foam creates a tight seal around it, so there is no potential for vapor to penetrate the material.

What can happen if a wine cellar doesn’t have a vapor barrier?

When a wine room lacks a vapor barrier or the barrier is not properly installed, condensation can form potentially dampen the insulation and form mold. Too much condensation can also threaten the integrity of the cellar walls and make the cooling system work harder to keep the air inside the cellar at the proper humidity level, eventually causing it to burn out. You want to ensure that moisture never reaches the cool surface.

The best way to ensure that your wine cellar is properly insulated is to work with a wine cellar installation professional such as Heritage Vine. They’ll be able to evaluate the space where your wine cellar is being built, suggest installation and vapor barrier options, and provide you with the best recommendation to keep your climate-controlled wine cellar running properly. If you’re considering adding climate control to an existing wine room, engage the assistance of a company offering wine cellar cooling services to protect your wine cellar.

What would you like to create?
