Plaster: Types, Requirements, and Applications in Construction

What Is Plaster?

This id the process of covering rough walls, uneven surfaces in the construction house and other structures with a plastic material, called plaster or mortar. Sometimes, the term ‘rendering’ is used instead of plastering when the plaster or cement is applied to the external surface of the wall either to improve the appearance or to protect then from wether agencies, such as rain heat, etc.

Requirement of Good Plaster

To turn out to be a good plaster, the plastering material must possess to satisfy the following requirement

It should adhere to the background and should remain adhered to during all variations of the climate changes. Also, it should be possible to apply it during all weather conditions.
It should not contract in volume while drying and setting. Otherwise, it will crack and give an unsightly appearance.
It should be cheap and economical.
It should be hard and durable, providing a smooth, non-absorbent, and washable surface with required decorative effect and durability.
It should offer good insulation against sound and high resistance against fire.
It should effectively check the entry or penetration of moisture from the surface.
It should possess good workability.

Types of Plasters

Browning plaster.
Bonding plaster.
Thistle plaster.
Carlite plaster.
Hardwall plaster.
Dri-coat plaster.
One Coat plaster.
Tough coat plaster.

#1. Browning Plaster.

British Gypsum Thistle Browning Plaster undercoat plaster used to provide a smooth, high quality, flat surface to internal walls and ceilings and a durable base for the application of decorative finishes.

#2. Bonding Plaster.

Similar to browning plaster, bonding plaster is also considered as an undercoat on which other things are added. As mentioned earlier, it is an undercoat plaster, which means it is the first coat to be applied to a newly patched wall.

#3. Thistle Plaster.

Thistle plaster products are designed to suit either hand or machine application. Their consistent performance, workability and reliability are assured thanks to our exacting manufacturing standards, which enable plasterers to maximise productivity and cut product wastage on site.

Backed up by a range of compatible, high quality accessories, Thistle plasters produce a high quality surface that’s tough and durable. Thistle plasters meet all customer demands for an aesthetic, low maintenance internal surface finish for a range of standard and specialist applications.

#4. Carlite Plaster.

Carlite plasters provide a smooth high quality surface to internal walls and ceilings. They also provide a durable base for the application of decorative finishes.

The range includes two-coat plastering (using basecoat & finish coat plaster), finish plastering over plasterboards and special application plasters. The plasters can be used in both new buildings and refurbishment and can be applied to all common background types.

Specialist applications include:

X-ray protection
Projection plastering
Airtightness
Salt retarding plastering

Carlite plasters are pre-mixed and only require the addition of clean water. They have a controlled setting time
and are free from inherent shrinkage cracking. All plasters are predominantly supplied in 25kg bags for ease of handling and storage.

Limitations

Carlite plasters should not be used to isolate dampness.
Not suitable for use in continuously damp or humid conditions.

#5. Hardwall Plaster.

Hardwall Plaster is usually applied over cement render or concrete to provide a smooth finish for painting or decoration. It is easy to trowel making initial application and finishing easier. When used with hydrated lime (lime putty), a high gloss finish is produced.

Typical Applications of Hardwall Plaster

1. Hardwall Plaster is typically used in both residential and commercial construction as a finishing coat over cement render or concrete in preparation for painting.
2. When used with hydrated lime (lime putty), a high gloss finish is produced which can be waxed to create a decorative finish.

- In hot or dry conditions it may be necessary to wet the surface before application to prevent the plaster drying out before setting.

#6. Dri Coat Plaster.

Thistle DriCoat is the only plaster recommended for re-plastering walls following damp-proof course treatment.
Heavy salt contamination in the background can cause persistent damp problems.
Conforms to EN 998-1.
This product is certified to BES 6001 achieving a rating of ‘Excellent’
Available in 25kg bags.

#7. One Coat Plaster.

Plastering provides your walls and ceiling with a smooth, durable coating.
One coat plaster is a particular kind of plaster created to offer a simpler approach to plastering.
It allows for application with fewer steps since this plaster acts as base and finishing coat in one.

#8. Tough Coat Plaster.

Thistle Tough Coat is a gypsum undercoat plaster for use on most masonry.
With a final coat of Thistle Multi-Finish, it provides a smooth, inert, high quality surface to internal walls.
It is suitable for application by hand or by plaster projection machine.

Frequently asked questions (FAQs) that could be included in your article about plaster:

What is plaster and why is it used in construction?

Plaster is a material applied to walls and ceilings to create a smooth, durable surface. It’s used to enhance aesthetics, provide protection, and improve insulation against sound and fire.

What are the main requirements of good plaster?

Good plaster should adhere well to surfaces, resist cracking, be cost-effective, durable, provide a smooth finish, offer insulation against sound, be fire-resistant, and prevent moisture penetration.

What are the different types of plaster available?

Types include browning plaster, bonding plaster, Thistle plaster, Carlite plaster, hardwall plaster, Dri-coat plaster, one coat plaster, and tough coat plaster. Each type has specific applications and characteristics.

How do you apply plaster?

Plaster is typically mixed with water to form a workable consistency, then applied using a trowel or plastering machine. It’s spread evenly over the surface, allowed to set, and finished as required.

What are the typical applications of different plaster types?

Browning plaster is used as an undercoat, bonding plaster for initial coats, Thistle plaster for high-quality finishes, Carlite plaster for various applications including X-ray protection, hardwall plaster for smooth finishes over concrete, Dri-coat for damp-proofing, one coat plaster for simplified application, and tough coat plaster as an undercoat for masonry.

What are the considerations for choosing the right plaster for a project?

Factors include the type of surface, environmental conditions, required finish, application method, and specific performance needs such as fire resistance or moisture control.

Can plaster be used on external surfaces?

Yes, rendering is a form of plastering used on external walls to protect against weather and enhance appearance. It involves applying a mixture of plaster or cement to the exterior surface.

What are the advantages of using plaster over other wall finishing materials?

Plaster offers advantages such as durability, ease of repair, fire resistance, and the ability to create smooth, decorative surfaces. It also provides good thermal and sound insulation properties.

How can one ensure the longevity of plastered surfaces?

Proper preparation of surfaces, correct application techniques, using quality materials, and regular maintenance can all contribute to the longevity of plastered surfaces.

Are there any limitations or precautions when using certain types of plaster?

Yes, for example, Carlite plaster should not be used in continuously damp conditions, and precautions such as wetting surfaces may be needed for hardwall plaster in hot or dry climates.