Drywall, (also known as plasterboard, gypsum board, sheetrock, rock, or lath) is a panel made of gypsum plaster pressed between two thick sheets of paper. The sheets of the drywall can be made from fiberglass instead of paper to prevent mold growth. Mold growth is common when using paper-based plasterboard that has been exposed to water due to plumbing leaks or floods.
To manufacture drywall, raw gypsum is mixed with several additives, including starch, paper pulp and an emulsifier (or thickening agent), then blended with water to form a thick paste. The gypsum paste is spread onto Manila paper in 3/8-inch to 3/4-inch thick layers. Another sheet of Manila paper is then laid on top. The entire formation passes through ovens that heat the sheet at temperatures up to 500 degrees. This dries the plaster out and prepares it for cutting. Typical sheets are 4x8 feet, though 4x10 feet and 4x12 feet sheets have become popular recently, as they allow for faster installation of taller walls.
Believe it or not, despite being used to make “dry” wall, there's a large amount of waterin gypsum. The water is in crystalline form, which is why the individual molecules of gypsum are dry. These crystalline water molecules give finished drywall itsfire resistance. As drywall gets hot, the water crystals begin to destabilize and begin vaporizing as the water reaches its boiling point. The evaporating water crystals keep the drywall cool, protecting the structure behind it.
The drywall market is booming and continues to rise. The United States and Canada together possess the greatest number of drywall users in the world. The drywall market is booming and continues to rise. Drywall is the material for all seasons. This material provides protection and lightweight support and adds an attractive appeal to the home.
There are many types of drywall. White board is the basic regular drywall. This form of drywall looks appealing, is the cheapest, and is used for those who need either a quick-fix or wish for a nice appearance at a very cheap price.
Fire-resistant “Type X” is a bit more expensive for obvious reasons. This form of drywall holds up better, although it has its drawbacks as well.Thickness of the drywall is obviously a factor. Thicker drywall will provide more fire protection. There is also another type of drywall, sometimes calledfirewall, which will provide even greater fire resistance. Type X firewall has fiberglass added and increases the fire rating per thickness of the sheet. It actually helps maintain the structural integrity of the firewall when it is exposed to high temperatures. Type X firewall 5/8-inch thick on both sides of a 2X4 studded wall should provide about 1 hour of fire protection. Type C firewall has even better fire protection.
Greenboard drywall contains an oil-based additive to the green-colored paper covering that provides resistance to moisture. Typically greenboard is used in high humidity areas such as bathrooms, or laundry rooms. Green Board is sometimes installed instead of concrete backer board around bathtubs but it should only be installed where direct water contact is not normal. When we say direct water contact, that means walls that have not tiled too. Also know that grout does and will fail over time, and you can also have water seepage around fixtures or any place there is a puncture in the surface. Green Board should be used on all of the walls including the ceiling in your bathroom.
Concrete backerboardis a more water resistant drywall than greenboard, and is used any place that direct water contact could occur and in areas where tile will be installed. This material comes in smaller sizes then standard drywall and it comes in two standard versions.
The first is standard concrete board and this material is gray and looks like concrete has been used to form a section of drywall. The second is a higher processed material and is yellowish in color and very uniform in appearance. Concrete backer board used to build shower stalls or bathtub surrounds should always be used in conjunction with vapor barriers and rubber membranes.
(Water Resistant Drywall / Green Boardare sometimes installed instead of concrete backer board around bathtubs, but it should only be installed where direct water contact is not normal. When we say direct water contact that means walls that have been tiled too. Grout does and will fail over time and you can also have water seepage around fixtures or any place there is a puncture in the surface. Green Board should be used on all of the walls including the ceiling in your bathroom.)
Most drywall installers will tell you it is only necessary to install greenboard or water resistant drywall within a few feet of a shower or tub, but the cost difference is so insignificant and the benefit is much greater. This means that the only reason not to use it in a bathroom with a shower or tub, is only a cost cutting measure for the contractor, and they do not have your best interest at heart. Bad contractors that recommend doing this, (They) know they can get in and out quickly, and everything will be fine for a while. The fact is, they would use the correct drywall on every wall in their own home, so why not yours?
Paperless drywall is a newer type of drywall that also has many advantages. The biggest being is that it is mold resistant, and helps to minimize the spread of mold. The fiberglass covering on paperless drywall is not a food source for most common molds, therefore mold development is more challenging, and paperless drywall is more unresponsive to mold growth. Another plus to paperless drywall is that the surface is more damage resistant and tougher, making it more resistant to dings, nicks and dents. When installing standard drywall in areas of moisture, such as bathrooms, laundry rooms, basements, a vapor barrier should be installed, and with paperless drywall there is no need for a vapor barrier. The primary installation areas for paperless drywall seem to be in bathrooms, kitchens and laundry areas. There is a slightly rougher surface when you view paperless drywall from a closer view, however from a distance of approximately 5 feet away, you cannot tell any difference between standard and paperless drywall. When a light is cast on paperless drywall you can sometimes see the texture of the fiberglass matting. It does take an experienced and qualified drywall finisher to install paperless drywall and the entire surface of the paperless drywall should be skimmed with a drywall compound. Also, keep in mind there are different methods of skim-coating and different tools to use, so it is important again to make sure you are using an experienced drywall finisher. Paperless drywall is not for the “do-it yourself project”.
High Impactdrywall is composed of fiberglass mesh embedded in the core close to the back side of the board, thus providing additional impact resistance. High impact drywall is made using purple paper. It is generally at least 5/8 inch thickness, although it may appear thicker due to the fiberglass layering on its back. High Impact drywall is used primarily in buildings such as schools, hospitals, dormitories, and correctional facilities where wall damage and penetration due to high traffic may be encountered. Because of its fire resistance rating, it is typically used in areas requiring fire-rated separation.
Supress® Sound-Engineered Drywallis a soundproofing drywall that is composed of a core encased in heavy natural-finish paper. Supress is commonly used residentially in floors, ceilings and walls for home theaters, studios, media rooms, music rooms, and children's rooms.
"Design is not making beauty, beauty emerges from selection, affinities, integration, love."
- Louis Kahn
