Gypsum Board – Uses and Benefits
The last few years have seen a range of meaningful developments in the construction landscape. The influx of technological advancements has helped curate advanced offerings that give several advantages over the traditional processes.
When you build your house or renovate it, it is common to come across people suggesting the use of gypsum plasterboards. Even though not a new finding by any means, it is only in the last few years that it has found increased traction in the construction scenario.
Gypsum boards are useful in building lightweight and durable walls.
Even though we are seeing increased use of synthetic gypsum plasterboards, the traditional ones use dehydrated calcium sulfate and convert it into CaSO4.0.5H20 by heating it.
Once dehydrated, the resulting product is mixed with several additives and water. It is then placed onto cardboard running on a conveyor belt. It soon takes the shape of a needle-like structure that combines to form what we commonly know as gypsum plasterboards.
This article delves into the subject and discusses the types, properties, and applications of gypsum plasterboard.
What is gypsum plasterboard?
As per ASTM C11, the gypsum board is “the general name for a family of sheet products consisting essentially of gypsum.”
Also known as plasterboard or drywall, the gypsum board is a technical name given to a plaster-based wall finish that helps in creating light walls. Even though it is an umbrella term, all of its types use gypsum, a non-combustible core, and paper surface covers them.
Once it goes through a joint treatment system, it can create a monolithic structure, built to last.
Gypsum board sizes
You are likely to find gypsum plasterboards of different sizes in the market. Each of these sizes caters to a different purpose. You must choose the optimum size as it will allow you to minimize cost without compromising on quality.
Here are the different size specification for a gypsum plasterboard that you are likely to find –
¼-inch (0.635 cm)
The ¼-inch gypsum plasterboard is a low-cost structure dedicated for use in ceilings, improving existing walls, curved surfaces, and improving sound control. It mainly finds use in home décor.
3/8-inch (0.9525 cm)
The ⅜ -inch gypsum plasterboard finds usage primarily as a face layer for remodelling or repair purposes. These are applied over wood framing and usually in a double-layer format.
½-inch (1.27 cm)
The ½-inch variant is used primarily in single-layer wall systems. It is excellent for soundproofing and fire protection and is more likely to be found in residential buildings.
5/8-inch (1.5875 cm)
The ⅝ -inch variant is one of the thicker versions. It helps in improving resistance, rigidity, and higher fire resistance. These characteristics make them excellent for single-layer and double-layer walls.
¾-inch (1.905 cm) and 1-inch (2.54 cm)
The ¾-inch and the 1-inch variant are used for creating shaft walls, partitions, corridor ceilings, and similar purposes. These are the thickest gypsum plasterboard available and offer the highest resistance.
Gypsum plasterboard types
1. Drywall white board or gypsum board
The drywall whiteboard refers to the standard variant. It is useful in creating false ceilings, and also finds usage as a covering material in places with no specific needs.
These are painted white on one side and brown on the other.
These range between 3/8-inch to 1-inch and offer basic fire protection, but have no additives to improve the resistance.
2. Backing gypsum plasterboard
The backing plasterboard is a combination of several layers of drywall and is available in ¼-inch to 1-inch thickness. Such a formation has diverse use cases, such as for walls, ceilings, self-levelling screeds, and partitions.
The backing gypsum board has grey liner paper on its front and back and offers improved sound control, strength, and fire resistance.
3. Moisture-resistant gypsum plasterboard
Also known as green boards, the moisture-resistant gypsum drywall comes with a green covering.
The added layer reduces the impact of moisture on it. But if you plan to use it for places with frequent water contact, we would caution you that these are not completely waterproof. Exposing these to water continually will cause erosion.
These are costlier than the regular variant and find usage in kitchen space, laundry rooms, and basements.
4. Modified moisture-resistant gypsum plasterboard
If you are looking for better moisture resistance and better characteristics, you can opt for purple or the modified moisture-resistant gypsum plasterboard. It also offers superior mold protection, making them perfect for kitchen and bathroom settings.
5. Blue board gypsum board or plaster baseboard
The blue board gypsum board or plaster baseboard comes with a surface layer that has superior absorption abilities.
It has limited use cases and is primarily used for veneer plastering.
The modified variant offers high mold and water resistance, making it ideal for use as partition boards. These work superbly in bathrooms and kitchens but are not great against mud, paint, and taping materials. The board has a high thickness, enabling it to reduce sound inflow too.
6. Paperless gypsum plasterboard
These are the improved variants of the regular gypsum plasterboard version. As the name suggests, the paperless board does away with paper and replaces it with fibreglass.
The result?
These offer higher resistance against mold and are more durable too. These are easy to cut, making them an excellent option for a variety of use cases.
7. Fire-resistant gypsum plasterboard
The fire-resistant gypsum board offers excellent protection against fire hazards. It contains non-combustible fibres that improve their propensity towards the fire. However, these are thicker and more difficult to cut and give the requisite shape. We often find them in a commercial setting.
8. Soundproof gypsum plasterboards
The regular variant offers sound protection to a certain degree. But if you are looking for more, you can opt for a soundproof gypsum board with acoustic features for your walls.
These specialize in complete sound absorption and comprise a combination of wood fibres and polymers, along with gypsum. These are ideal for acoustic needs like music rooms or ambiences that require high sound suppression.
The soundproof gypsum plasterboard is denser and difficult to cut and shape.
9. Exterior gypsum soffit board
Unlike most other types, the exterior gypsum soffit board is designed for outdoor usage. These are available in ½-inch or 5/8-inch thickness and are found on the undersides to prevent unwanted indirect weather exposure.
Properties of gypsum plasterboard as a building material
The material gypsum has a plethora of inherent properties that make it an excellent option for construction. Here are the properties of gypsum plasterboard as a building material –
1. Fire resistance
With gypsum being a fire-resistant material by itself, gypsum plasterboard can also hold fire for up to four hours. The reason behind it is the presence of water in gypsum offerings. When the water comes in contact with the fire, it starts evaporating. It helps the board to develop a protective layer that helps to prevent fire from spreading for some time.
2. Non-combustible
When the gypsum board comes in contact with fire, it initiates a process called calcination. Calcination refers to the process of dehydration of the board, helping it develop an additional layer. It makes the wall to be non-combustible for a few hours and also maintains normal temperature throughout.
3. Acoustic properties
Gypsum plasterboards are inherently soundproof to an extent. These are more effective compared to the traditional walls of the same thickness. It is because these contain a sound break and reduce reverberation.
For example, a gypsum plasterboard of around 60mm is as effective as a masonry wall of 85mm in blocking sound. Users also get an option of using soundproof drywall which further improves the performance.
4. Thermal properties
Drywalls have crystal water in them. They also incorporate cavities, allowing users to have the right balance of humidity and temperature. If you include fibreglass, it would further prevent fire as fibreglass helps in keeping the integrity of the board. The extra insulation helps to manage indoor humidity by acting as a vapour barrier.
Advantages of gypsum plasterboards
Gypsum plasterboard has been known to provide a superior finish compared to several other finishes. Here are the advantages that it offers:
Lesser shrinkage cracks
A gypsum plasterboard is less prone to producing heat compared to cement when mixed with water. So once it hardens, there are lesser shrinkage cracks.
Easily manageable
Drywalls do not command separate finishing, i.e., you can apply them directly over any base, such as AAC blocks, solid or hollow blocks, bricks, and plasterboards. It is also easier to apply and level them.
Eliminates curing time
Unlike cement and water combination, the new-age boards do not require curing time. It helps you save time and water during the construction phase.
Superior finish
Drywall offers perfectly aligned, levelled, smooth surfaces that are superior to the traditional cement-water combination, which requires post-processing for the same.
Enhances setting time
A cement-based plaster must dry properly for a few days before you can carry on the painting process. Drywall sets within half an hour, enabling you to begin painting within three days of application.
Excellent durability
The application of gypsum plasterboard reduces the dead load on the structure and ensures a highly durable structure once it dries.
Low supervision requirement
The traditional plaster requires mixing cement, sand, and water in proper proportions. It means that there is a constant need for supervision to ensure that the mix is usable. But gypsum plasterboard does not require continual checks and reduces the time spent in supervision.
Fire and sound resistance
The drywall structure offers superior resistance against fire and sound, making it a better alternative compared to traditional plaster.
Applications of gypsum plasterboard in the construction
It was in the year 1988 that people experienced the use of gypsum as a building material. The American Augustine Sackett developed a machine capable of producing drywalls that had paper and gypsum in between.
Today, we use gypsum plasterboard for both residential and non-residential buildings. It includes using them for construction and refurbishing purposes. The ability of it to be highly ductile and also have a plethora of useful characteristics has been instrumental in its growing popularity.
In Europe, over 1500 million square meters of interior surfaces get gypsum-based covering (blocks or plasterboard).
FAQ on gypsum plasterboards
What are gypsum plasterboard ceilings?
It is a false one made of gypsum plasterboards. These are easy to install, clean, and maintain.
Is the gypsum plasterboard good for the ceiling?
False gypsum board ceilings are long-lasting. In normal circumstances, these will last over 20 years with minimum maintenance requirements.
What is the standard size of the gypsum plasterboard?
Usually, the length lies between 1800mm to 4500mm. If you need a customized one, you can order one with different dimensions.
Is the gypsum plasterboard waterproof?
Gypsum plasterboards also come in a waterproof variant. Even otherwise, these do not intake too much water and offer a certain level of water resistance inherently.
Can the gypsum plasterboard be painted?
Users can paint the surfaces after applying a coating of a drywall primer. The primer would help level the surface and ensure smooth paint application.
Can we use a gypsum plasterboard in a bathroom?
The regular variant is not a good fit for side bathroom walls. But green drywall, the mould-resistant one, or the purple board, can be used for locations that are in constant contact with water, such as bathrooms and kitchens.
How do you maintain the gypsum plasterboard?
Gypsum plasterboard is an excellent option for indoor purposes. It requires no additional maintenance. You can use the regular rug or broom to clean it. Unless you are using the waterproof drywall, make sure that you don’t use water for cleaning it.
Is gypsum plasterboard bad for health?
No. There are no health-related hazards linked with its application. It is not classified as “dangerous” as per EU CLP regulations. If you somehow ingest gypsum, drink plenty of water after washing your mouth thoroughly.
What is the average moisture level in the gypsum plasterboard?
In usual circumstances, moisture content of 5-12% is considered best. If it is over 12%, it means that you will have to replace it.
What is a purple board?
Purple board or purple gypsum board is a modified variant offering better resistance against moisture, mold, and mildew. It is effective for places prone to high moisture content. A purple board comprises two thin sheets of plasterboard with a thin elastomer centre in between. It also offers better soundproofing.
What is the right drywall thickness for my ceiling?
If you are using drywall for ceilings, 5/8-inch is the most appropriate size. These reduce sagging chances while being lightweight and offering good heat resistance.
Concluding remark: gypsum plasterboards are an excellent replacement for traditional plaster
Traditionally, gypsum plasterboard is costlier than cement-based plaster. But they offer superior resistance making them a more viable option for long-term usage. The availability of synthetic gypsum created as a by-product of industrial processing has helped keep the cost in check while offering the same characteristics.
It has also allowed better usage of waste, helping to keep the environment clean. Gypsum plasterboard is also considered easy to recycle and is one of the rarest examples of closed-loop recycling, i.e., using the waste to make the same product multiple times over. It is the reason these are considered ‘green’ for the environment.
