Sometimes, special materials are needed in plastering or over the plastered surfaces. It happens when specific needs are to be met, such as increased durability, better or attractive appearance, fire-proofing, sound and heat insulation, etc. The names given below may not be common for the common men, hence one must be careful with remembering them.
- Acoustic Plaster
- Asbestos Marble Plaster
- Barium Plaster
- Granite Silicon Plaster
- Gypsum Plaster (Plaster of Paris)
- Kenee’s Cement Plaster
- Martin’s Cement Plaster
- Parian Cement Plaster
- Scagliola Plaster
- Sirapite Plaster
- Snowcrete and colourcrete cements
- Thistle Hardwall
Let’s discuss the top five, in few more details.
1. Acoustic Plaster
As the name suggests, this plaster is helpful in sound insulations as needed in auditoriums, theatres, and halls, etc. It is applied in two coats, 6 mm each, with a wooden float. The special material used is a gypsum mixture applied as the final coat. In other words, the gypsum mixture is used for the surface finishing.
how does Acoustic Plaster work?
The material used in acoustic plaster undergoes a chemical reaction forming tiny gas bubbles. These gas bubbles while coming out create small openings in the coat. These honey-combed minute holes/openings absorb the sound and thus provide the acoustic insulation, and thus the sound does not leave the room/hall as much it would have been without the special plaster.
2. Asbestos Marble Plaster
This plaster is used for giving a marble-like finish. It contains cement, Asbestos, and finely crushed marble.
3. Barium Plaster
This plaster is used mostly for safety purposes in X-ray rooms. The materials used are cement, Barium Sulphate, and sand.
4. Granite Silicon Plaster
This is a bit costly as a material for plastering, but its properties such as quick setting, and resistance against cracking compensate for the high price.
5. Gypsum Plaster (Plaster of Paris)
Gypsum has a fast setting property, sets within 3 minutes when mixed with water. Other useful properties it has are fire resistance, lightweight and low cost. Let’s discuss this in detail.
- Gypsum can be used on timber and metals, to make them fire-resistant.
- It has acoustic insulation property.
- It has light weight.
- Gypsum plaster is useful in ornamental works.
- It has good adhesion to fibrous materials.
- It sets with little change in volume, hence shrinkage and cracks or not easily formed.
Precaution:
Gypsum is soluble in water, hence it should not be used for external uses, where rainwater may have its reach. For indoor works, it is perfect.
6. Kenee’s Cement Plaster
Kenee’s cement is obtained by calcinating Gypsum with alum. It sets to a very hard state within few days and takes out a glass-like white polish finish. It is used for angles, skirtings, etc. Because of its appealing finish, it is used in ornamental works and decorative plastering.
7. Martin’s Cement Plaster
Martin’s cement is obtained when pearl ash is calcined with Gypsum (also known as Plaster of Paris.) It has fast-setting properties, just like Gypsum, and it is useful for internal works.
8. Parian Cement Plaster
Borax calcined with Plaster of Paris forms Parin Cement Plaster. It is cheaper than Kenee’s cement due to the low cost of Borax than alum. It is used in interior works only.
9. Scagliola Plaster
When Kenee’s Cement is dissolved in coloring pigments and glue, Scagliola Plaster gets formed. It is used for plastering pillars, pilasters, and panels, etc. It looks like marble when dried.
10. Sirapite Plaster
When Plaster of Paris (POP) is slaked in petroleum, Sirapite Plaster is obtained. A white hard surface is obtained once it is dried. It is a quick setting type of plaster, due to gypsum as the basic material. It is fire resistant too.
11. Snowcrete and Colorcrete Cements
Given the white color of white cement, it is given a trade-name of snowcrete. Similarly, a colored cement is named colourcrete. They are used mostly for the good appearance of the walls.
12. Thistle Hardwall
High-grade POP (gypsum) is used to create a plastering material called ‘thistle hardwall’. It is used for internal works and excellent finish.
