When it comes to maintaining a dry and healthy home, one of the most crucial components is a reliable vapor barrier. This thin layer of material plays a significant role in preventing moisture from seeping into walls, floors, and ceilings, thereby reducing the risk of mold, mildew, and structural damage. In regions with high humidity or extreme weather conditions, a vapor barrier is not just a luxury, but a necessity. With so many products available on the market, selecting the right one can be a daunting task, especially for those who are not familiar with the terminology and technology behind vapor barriers.
To help homeowners and builders make an informed decision, we have compiled a comprehensive guide to the best vapor barriers, highlighting their key features, benefits, and drawbacks. Whether you are looking to retrofit an existing building or construct a new one, our expert reviews and recommendations will provide you with the necessary knowledge to choose a vapor barrier that meets your specific needs and budget. From perforated plastic sheets to advanced membrane systems, we will explore the various types of vapor barriers, their applications, and installation requirements, ensuring that you have all the information you need to create a dry, comfortable, and energy-efficient living or working space.
We will cover the best vapor barriers later in this article. Meanwhile, feel free to check out these related products on Amazon:
Introduction to Vapor Barriers
Vapor barriers are materials designed to prevent or reduce the transmission of water vapor through walls, ceilings, and floors in buildings. They are typically installed during the construction process to control moisture and prevent damage to the building structure. Vapor barriers can be made from a variety of materials, including plastic sheets, foil-faced insulation, and specialized coatings.
The primary function of a vapor barrier is to prevent water vapor from entering the building envelope, where it can condense and cause damage. This is particularly important in climates with high humidity or in buildings that are prone to moisture accumulation, such as basements or crawl spaces. By installing a vapor barrier, builders can help to prevent mold growth, reduce the risk of structural damage, and improve the overall energy efficiency of the building.
In addition to their functional benefits, vapor barriers can also play a critical role in maintaining the health and safety of building occupants. By preventing the accumulation of moisture, vapor barriers can help to reduce the growth of mold and mildew, which can exacerbate respiratory problems and other health issues. Furthermore, vapor barriers can help to prevent the degradation of building materials, which can lead to costly repairs and replacements over time.
When selecting the best vapor barriers for a particular application, builders and homeowners should consider a range of factors, including the climate, building design, and intended use of the space. By choosing the right vapor barrier material and installing it correctly, it is possible to create a dry, comfortable, and energy-efficient building that will stand the test of time. With so many different types of vapor barriers available, it can be challenging to determine which ones are the most effective, but by doing some research and considering the specific needs of the project, it is possible to find the best vapor barriers for the job.
Best Vapor Barriers – Reviewed
The
1 – Tyvek HomeWrap Vapor Barrier
is a popular choice among builders and homeowners due to its high performance and durability. It is designed to prevent moisture from entering the walls, while allowing water vapor to escape, thereby reducing the risk of mold and mildew growth. This vapor barrier is made from a unique material that is both breathable and water-resistant, making it an ideal choice for a variety of applications.
The
1 – Tyvek HomeWrap Vapor Barrier
is easy to install and can be used in conjunction with a variety of insulation materials. It is also resistant to tears and punctures, making it a durable choice for long-term use. Additionally, it is compatible with a wide range of building materials, including wood, steel, and concrete. Overall, the
1 – Tyvek HomeWrap Vapor Barrier
is a reliable and effective choice for anyone looking to prevent moisture damage and improve the energy efficiency of their building.
The
2 – DuPont Vapor Barrier
is a high-quality vapor barrier that is designed to provide long-term protection against moisture damage. It is made from a durable material that is resistant to tears and punctures, and is easy to install. The
2 – DuPont Vapor Barrier
is also breathable, allowing water vapor to escape while preventing liquid water from entering the walls. This makes it an ideal choice for use in areas where moisture is a concern.
The
2 – DuPont Vapor Barrier
is a versatile product that can be used in a variety of applications, including residential and commercial construction. It is compatible with a wide range of insulation materials and building systems, making it a convenient choice for builders and homeowners. Additionally, the
2 – DuPont Vapor Barrier
is durable and long-lasting, providing years of protection against moisture damage. Overall, the
2 – DuPont Vapor Barrier
is a reliable and effective choice for anyone looking to prevent moisture damage and improve the energy efficiency of their building.
The
3 – Reflectix Vapor Barrier
is a unique vapor barrier that is designed to provide both moisture protection and thermal insulation. It is made from a reflective material that helps to reduce heat transfer, making it an ideal choice for use in areas where energy efficiency is a concern. The
3 – Reflectix Vapor Barrier
is also breathable, allowing water vapor to escape while preventing liquid water from entering the walls.
The
3 – Reflectix Vapor Barrier
is easy to install and can be used in conjunction with a variety of insulation materials. It is also durable and long-lasting, providing years of protection against moisture damage. Additionally, the
3 – Reflectix Vapor Barrier
is resistant to tears and punctures, making it a convenient choice for builders and homeowners. Overall, the
3 – Reflectix Vapor Barrier
is a reliable and effective choice for anyone looking to prevent moisture damage and improve the energy efficiency of their building.
The
4 – Amvic Vapor Barrier
is a high-performance vapor barrier that is designed to provide long-term protection against moisture damage. It is made from a durable material that is resistant to tears and punctures, and is easy to install. The
4 – Amvic Vapor Barrier
is also breathable, allowing water vapor to escape while preventing liquid water from entering the walls. This makes it an ideal choice for use in areas where moisture is a concern.
The
4 – Amvic Vapor Barrier
is a versatile product that can be used in a variety of applications, including residential and commercial construction. It is compatible with a wide range of insulation materials and building systems, making it a convenient choice for builders and homeowners. Additionally, the
4 – Amvic Vapor Barrier
is durable and long-lasting, providing years of protection against moisture damage. Overall, the
4 – Amvic Vapor Barrier
is a reliable and effective choice for anyone looking to prevent moisture damage and improve the energy efficiency of their building.
The
5 – Typar Vapor Barrier
is a popular choice among builders and homeowners due to its high performance and durability. It is designed to prevent moisture from entering the walls, while allowing water vapor to escape, thereby reducing the risk of mold and mildew growth. The
5 – Typar Vapor Barrier
is made from a unique material that is both breathable and water-resistant, making it an ideal choice for a variety of applications.
The
5 – Typar Vapor Barrier
is easy to install and can be used in conjunction with a variety of insulation materials. It is also resistant to tears and punctures, making it a durable choice for long-term use. Additionally, it is compatible with a wide range of building materials, including wood, steel, and concrete. Overall, the
5 – Typar Vapor Barrier
is a reliable and effective choice for anyone looking to prevent moisture damage and improve the energy efficiency of their building.
Importance of Vapor Barriers in Construction
Vapor barriers are essential components in construction, particularly in regions with high humidity or extreme weather conditions. They are designed to prevent moisture from entering the building envelope, which can lead to a range of problems including mold growth, structural damage, and reduced energy efficiency. By installing a vapor barrier, homeowners and builders can protect their properties from the damaging effects of moisture and ensure a healthier and more comfortable indoor environment.
One of the primary reasons people need to buy vapor barriers is to prevent moisture accumulation in walls and ceilings. When warm air rises and cools, it can condense into water droplets, leading to moisture buildup. If left unchecked, this can cause significant damage to the building structure, including rot, warping, and decay. Vapor barriers help to prevent this by blocking the flow of moisture into the building envelope, thereby reducing the risk of damage and maintaining the integrity of the structure.
In addition to preventing moisture damage, vapor barriers also play a crucial role in reducing energy consumption and improving indoor air quality. By preventing moisture from entering the building, vapor barriers help to minimize the need for heating and cooling, which can lead to significant energy savings. Furthermore, by reducing the risk of mold growth and moisture accumulation, vapor barriers can also help to improve indoor air quality, creating a healthier and more comfortable environment for occupants.
When selecting a vapor barrier, it is essential to choose a high-quality product that is suitable for the specific climate and building type. The best vapor barriers are designed to be durable, breathable, and resistant to moisture, ensuring that they provide long-lasting protection against the elements. By investing in a reliable vapor barrier, homeowners and builders can enjoy peace of mind, knowing that their property is protected from the damaging effects of moisture and equipped to withstand the test of time.
Types of Vapor Barriers
Vapor barriers are classified into different types based on their materials, thickness, and permeability. The most common types of vapor barriers include polyethylene, polyester, and nylon. Polyethylene vapor barriers are the most widely used due to their low cost and high effectiveness. They are available in different thicknesses, ranging from 6 mil to 20 mil, and are suitable for various applications, including crawl spaces, basements, and walls. Polyester vapor barriers, on the other hand, are more durable and resistant to punctures, making them ideal for high-traffic areas.
Polyester vapor barriers are also more breathable than polyethylene, allowing for moisture to escape while preventing water vapor from entering. Nylon vapor barriers are the most durable and long-lasting, but they are also the most expensive. They are often used in commercial and industrial applications where high performance and durability are required. In addition to these types, there are also specialized vapor barriers designed for specific applications, such as radon-resistant vapor barriers and mold-resistant vapor barriers.
The choice of vapor barrier type depends on the specific application, climate, and budget. It is essential to select a vapor barrier that is suitable for the intended use and meets the required standards and regulations. A good vapor barrier should be able to prevent water vapor from entering the building while allowing moisture to escape, thereby reducing the risk of mold, mildew, and structural damage. By choosing the right type of vapor barrier, homeowners and builders can ensure a dry, healthy, and energy-efficient building.
In addition to the types of vapor barriers, it is also important to consider the installation method and materials. A properly installed vapor barrier can make a significant difference in its performance and effectiveness. The installation method will depend on the type of vapor barrier and the application, but it is generally recommended to install the vapor barrier on the warm side of the insulation, closest to the living space. This helps to prevent water vapor from entering the building and reduces the risk of condensation and moisture-related problems.
Vapor Barrier Installation and Maintenance
Proper installation and maintenance of vapor barriers are crucial to ensure their effectiveness and longevity. The installation process typically involves laying down the vapor barrier material, overlapping the seams, and sealing the edges and penetrations. It is essential to follow the manufacturer’s instructions and recommendations for installation, as well as local building codes and regulations. A well-installed vapor barrier can help to prevent water vapor from entering the building, reduce the risk of mold and mildew, and improve the overall energy efficiency of the building.
Regular maintenance is also necessary to ensure the vapor barrier continues to perform effectively. This includes inspecting the vapor barrier for damage, tears, and punctures, and repairing or replacing it as needed. It is also important to ensure that the vapor barrier is not compromised by other building components, such as plumbing and electrical fixtures. By properly installing and maintaining the vapor barrier, homeowners and builders can help to prevent costly repairs and ensure a dry, healthy, and energy-efficient building.
In addition to installation and maintenance, it is also important to consider the compatibility of the vapor barrier with other building materials. Some vapor barriers may not be compatible with certain types of insulation, drywall, or flooring, and may require special considerations or modifications. It is essential to consult with a professional or follow the manufacturer’s recommendations to ensure compatibility and avoid any potential problems.
The cost of installation and maintenance is also an important consideration. While the initial cost of a vapor barrier may seem high, it can help to save money in the long run by reducing energy costs, preventing costly repairs, and improving the overall health and safety of the building. By investing in a high-quality vapor barrier and proper installation and maintenance, homeowners and builders can help to ensure a dry, healthy, and energy-efficient building for years to come.
Vapor Barrier Codes and Standards
Vapor barriers are subject to various codes and standards that regulate their use and installation. The International Residential Code (IRC) and the International Building Code (IBC) are two of the most widely recognized codes that govern vapor barrier installation. These codes provide minimum requirements for vapor barrier materials, installation, and performance, and are designed to ensure that vapor barriers are installed safely and effectively.
In addition to these codes, there are also various standards and certifications that apply to vapor barriers. The American Society for Testing and Materials (ASTM) and the American National Standards Institute (ANSI) are two organizations that develop and publish standards for vapor barrier materials and installation. These standards provide guidelines for the performance, safety, and durability of vapor barriers, and help to ensure that they meet minimum requirements for quality and effectiveness.
Compliance with codes and standards is essential to ensure that vapor barriers are installed correctly and perform as intended. Homeowners and builders must consult with local building authorities and follow the relevant codes and standards to ensure compliance. This may involve obtaining permits, inspections, and certifications, as well as following specific installation and testing procedures.
By following the relevant codes and standards, homeowners and builders can help to ensure that their vapor barriers are installed safely and effectively, and meet the required standards for performance and durability. This can help to prevent costly repairs, improve the overall health and safety of the building, and reduce the risk of mold, mildew, and structural damage.
Vapor Barrier Benefits and Drawbacks
Vapor barriers offer numerous benefits, including improved energy efficiency, reduced risk of mold and mildew, and enhanced indoor air quality. By preventing water vapor from entering the building, vapor barriers can help to reduce the risk of condensation and moisture-related problems, such as structural damage and pest infestations. Vapor barriers can also help to improve the overall comfort and health of the building, by reducing the risk of mold and mildew and improving indoor air quality.
In addition to these benefits, vapor barriers can also help to reduce energy costs and improve the overall durability of the building. By preventing water vapor from entering the building, vapor barriers can help to reduce the risk of heat loss and gain, and improve the overall energy efficiency of the building. This can help to save money on energy costs, as well as reduce the environmental impact of the building.
However, vapor barriers also have some drawbacks, including high upfront costs and potential installation difficulties. The cost of a vapor barrier can be significant, especially for large or complex installations. Additionally, the installation process can be challenging, especially in tight or hard-to-reach spaces. There is also a risk of vapor barrier failure, which can occur due to improper installation, damage, or compatibility issues with other building materials.
Despite these drawbacks, the benefits of vapor barriers far outweigh the costs and challenges. By investing in a high-quality vapor barrier and proper installation, homeowners and builders can help to ensure a dry, healthy, and energy-efficient building for years to come. By weighing the benefits and drawbacks of vapor barriers, homeowners and builders can make informed decisions about their use and installation, and help to create a safe, healthy, and sustainable building.
Buying Guide for Vapor Barriers
When it comes to protecting your home or building from moisture damage, a vapor barrier is an essential component. It helps to prevent the accumulation of water vapor, reducing the risk of mold, mildew, and structural damage. With so many options available, selecting the right vapor barrier can be a daunting task. In this guide, we will explore the key factors to consider when buying a vapor barrier, helping you make an informed decision.
Material and Durability
The material and durability of a vapor barrier are crucial factors to consider. A good vapor barrier should be made from a durable material that can withstand the elements and last for a long time. Some common materials used for vapor barriers include polyethylene, polypropylene, and nylon. These materials are known for their strength, flexibility, and resistance to moisture. When selecting a vapor barrier, look for one that is made from a high-quality material that can provide long-term protection.
The durability of a vapor barrier is also important to consider. A vapor barrier that is not durable may not provide adequate protection, leading to moisture accumulation and damage. Look for a vapor barrier that is resistant to punctures, tears, and other forms of damage. Some vapor barriers come with a reinforced layer that provides added strength and durability. Consider the conditions in which the vapor barrier will be used and choose one that is suitable for the application.
Permeability and Breathability
The permeability and breathability of a vapor barrier are critical factors to consider. A vapor barrier should allow moisture to escape while preventing it from entering. Some vapor barriers are designed to be highly permeable, allowing moisture to pass through while keeping air and water out. Others are designed to be less permeable, providing a more robust barrier against moisture. Consider the specific needs of your application and choose a vapor barrier that provides the right balance of permeability and breathability.
The permeability and breathability of a vapor barrier can also affect its performance in different environments. For example, in humid climates, a more permeable vapor barrier may be necessary to allow moisture to escape. In dry climates, a less permeable vapor barrier may be sufficient. Consider the climate and conditions in which the vapor barrier will be used and choose one that is suitable for the application. Look for a vapor barrier that is designed to provide optimal performance in a variety of environments.
Installation and Compatibility
The installation and compatibility of a vapor barrier are important factors to consider. A vapor barrier should be easy to install and compatible with a variety of surfaces and materials. Some vapor barriers come with a self-adhesive backing, making installation quick and easy. Others may require additional fasteners or adhesives. Consider the surface to which the vapor barrier will be applied and choose one that is compatible.
The compatibility of a vapor barrier with other materials is also crucial. For example, some vapor barriers may not be compatible with certain types of insulation or roofing materials. Consider the materials that will be used in conjunction with the vapor barrier and choose one that is compatible. Look for a vapor barrier that is designed to work seamlessly with a variety of materials and surfaces. This will ensure a smooth installation process and optimal performance.
Thickness and Weight
The thickness and weight of a vapor barrier are key factors to consider. A thicker vapor barrier may provide added protection, but it may also be more difficult to install and more expensive. A thinner vapor barrier may be easier to install, but it may not provide adequate protection. Consider the specific needs of your application and choose a vapor barrier that provides the right balance of thickness and weight.
The thickness and weight of a vapor barrier can also affect its performance in different environments. For example, in areas with high winds or heavy rainfall, a thicker vapor barrier may be necessary to provide added protection. In areas with mild weather, a thinner vapor barrier may be sufficient. Consider the conditions in which the vapor barrier will be used and choose one that is suitable for the application. Look for a vapor barrier that is designed to provide optimal performance in a variety of environments.
Cost and Value
The cost and value of a vapor barrier are important factors to consider. A vapor barrier should provide good value for the price. Consider the cost of the vapor barrier, as well as any additional costs associated with installation and maintenance. Look for a vapor barrier that is affordable and provides long-term protection. Some vapor barriers may be more expensive upfront, but they may provide added protection and last longer, making them a better value in the long run.
When evaluating the cost and value of a vapor barrier, consider the potential consequences of not using one. Moisture damage can be costly to repair, and it can also lead to health problems and other issues. Using a vapor barrier can help to prevent these problems, providing long-term savings and peace of mind. Look for the best vapor barriers that provide good value for the price and consider the potential long-term benefits.
Certifications and Warranties
The certifications and warranties of a vapor barrier are crucial factors to consider. A vapor barrier should meet certain standards and regulations, such as those set by the International Building Code or the American Society for Testing and Materials. Look for a vapor barrier that is certified by a reputable organization and meets the necessary standards. Consider the warranty offered by the manufacturer, as well as any additional support or services provided.
The certifications and warranties of a vapor barrier can also provide added peace of mind. A vapor barrier that is certified and backed by a warranty can provide assurance that it will perform as expected. Consider the reputation of the manufacturer and the quality of their products. Look for a vapor barrier that is backed by a comprehensive warranty and dedicated customer support. This will ensure that you are protected in case anything goes wrong and that you can get help when you need it.
FAQs
What is a vapor barrier and why is it necessary?
A vapor barrier is a material that prevents the passage of water vapor through walls, ceilings, and floors. It is an essential component in building construction, as it helps to prevent moisture-related problems such as mold, mildew, and structural damage. Vapor barriers are typically installed on the warm side of insulation, and they work by restricting the flow of water vapor from the interior of the building to the exterior.
The necessity of a vapor barrier cannot be overstated. Without one, moisture can accumulate in the building envelope, leading to a range of problems. For example, in cold climates, water vapor can condense on the inside of the exterior sheathing, causing mold and rot. In warm climates, moisture can accumulate in the attic or walls, leading to heat gain and energy losses. By installing a vapor barrier, builders and homeowners can help to prevent these problems and ensure a dry, comfortable, and energy-efficient building.
How do I choose the best vapor barrier for my needs?
Choosing the best vapor barrier for your needs involves considering several factors, including the climate, building type, and insulation material. For example, in cold climates, a vapor barrier with a high permeability rating may be necessary to allow moisture to escape from the building envelope. In warm climates, a vapor barrier with a low permeability rating may be more suitable to prevent moisture from entering the building. It is also important to consider the type of insulation material being used, as some vapor barriers are designed to work specifically with certain types of insulation.
In addition to these factors, it is also important to consider the durability and ease of installation of the vapor barrier. A good vapor barrier should be able to withstand the elements and last for the lifetime of the building. It should also be easy to install, with a simple and straightforward installation process. By considering these factors and doing your research, you can choose the best vapor barrier for your needs and ensure a dry, comfortable, and energy-efficient building.
What are the different types of vapor barriers available?
There are several types of vapor barriers available, including plastic sheets, foil-faced batts, and spray-on coatings. Plastic sheets are the most common type of vapor barrier and are typically made from polyethylene or polypropylene. They are inexpensive and easy to install, but may not be as durable as other types of vapor barriers. Foil-faced batts are another type of vapor barrier that consists of a layer of insulation with a foil facing. They are more expensive than plastic sheets but offer better durability and performance.
Spray-on coatings are a newer type of vapor barrier that consists of a liquid coating that is applied to the surface of the insulation. They are more expensive than plastic sheets or foil-faced batts but offer superior performance and durability. Other types of vapor barriers include fiberglass-faced batts and vinyl-faced batts. Each type of vapor barrier has its own advantages and disadvantages, and the best type for your needs will depend on your specific building requirements and climate.
Can I install a vapor barrier myself, or do I need to hire a professional?
It is possible to install a vapor barrier yourself, but it is not always recommended. Installing a vapor barrier requires careful attention to detail and a thorough understanding of building construction principles. If the vapor barrier is not installed correctly, it can lead to moisture-related problems and other issues. However, if you have experience with building construction and are comfortable with DIY projects, you may be able to install a vapor barrier yourself.
If you do decide to install a vapor barrier yourself, make sure to follow the manufacturer’s instructions carefully and take necessary safety precautions. It is also important to ensure that the vapor barrier is installed in accordance with local building codes and regulations. If you are not comfortable with DIY projects or do not have experience with building construction, it is recommended to hire a professional to install the vapor barrier. A professional will have the necessary experience and expertise to ensure that the vapor barrier is installed correctly and functions as intended.
How much does a vapor barrier cost, and is it worth the investment?
The cost of a vapor barrier can vary widely, depending on the type and quality of the material. Plastic sheets are generally the least expensive option, with prices starting at around $0.50 per square foot. Foil-faced batts and spray-on coatings are more expensive, with prices ranging from $1.00 to $3.00 per square foot. While the initial cost of a vapor barrier may seem high, it is a worthwhile investment in the long run.
A vapor barrier can help to prevent moisture-related problems and reduce energy losses, which can lead to significant cost savings over time. In addition, a vapor barrier can help to extend the lifespan of the building and reduce the need for costly repairs. By installing a vapor barrier, you can help to ensure a dry, comfortable, and energy-efficient building, which can lead to improved occupant health and productivity. Overall, the cost of a vapor barrier is a small price to pay for the benefits it provides.
Can a vapor barrier be used in retrofits, or is it only suitable for new construction?
A vapor barrier can be used in both new construction and retrofits. In fact, installing a vapor barrier in an existing building can be a highly effective way to improve energy efficiency and reduce moisture-related problems. However, retrofitting a vapor barrier can be more challenging than installing one in new construction, as it may require additional work to prepare the surface and ensure a proper seal.
When retrofitting a vapor barrier, it is essential to carefully evaluate the existing building conditions and identify any potential moisture sources or pathways. This may involve conducting a thorough inspection of the building envelope and identifying areas where moisture is entering or accumulating. By addressing these issues and installing a vapor barrier, you can help to improve the overall performance and energy efficiency of the building, while also reducing the risk of moisture-related problems. A professional contractor or builder can help to assess the building and determine the best approach for retrofitting a vapor barrier.
What are the common mistakes to avoid when installing a vapor barrier?
One of the most common mistakes to avoid when installing a vapor barrier is improper installation. This can include failing to ensure a proper seal, using the wrong type of fasteners or tape, or not following the manufacturer’s instructions. Other common mistakes include installing the vapor barrier on the wrong side of the insulation, using a vapor barrier that is not compatible with the insulation material, or not ensuring that the vapor barrier is continuous and unbroken.
To avoid these mistakes, it is essential to carefully follow the manufacturer’s instructions and take necessary precautions to ensure a proper seal. This may involve using specialized tape or fasteners, or ensuring that the vapor barrier is installed in a way that prevents moisture from bypassing it. It is also important to inspect the vapor barrier regularly to ensure that it is functioning as intended and to identify any potential problems or defects. By avoiding common mistakes and taking a careful and meticulous approach to installation, you can help to ensure that your vapor barrier functions effectively and provides long-term benefits.
Conclusion
In conclusion, selecting the right material for moisture control is crucial in maintaining a healthy and durable building structure. A well-chosen vapor barrier can prevent water damage, reduce the risk of mold and mildew growth, and improve the overall energy efficiency of a building. By considering factors such as climate, building design, and material compatibility, individuals can make informed decisions when it comes to choosing the best solution for their specific needs.
Ultimately, investing in the best vapor barriers is a critical step in ensuring the long-term integrity and performance of a building. By researching and comparing different products, individuals can find a reliable and effective solution that meets their unique requirements. Whether for residential or commercial applications, a high-quality vapor barrier can provide peace of mind and protect against costly repairs down the line. With the right information and guidance, anyone can make an informed decision and enjoy the benefits of a well-designed and well-executed moisture control system.