What Are The Limitations of Plaster?

Limitations of Plaster in Auckland’s Unique Conditions

Understanding the Basics of Plaster

Plaster has long been a popular choice for exterior finishes, especially in Auckland. It offers a sleek, polished look and can be used on a variety of surfaces. But, like any material, plaster has its set of limitations that you should be aware of, especially if you’re considering it for your renovation project.

The Moisture Challenge

One of the primary issues with plaster, especially in the humid Auckland climate, is its susceptibility to moisture. If not properly sealed and maintained, moisture can seep into plaster, leading to problems like:

• Bubbling or blistering of the paint over the plaster
• Development of mould or mildew
• Weakening and eventual crumbling of the plaster

Drying Time and Climate Influence

Auckland’s diverse climate, especially in suburbs like Greenhithe, can influence plaster’s drying time. The temperature and humidity play significant roles:

• Too cold, and the plaster might not set properly.
• Too humid, and it can take longer to dry, leaving it vulnerable to contaminants.

Structural Movement Complications

Plaster doesn’t cope well with structural movements. Over time, homes, especially in areas like Torbay, can shift due to various reasons including soil changes or seismic activity. Such movements can lead to:

• Cracking of the plaster
• Chipping at the edges

Maintenance and Durability

While plaster provides a sleek finish, it requires regular maintenance to keep it looking fresh. Factors to consider include:

• Regular sealing to prevent moisture infiltration
• Painting with appropriate paint types to ensure longevity
• Immediate repair of minor cracks or damages to prevent extensive damage

Auckland Council Bylaws

For those considering exterior plastering, it’s essential to be aware of Auckland Council’s regulations. Certain bylaws can influence the type of plaster you can use or the methods of application. Always consult with your local council, especially if residing in areas with specific codes or historical significance.

Tools and Materials for Gib

Understanding Gib Plastering

Gib plastering is an intricate process that demands precision, patience, and the right set of tools and materials. Whether it’s for an elegant interior finish in a Devonport villa or achieving smooth walls in a contemporary Pukekohe home, ensuring you have the right equipment is essential.

Plastering Trowels

• Finishing Trowels: These have a smooth and flat blade, ideal for achieving a polished finish on the plaster.
• Bucket Trowels: A square-shaped trowel perfect for scooping plaster out of the mixing bucket.
• Corner Trowels: Specifically designed for perfecting the corners, ensuring a smooth and even finish.

Hawks An indispensable tool for plasterers, a hawk is a flat board with a handle beneath. It’s used to hold a portion of plaster mix, making it easy for the plasterer to access and apply the plaster using a trowel.

Floats Floats help in achieving the final smooth finish. They are used to smooth out any trowel marks and to compact the plaster, improving its durability.

• Polyurethane Floats: Lightweight and perfect for giving a smooth finish.
• Sponge Floats: Often used on the final coat, they can create a smoother finish by bringing the fine particles of the plaster to the surface.

Mixing Equipment

• Mixing Buckets: These should be large and durable to handle the weight and quantity of the plaster mix.
• Drills with Paddle Mixers: Essential for mixing the plaster to the right consistency. The paddle attachment ensures that the mix is even and lump-free.

Straight Edges and Feather Edges Used to ensure walls and surfaces are perfectly flat. They help in identifying low spots on the surface that might need more plaster.

Mesh and Jointing Tape

• Mesh: Fibreglass mesh provides added strength, especially around problematic areas that might be prone to cracking.
• Jointing Tape: Essential for seams between gib boards. It helps to prevent cracks along the joints.

Gib Stopping Compounds

These are pre-mixed or in powder form. They are used to fill and finish the seams between the gib boards, ensuring a smooth and seamless appearance.

Sanding Tools Once the plaster has dried, it may require sanding to achieve a super smooth finish.

• Hand Sanders: Good for smaller areas or touch-ups.
• Pole Sanders: Allow for an extended reach, perfect for ceilings or high walls.

Safety Gear Given the nature of the job, and especially considering Auckland’s varied weather conditions from Glen Eden’s occasional rains to Devonport’s sea sprays, ensuring safety is paramount.

• Safety Glasses: To protect eyes from any splashes.
• Dust Masks: Essential when sanding down dried plaster.
• Gloves: To protect hands from the alkaline pH of wet plaster.

Weighing the Plaster Options

There are several plaster types, each with its own set of advantages and limitations. Here’s a quick table to help you navigate:

The Bottom Line

While plaster offers a range of benefits, its limitations, especially in Auckland’s unique climate, highlight the importance of engaging a professional. Exterior plastering contractors or solid plasterers possess the expertise and knowledge to navigate these challenges, ensuring your home renovation stands the test of time. If you’re in the Auckland region, it’s wise to consult with a specialist to get the best results.

Key Takeaways: Understanding Plaster’s Limitations

Susceptibility to Moisture Plaster can absorb moisture, making it less ideal for areas with high humidity or potential water exposure, like bathrooms without adequate ventilation.

Cracking Over Time With age and exposure to varying temperatures, plaster can develop cracks, especially if not applied correctly.

Weight Concerns Plaster is heavier than other wall finishes. This means additional support may be required, especially for ceilings.

Longer Drying Time Compared to other materials, plaster takes longer to dry, delaying the completion of a project.

Limited Flexibility Unlike drywall, plaster isn’t flexible, making it more susceptible to damage from direct impacts or structural shifts.

Higher Costs Plastering can be more expensive than other wall treatments, both in terms of materials and labour.

Skill-Intensive Application Applying plaster requires a high skill level, which can make DIY attempts challenging and less durable.

Difficulty in Alterations Once set, making alterations or installations (like adding electrical outlets) can be more challenging with plastered walls.

Potential for Dust Sanding plaster can produce a lot of dust, making it imperative to seal off the work area and wear appropriate safety gear.

Thermal Insulation Limitations Plaster doesn’t offer as much thermal insulation as some modern materials, potentially impacting energy efficiency.

Acoustic Limitations While plaster can provide some soundproofing, there are other materials specifically designed for better acoustic insulation.

Specialised Repairs Damages to plastered walls often require specialised repair techniques and materials, potentially leading to higher repair costs.

Decoration Restrictions Certain adhesives or heavy wall hangings may not adhere well to or could damage plaster walls.

Surface Preparation Requirements Before plaster application, the surface requires thorough preparation to ensure proper adhesion and a smooth finish.

Limited Resistance to Sharp Impacts Sharp objects can easily gouge or dent plaster surfaces, especially if the plaster is not mixed or applied correctly.

Understanding Plaster Limitations: Frequently Asked Questions

Is plaster suitable for high-humidity areas?

No, plaster can absorb moisture, making it less suitable for areas with high humidity or potential water exposure, such as certain bathrooms.

Why is my plaster wall cracking?

Plaster can develop cracks over time due to age, exposure to varying temperatures, or if not applied correctly.

Can I use plaster for ceilings without additional support?

Plaster is heavier than other wall finishes, so additional support may be required, especially for ceilings.

How long does plaster take to dry?

Plaster generally takes longer to dry compared to other materials, the exact time can vary based on the type and conditions.

Is plaster more expensive than drywall?

Yes, plastering can be more costly than drywall in terms of both materials and labour.

Can I apply plaster myself?

Plastering requires a high skill level, so while DIY is possible, it’s recommended to hire professionals for a durable finish.

How do I make alterations to a plastered wall?

Making alterations, such as adding electrical outlets, can be more challenging with plaster. Special tools and techniques are often needed.

Does plaster offer good insulation properties?

Plaster doesn’t provide as much thermal insulation as some other materials, which can affect a home’s energy efficiency.

Can I hang heavy items on a plaster wall?

Heavy wall hangings might not adhere well to plaster and could cause damage. It’s important to use the right anchors and fixtures.

How can I repair damaged plaster?

Damaged plaster often requires specialised techniques and materials for repair. It’s advisable to consult or hire a professional for significant damages.