Hello! Welcome to the next blog post. Today we will discuss in detail how to stop plaster from cracking when drying the surface. If you are also experiencing this type of frustration issue in the building, this is the right place to avoid plaster cracks.
This is a very frustrating building problem after applying plaster to the building wall. Do you know what the reason is? please comment. If you are not able to stop plaster from cracking when drying the plaster. We will focus on this topic today.
The basic reasons for plaster cracking after the wall is plastered are the poor quality of the materials, the application process, and low-experienced manpower. The main part of the problem is manpower, experience, and knowledge. Let’s discuss this in detail :
What are the types of plaster surface cracks?
First of all, we will explain the types of plaster cracks because we should know what a type of crack is and how to stop plaster from cracking when drying for such a type of plaster crack. Following are the major types of cracks that occur in the plaster wall of the building:
These are very thin cracks in the plaster. These are superficial cracks that occur with minor settling and temperature variation. Normally, this type of crack occurs in the plaster. They are usually not a cause for concern and can be easily repaired.
These can be caused by the normal settling of a building. This type of crack also indicates more serious structural issues. They might result from uneven foundation settling or stress on the wall due to load-bearing elements.
Horizontal cracks are more serious because they might signal major strain or stress on the wall, which could be caused by soil expansion, pressure from water, or other structural issues. These cracks should be investigated and fixed as soon as possible.
Diagonal cracks may indicate that the structure is falling unevenly. They may also be caused by structural movement, changes in soil conditions, or poor engineering procedures.
These cracks resemble a set of stairs and are often seen in brick walls. They can indicate movement in the foundation or the shifting of load-bearing components.
L-shaped cracks are typically found at corners or intersections of walls. They can occur due to the differential movement between two intersecting walls.
These are interconnected cracks that resemble a map. They are generally indicative of a more serious underlying issue, such as excessive structural movement or inadequate support.
Cracks Around Openings
Cracks around doors, windows, and other openings can occur due to the settling of the building or poor installation practices. They might also suggest issues with the lintels or headers supporting the openings.
Expansion Joint Cracks
These cracks occur at predetermined joints or seams in large structures to accommodate expansion and contraction. They are intentional and help prevent random cracks elsewhere.
Crazing cracks are fine, network-like patterns on the surface of plaster, often resembling shattered glass. They are typically due to the drying process and are common in new plaster.
If you notice cracks that are progressively getting wider, it’s a sign that there’s ongoing movement or settling that needs immediate attention.
How to I stop plaster from cracking when drying?
This is very challenging when you select quality construction materials and construction manpower. Generally, if you did plaster work in the wall, then for some reason plaster cracks are visible. Do you know what the reason is for the plaster crack? How do you stop plaster cracks when you dry the plaster surface? If you know, please suggest it to us.
Now we will discuss basic terms and tips to stop plaster from cracking when drying. I have mentioned possible reasons and avoided such types of problems at the construction site. What can we do at the site to stop plaster from cracking when drying the plaster surface? Discuss in detail:
Selection of Quality construction materials
The first thing we should do is select the best type of construction materials. Such as cement, sand, and chemicals. It should be verified by the LAB. such as the Grade of cement and sand, and the manufacture date of materials. So the selection of materials is the major factor in plaster cracks. If you stop plaster from cracking when drying the surface, then select quality construction materials.
Follow the standard guideline
Standard building codes should be followed properly to stop plaster cracking when drying the surface. This is also a major factor to occurs these issues in buildings. If you properly follow the latest building code when the construction automatic avoid plaster cracking issues.
Preparation of wall surface
This is the second phase to avoid plaster cracks. It should be a net and clean surface before applying plaster on the wall. The following tips should be followed before wall plastering:
Remove any dirt, dust, grease, or loose particles from the wall surface before. Use a broom, brush, or vacuum cleaner to clean thoroughly. The standard size of brick should be used for smooth wall surfaces to minimize surface preparation work.
Fill up any cracks holes and dents in the wall using suitable filler materials or patching compound. Then dry the filler compound and sand it down to create a level of surface.
If there is any loose paint or wallpaper, remove it carefully. Sand the surface lightly to create an even texture.
If the wall has uneven areas, use a plaster remover or a putty knife to smooth the surface. This will help create an even plaster application.
Depending on the condition of the wall, you Should apply a primer or sealer. This is very important if the wall is porous or has a variety of surfaces. The sealer will help the plaster attach better.
Before applying the plaster, wet the wall surface with water using a spray bottle. This prevents the plaster from drying too quickly and increases its better adhesion. So these are the surface preparation of the wall before applying plaster.
Use bonding agent
This is the third step to applying plaster on the wall. You can use a bonding agent to properly attach plaster to the wall. If you need a very smooth or non-porous surface, applying a bonding agent can enhance the plaster attached.
Follow the manufacturer’s instructions for the application of plaster. A resinous emulsion, super latex, Latex LW+, and an acrylic liquid can be used as bonding agents. These chemicals also help to waterproof surfaces.
The following chemicals can be used in the proper ratio. The bonding agent can play a major role to stopping plaster from cracking when drying the plaster surface.
Cover any surfaces adjacent to the area you are plastering with painter’s tape or plastic sheeting to protect them from the plaster.
It should maintain a bonding chemical and cement ratio is 1 liter: 5 bags.
Proper Mixing ratio
Cement, sand, chemicals, and water should be mixed in the proper mix design for plaster. Each and every mix ratio should be maintained.
So these are the major factors to avoid plaster cracks. Have you properly followed the mix design on the packaging manual? Hope you followed on the construction site.
Follow the instructions on the plaster packaging to mix it with water to the correct ratio. Use the mixing paddle attached to the drill for efficient mixing.
The proper mixing ratio for plaster is a 1:3 to 1:5 cement-sand ratio. Proper mixing ratio helps to stop plaster from cracking when drying.
The procedure for applying plaster
Begin applying the plaster using a trowel or a hoe and trowel combination. Begin at the top and work your way down. Use sweeping motions to spread the plaster evenly. First, apply a thin base coat (scratch coat), and once it has been partially set, apply a second coat (finish coat) for a smooth surface.
Use a trowel to smooth and level the plaster surface. Keep the trowel slightly damp to prevent sticking. Feather the edges of the plaster to blend seamlessly with the surrounding wall.
If you want a textured finish, use a texture roller, brush, or other tools to create the desired pattern before the plaster has completely set.
Thickness of plaster
It should be maintained that the thickness of the plaster is 6 mm to 12 mm at the inner surface and 18 mm to 22 mm at the external surface. It is necessary to stop plaster from cracking when drying the surface.
|Application||Standard Plaster Thickness (mm)|
|Interior Walls and Ceilings||10 – 15|
|Exterior Walls||20 – 25|
|Skim Coat (Final Layer)||2 – 3|
|Render Coat (Base Layer)||12 – 18|
|Plaster Over Brickwork||20 – 25|
|Plaster Over Concrete Block||15 – 20|
|Plaster Over Metal Lath||15 – 20|
|Plaster Over Drywall||6 – 10|
|Plaster Over Wood Lath||10 – 15|
After completion of the plasterwork (scratch coat and finished coat), proper curing is necessary for the hydration of cement.
If you are cured properly on the finishing surface, the cement can function properly. So curing is one of the major factors in stopping plaster from cracking when drying. After proper curing, the plaster surface can function well.
Follow the manufacturer’s recommendations for plaster curing. During the curing process, keep the area slightly moist to prevent cracking. Curing varies according to the location of the site.
It should be necessary for a plaster to cure for 7 to 10 days to get better strength. This is also a major factor in stop plaster from cracking when drying.
I hope you understand this topic How do I stop plaster from cracking when drying? Basically, the selection of quality materials, surface preparation, the ratio of mixing, adding bonding chemicals, using experienced manpower, and surface curing are major factors in avoiding plaster cracking when drying the surface. When treating cracks, you must first understand the different types of plaster cracks. If you have any queries related to this topic, please fill out the contact page.
Why does plaster crack while drying?
Plaster cracks during drying due to shrinkage as moisture evaporates. Factors like improper mix, application thickness, and inadequate curing can contribute to cracking.
How can I minimize plaster cracking?
Can I use additives to prevent cracking?
Yes, some additives enhance plaster’s workability and reduce cracking. Consult with experts to choose suitable additives and follow manufacturer recommendations.
How long should I wait before painting the plaster?
Allow the plaster to dry completely and cure for at least a week before painting. Check the manufacturer’s guidelines for specific drying times.
What if I discover cracks after drying?
For small cracks, use a plaster filler or joint compound. For larger cracks, consult a professional to assess and address underlying issues before repairing them.
Can humidity affect plaster drying?
Yes, high humidity can slow drying and increase the risk of cracking. Control humidity levels in the drying environment for consistent and gradual drying.
Is reinforcing mesh necessary to prevent cracking?
Reinforcing mesh, like fiberglass mesh, can help distribute stress and minimize cracking. Use it in high-stress areas or when plastering over uneven surfaces.
Can I speed up plaster drying to save time?
Rapid drying, such as using excessive heat, can lead to more cracking. It’s best to allow the plaster to dry gradually for optimal results.
Should I consult a professional for plastering?
If unsure about plastering techniques, it’s advisable to consult a professional plasterer to ensure proper application and minimize the risk of cracking.
Can I repair the cracked plaster myself?
Small cracks can often be repaired with DIY methods, but extensive or recurring cracking may indicate deeper issues. In such cases, consulting a professional is recommended.