A cement board is a combination of cement and reinforcing fibers formed into 3 legs with 5 legs, 1/4 to 1/2 inch thick, typically used as a tile board. The cement board can be nailed or screwed into wood or steel studs to create a substrate for vertical tiles and attached horizontally to plywood for tile floors, kitchen counters and backsplash. Can be used on the exterior of the building as a basis for exterior plaster system (plastering) and sometimes as the finish system itself.
The cement board adds resistance and impact strength to the wall surface compared to the waterproof gypsum board. The cement board is also made in a thin sheet with a modified cement polymer to allow bending for curved surfaces.
Video Cement board
Composition
Cement board is mainly particle board of cement cement and cement fiber.
The cemented bonded particle board has processed wood chips as reinforcement, while the cement fiber board has cellulose fiber, which is a plant extract as a reinforcer. Cement acts as a binder in both cases. The fireproof properties of blue particles bonded with cement and cement fiber boards are the same. In case of load-bearing capacity, the cement-bonded particle board has a higher capacity than the cement fiber board. The cement particle board is made from a thickness of 6 mm to 40 mm making it suitable for high load bearing applications.
It is made of a homogeneous mixture and is therefore formed as a single layer for each thickness. Cement fiber board is more widely used in decorative applications and can be made from 3 mm to 20 mm thickness. Fiber boards are made in very thin layers, making it very difficult to make high-thick boards. Many manufacturers use additives such as mica, aluminum stearate and cenospheres to achieve a certain board quality. The typical cement fiber board is made from about 40-60% cement, 20-30% filler, 8-10% cellulose, 10-15% mica. Other additives such as aluminum steer and PVA mentioned above are usually used in amounts less than 1%. Cenospheres are used only in low density boards with quantities between 10-15%. The recipe actually depends on the available raw materials and other local factors.
Maps Cement board
Benefits
As a tile support board, the cement board has a better long-term performance than a paper-faced gypsum core product because it will not be moldy or physically damaged if there is continued moisture or leakage. The cement board is actually not waterproof, but very resistant to absorb moisture and has excellent drying properties. In areas continuously exposed to water spray (ie rain), waterproof barriers are usually recommended on the back of the board or as a product applied to the front shovel board behind the finish system.
Disadvantages
One major disadvantage of the cement board is the weight per square foot. This is roughly double that of the gypsum board, making handling by one person difficult. Cutting the cement board should also be done with a carbide-tipped tool and a saw blade. Due to its hardness, pre-drill fasteners are often recommended. Finally, cement boards are initially more expensive than waterproof gypsum boards but can provide better long-term value.
Installation
The cement board is hung with stainless screws or ring-shank nails. Cement boards have very little movement under heat pressure, but boards are usually fitted with little gaps in joints in bathrooms, bathtubs, and each other. These joints are then filled with a silicone sealant or taping compound maker before applying the final result. The filled joint is affixed like a conventional gypsum board, but with fiberglass bands that provide additional water resistance. Combined with a waterproof coating, the cement board is a stable and durable backing board.
Water resistant
The category of construction material known as cement board includes waterproof and waterproof board. Each has its own best use.
Usually waterproof cement boards consist of a gypsum core that is treated with an inorganic fiber reinforced layer, either on one or both faces. This type of board requires fast sealing of all cutting edges and penetrations to maintain a factory warranty for wet area installations. Gypsum core "cement" board panels are ideal for moist mountings but are not completely wet from tiles and/or stone walls.
There are classes of cement boards that are completely built from Portland-based cement cores by reinforcing fiber glass mats on both faces. These panels can be immersed in water without any degradation (excluding the freeze thaw cycle). These panels do not require edge sealing and penetration to maintain their structural integrity. These Portland cement based products are smaller in size compared to gypsum-based products. Usually the size starts from 30 "x 48" to 36 "x 60". They are, as expected, much heavier than gypsum core type panels.
Portland cement based panels are ideal for truly humid locations such as surrounded showers and for locations where Portland based cement based materials are used to bind tiles and rock surfaces to the substrate. They are also ideal for mounting floor and stone tiles on top of structural subfloor.
Cement board can be classified as waterproof because it is not affected by exposure to water; However, they allow penetration and parts of water and moisture. For waterproof cement boards, waterproofing fluid or membrane materials are applied over the surface.
The cement board should not be confused with the gypsum core backing board. The gypsum core support board is affected by water and should not be used in the wet exposure area.
See also
- Drywall
- Fiber cement
- Cement fiber plate
- Clay Panel
References
External links
- Why is the Cement Replacement Board Extremely Large? (And What It Is Using To! By Lee Wallender, About.com
- iVillage Home & amp; Garden Network, What it has and the cons of Wonderboard vs. Hardybacker
- National Gypsum PERMABASE BRAND CEMENT BOARD
Source of the article : Wikipedia
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