Vapor Barrier Advances and Why They're Important

Vapor barriers have important functions in the design and construction of a home. They can be placed on specific parts of the property during the construction portion of the building project for the best results; however, they can also be installed at a later point in time. They play a critical role in protecting the materials of the home against various types of damage. These materials can be used on the exterior or interior of the building. Some of them work best when they are installed in the deepest parts of the structure, which is only possible during construction or remodeling. 

They can also be installed on the roof, floor, siding or walls. These barriers are used during the construction stage, and they can be used in either residential or commercial buildings. They protect the home as an investment and improve the longevity of the building. There are specific methods used to determine the type of vapor barrier that is appropriate for a particular part of the property. This article covers the basic functions of vapor barriers as well as the different materials and general advancements in vapor retardant products.

Vapor Barriers, Functions

Vapor barriers function in a specific manner. They prevent moisture from diffusing through the part of the structure where they are installed. Water damage can be extremely damaging to the home, and water can take multiple forms. In addition to flood control precautions, moisture in the air can also damage critical areas of the property over time, which can affect the value of the home. The initial installation costs will save money over the life of the property because they are designed to prevent moisture damage from occurring in the first place.

The vapor barrier can have different degrees of strength, and this is an important measurement to take into consideration. There are specific tests performed on various materials, and the results are used to determine the level of permeability. This is a measurement that tells the building construction designer how much moisture will be blocked. Different areas of the building may require a vapor barrier with lower level of permeability than others. A material with a high level of permeability will block some of the moisture, but this will be insufficient for areas where there is a lot of condensation.

Types of Vapor Barriers

Certain materials are classified as vapor retarders because they allow a higher amount of moisture to cross than the materials classified as vapor barriers. The measurement for this classification is called the moisture transmission rate. Each type of material used to block moisture will have a moisture transmission rate that is expressed in a unit of measurement called a perm. The moisture transmission rate can rapidly convey essential information about the plastic, paint, vinyl coverings, plywood, plaster, glass, cement and other materials that block moisture. This information allows the builder to decide on the best material to use as a vapor barrier for a specific area of the building. Each type of material can be evaluated in terms of the best place to use it, and this can be done on the walls, floors or siding of the property.

Recent Product Advancements

Controlling moisture is essential for good home design and construction. There are many areas of the home that are vulnerable to damage from moisture and can cause structural damage, so advancements in product design become critical for minimizing the potential of water damage. Recent product improvements in concrete vapor barriers show a lot of promise, for example. Concrete is porous, and this makes it vulnerable to the condensation of water vapors, which may contain alkali. This substance is known for its ability to initiate structural damage, particularly when reinforced steel is being used in proximity to the concrete.

Vapor Barriers, Energy Efficient

Energy efficiency is a great benefit of using vapor barriers on the home's siding, floors or roof. The materials should be applied according to the specific area of the home that is vulnerable to moisture damage. Professional evaluation is often necessary in order to do this correctly. When selecting these materials, it is also a good idea to consider the additional benefits of energy efficiency. The most appropriate type of material to use in any situation will depend on factors like climate, budget and alternative options.

Common materials for vapor barriers that also improve the energy efficiency of the home include the following:

• Foam insulation
• Plastics with reinforcements
• Aluminum
• Stainless steel
• Fiberglass
• Polyethylene sheets
• Foil-backed wallboard

The best energy efficiency plan takes installation during construction into account. Extreme temperatures will require a different solution than the ones used by home construction designers in regions that experience only moderate temperatures all year long. In moderate climates, it is possible to maximize energy efficiency by using a vapor barrier that also serves as an air barrier. This solution effectively blocks the humidity and prevents it from entering the building. Humidity control is as important as temperature control because the amount of moisture in the air affects the perception of temperature. Energy efficiency is also a part of the construction process.

These materials are often placed adjacent to wooden frames, around corners and on uneven surfaces. This means that there is an opportunity for small holes or openings to appear. The presence of these defects can allow air or moisture to bypass the barrier and enter the property. Correct installation is therefore essential, and it can determine the effectiveness of the vapor barrier. Gaps will increase the amount of moisture that can cross the barrier, but they can also reduce the capacity of the heating and cooling system to work as intended. The end result is an increase in the energy usage of the building. Sealing can be performed after the fact, but it is always best to have the materials installed correctly the first time.