During interior finishing, it's common to choose between calcium silicate board and gypsum board. What are the differences between these two materials? What are their material properties? And where are they commonly used?

The following will be an explanation for designers by the Craft Society and Environmental Design Institute of HJSJ on the differences and practicality of calcium silicate board and gypsum board!

Analyze based on material composition, fire resistance rating, usage location, price, specifications, and thickness.

1. Material Properties:

Gypsum Board
Gypsum board is made from gypsum plaster as the main raw material, with paper faces on both sides and gypsum in the middle. The paper layer serves to reduce cracking caused by the brittleness of gypsum itself. Various types of paper surfaces are used to provide different functionalities.
Currently, there are gypsum boards available with features such as moisture resistance, water resistance, and fire resistance.

Calcium Silicate Board
Calcium silicate board is a building material made from siliceous materials (mainly SiO2, such as quartz powder, fly ash, diatomite, etc.), calcareous materials (mainly CaO, such as lime, carbide slag, cement, etc.), reinforcing fibers, and additives. These materials are mixed in specific proportions, then processed through pulping, molding, and steam curing. Currently, asbestos-free calcium silicate boards are available on the market.

2. Fire Resistance Rating:

Calcium silicate board is more fire-resistant than gypsum board.

Gypsum board is classified as B1 grade fire-retardant material. During the early stages of a fire, it may emit smoke and gases.

Calcium silicate board, with both its outer and inner layers made of inorganic materials, has an A-grade fire resistance rating. It is a non-combustible material and will not release toxic gases during combustion.

3. Usage Location:

Calcium silicate board has a broader range of applications than gypsum board. Both calcium silicate board and gypsum board can be used for ceiling decoration and wall partitioning. Due to its excellent fire resistance and durability, thicker calcium silicate boards can be used for fireproof ducting and pipe coverings.

4. Ease of Installation:

Gypsum board is easier to install than calcium silicate board.

Calcium silicate board is difficult to process due to its harder material. It is harder to cut during installation and generates a lot of dust. Calcium silicate board cannot be used for curved shapes.

5. Price:

Calcium silicate board is more expensive than gypsum board.

The price is influenced by factors such as region, brand, and materials. Taking a first-tier city as an example:

For a specification of 2440×1220×8mm, a well-known brand of standard calcium silicate board costs 45-70 RMB per sheet.

For a specification of 1200×2400×9.5mm, a well-known brand of paper-faced gypsum board costs 25-45 RMB per sheet.

6. Specifications and Thickness:

Common Specifications of Gypsum Board:
2400×1200×9.5mm, 2400×1200×12mm, 3000×1200×15mm.

Common Specifications of Calcium Silicate Board:
2440×1220×8mm, 2400×1200×8mm, 2400×1200×10mm, 2400×1200×12mm

Gypsum board and calcium silicate board are commonly used in interior decoration projects for ceiling panels and light steel partition walls.

Gypsum board is soft, easy to process, and highly flexible. It can be cut and bent to create various shapes. Gypsum board is mainly used in residential renovations but is not suitable for humid areas.

Calcium silicate board is hard, with better fire resistance, water resistance, and higher strength compared to gypsum board. It provides better collision protection for partitions, making it less prone to denting or cracking. Calcium silicate board is mainly used in public space renovation projects, such as cinemas, libraries, museums, stations, and other high-traffic areas that require high fire resistance, as well as large underground commercial spaces.

Fire Resistance Rating of Gypsum Board: B1 grade
Fire Resistance Rating of Calcium Silicate Board: A grade