Green board drywall is a popular moisture-resistant drywall. Manufacturers have developed green board drywall to address the challenges of high humidity and occasional water exposure on interior surfaces. Green board drywall is not water-proof, but its unique water-resistant properties give it added protection against all water-related problems, including mold, mildew, and corrosion.
The distinctive green paper color distinguishes green board drywall from standard drywall, serving as a visual reminder of its moisture-resistant properties. Understanding the qualities, benefits, and best practices surrounding green board will allow you to utilize this valuable resource in your home construction projects.
What is green board drywall?
Green board drywall is a type of gypsum wall panel that manufacturers design to withstand high levels of moisture and water exposure. Builders typically use it in high-moisture areas like bathrooms, kitchens, and basements.
The term “green board”, also written as “greenboard”, refers to the distinctive green color of the panel due to the green paper facing on one side. The face of this green paper is treated with a wax additive that makes it more resistant to moisture absorption. This treatment helps protect the paper from growing mold, mildew, and corrosion from water. Green board drywall has a standard gypsum core that gives it natural fire resistance.
Using Green Board Drywall vs. Standard Drywall
Green board is especially useful in moisture-prone areas of the home. Its unique qualities make it a good choice in these rooms.
- Bathroom – Due to the presence of moisture from sinks, showers and bathtubs, bathrooms are ideal for green board drywall versus standard drywall. Installing green board drywall will prevent mold and mildew growth from high humidity.
- Kitchen – The kitchen is another high humidity area because of the potential for water splashes and leaks. Green board can add drywall protection to ensure your walls won’t deteriorate with water exposure.
- basement- Being underground, basements tend to have high humidity levels. Green board drywall can help reduce the growth of mold and mildew common in basement rooms.
- Laundry Room – Laundry room subject to spills and leaks. Green board drywall offers better defense against potential water exposure.
- Utility Room – Utility rooms that have water heaters, utility sinks and boilers can suffer from water leaks. To better protect against them, add green board drywall instead of standard drywall.
- garage – Garages can benefit from green board drywall if you use them as a multipurpose space that has water exposure.
- Crawl Space – Crawl spaces are located below the ground surface and are prone to high humidity. Using green board drywall will protect the walls from corrosion.
Cost of green board drywall
Green board drywall is more expensive than standard drywall because of its specialized materials and manufacturing. Standard drywall costs $0.40-0.50 cents per square foot. Green board drywall costs between $0.50 and 0.70 cents per square foot. A standard 4 ft. x 8 ft. green board drywall panel costs between $12-20 dollars, depending on the supplier and location. Sometimes, building supply stores will offer bulk discounts for orders of more than 48 sheets of drywall.
Green board drywall size
Green board sizes are similar to drywall Standard drywall sizesDiverse to accommodate projects of varying scope.
length and width
- 4′ x 8′ sheet – Green board is the most common size for drywall panels. Builders use it to build walls.
- 4′ x 10′ sheet – These sheets are 4 feet wide and 10 feet long. Longer panels are useful in larger rooms and to reduce the number of seams.
- 4′ x 12′ sheet – 4′ x 12′ sheets are not common but are useful for walls in rooms with high ceilings or where seam reduction is required.
- special sizes – Other sizes are possible but not common. Availability will depend on specific manufacturer and region.
- ½” – ½” thick sheet green board is the most common standard thickness for drywall. It is suitable for most interior walls and offers a good balance between strength and versatility. This thickness provides good moisture resistance.
- ⅝” – This sheet is primarily used in commercial spaces where additional moisture resistance, fire resistance and strength are required.
Limitations of green board drywall
Green board drywall isn’t the answer to all your moisture-related concerns. It has limitations for its use that you need to consider before choosing it for your project.
- Not waterproof – A major misconception people have about green board is that it is waterproof – it is not. It is more moisture-resistant than standard drywall and can handle occasional water exposure, but is not suitable for areas with direct and constant water exposure. In areas such as shower enclosures or other wet areas, use cement backer board or water-proof membrane as a sublayer.
- Limitation to high humidity areas – Green board is moisture-resistant. But in areas exposed to constant humidity, they may suffer some negative effects depending on the humidity level.
- Mold and mildew – Green boards have a thick and waxed paper face that prevents water from penetrating the gypsum core, but they are not specially treated to prevent mold and mildew growth. If water reaches the roots and doesn’t have a chance to dry out, mold and mildew can develop. Newer varieties of mold and mildew-resistant drywall are a good option if your area is constantly exposed to moisture.
- cost – Green board drywall is more expensive than standard drywall because of its treated paper facing. Although not a huge difference in cost, the higher cost will have a greater impact on larger scale projects.
- A false sense of security – Relying on green board instead of addressing the underlying problem or installing it in areas with excessive water can cause damage over time. Before installing green boards it is important to ensure that your overall plan and construction methods are correct to manage moisture.