At first glance, a freshly plastered wall looks like the perfect surface for your upcoming painting project. But when it comes to interior painting in San Ramon, painting a newly plastered wall is much more complex than meets the eye.
Before painting over a newly plastered wall, there are crucial factors to consider. Plastering entails applying a smooth layer of compound on walls or ceilings for uniformity, and once cured, it becomes necessary to paint the surface. Painting offers protection while enhancing its appeal, thereby improving the overall aesthetics of the space. Nevertheless, proper selection of quality paint and preparation is essential in ensuring adhesion as well as durability for high-quality results.
When you plan to complete a building project, whether you start a new build or renovate an existing structure, painting over plaster is integral to achieving the desired result. The quality of this process can make all the difference in providing walls that are both visually appealing and able to withstand daily wear and tear. Understanding the proper timing and techniques for painting over plaster is important for the following reasons:
- Proper adhesion
- Surface preparation
- Low moisture content
- Choosing the right paint
- Application techniques
Understanding plaster walls
Plaster serves as a construction material to provide safeguard or ornamentation on walls and ceilings while also being used for fashioning and shaping decorative features. Its production involves heating gypsum, limestone, or other minerals to extract moisture, resulting in a powdered form. When combined with water, it reconstitutes, allowing for molding before solidifying into an enduring surface upon drying.
There are several common types of plaster used in walls, each with specific properties and applications:
- Gypsum plaster is extensively utilized for interior walls and ceilings due to its composition, which chiefly consists of gypsum. The plaster’s smooth finish eliminates the need for applying lime, making it a convenient option. Moreover, Gypsum plaster dries rapidly and has fire-resistant features that make it ideal for modern construction.
- Lime plaster, produced by combining lime with water and sand, has existed for a very long time. Its pliability, permeability, and inherent antiseptic features make it perfect for construction works that preserve history or promote sustainability. Whereas gypsum plaster sets quickly after application, the setting process of lime-based ones typically takes longer.
- Cement plaster is composed of a blend of Portland cement, sand, and water. This type of plaster is highly resistant to moisture, making it ideal for exterior walls and wet areas such as kitchens and bathrooms. Moreover, its durability gives way to strong structural capabilities that can be utilized in various applications, such as on concrete surfaces or over brick and stone.
- Venetian plaster, a decorative finishing plaster that mimics marble or stone, is composed of lime and blended with marble dust. Its application involves adding thin layers, which are subsequently buffed to obtain a glossy finish. Venetian plaster adds an extraordinary hue and texture depth on walls and ceilings when used as embellishment for each specific purpose it serves.
To achieve a strong and long-lasting finish suitable for painting or wallpapering, it is essential to execute the drying and curing process of new plaster carefully. This involves two critical stages – the drying and curing phases, which help harden it. Here’s a detailed overview:
1. Drying phase
- Initial setting – After the plaster is applied to the surface, it begins to set. This is when the plaster starts to harden but is still quite wet. The time it takes for plaster to set varies depending on the type of plaster used, the thickness of the application, and environmental conditions.
- Evaporation – The water in the plaster mixture starts to evaporate, leaving behind the solid materials. Adequate ventilation is crucial during this phase to allow moisture to dissipate, speeding up the drying process. But too much airflow can cause the plaster to dry too quickly, leading to cracks.
- Environmental factors – Temperature and humidity play significant roles in the drying time. Plaster dries best in warm, moderately humid conditions. Cold or overly humid environments slow down the drying process, while hot, dry conditions can cause the plaster to dry too quickly and crack.
2. Curing phase
- Chemical reaction – Curing is the chemical process that continues after the initial drying. During curing, the plaster undergoes a chemical reaction (hydration) that strengthens the bond between the plaster particles, making the surface hard and durable.
- Timeframe – The curing process can take much longer than the initial drying. While plaster may feel dry to the touch in a few days, the curing process can take several weeks to complete. The exact time depends on the type of plaster and environmental conditions.
- Importance of curing – Proper curing is essential for the plaster to achieve its full strength and durability. Premature painting or applying wallpaper can trap moisture, which leads to problems like peeling, bubbling, or mold growth.
Plaster’s drying times are significantly impacted by environmental factors like humidity and temperature. To provide a general understanding, here’s an outline on how these variables can affect the process:
- Humidity – When there is high humidity in the air, plaster takes longer to dry because moist air absorbs water from it at a slower rate. If moisture-saturated air surrounds the plaster surface, its water content doesn’t evaporate as quickly, leading to extended drying times. On the other hand, low atmospheric humidity levels facilitate faster moisture absorption from fresh plaster, accelerating its drying process.
- Temperature – Plaster’s drying time is greatly affected by temperature. Higher temperatures accelerate the evaporation of water from the plaster as heat energy increases its rate. Warm air often contains more moisture than cold air, enabling speedy drying under hot conditions. Conversely, lower temperatures slow down this process and lengthen the time it takes for plaster to dry. Excessively high temperatures may result in rapid dehydration that causes cracking or weakened structure in dried-out plasters.
The risks of painting too soon
What happens if you paint over a plaster that is still wet and has not yet properly dried and cured? When paint is applied too soon, it can lead to several significant problems:
- Paint delamination – One of the typical problems encountered while painting newly plastered walls is paint delamination. Delamination happens when the painted surface becomes detached or peeled away from the wet plaster underneath due to poor adhesion caused by moisture present in it. As time goes on and drying progresses, shrinkage occurs in the plaster, leading to a weakened bond between both surfaces, which finally results in flaking or peeling off actions of paint layers over them.
- Cracking – Drying plaster shrinks and can cause paint to crack if it has already been applied. The unsightly cracks ruin the walls’ aesthetics and expose them to more moisture, exacerbating the issue over time. This phenomenon is known as cracking.
- Mold and mildew growth – When plaster retains moisture for a prolonged duration, it becomes the perfect breeding ground for mold and mildew. Painting over damp plaster can trap moisture, providing an environment that promotes mold growth beneath the surface of the paint. This could result in health complications for inhabitants and cause harm to wall integrity. Mold below painted walls may manifest as staining and considerably impede indoor air quality.
- Adhesion issues – Besides delamination, moisture within damp plaster can hinder proper paint adhesion and result in a feeble bond between the wall and paint. As an outcome, uneven or patchy finishes might emerge where certain areas possess sufficient coverage while others may be thinly coated or produce bubbles.
- Efflorescence – Salts may rise to the surface as moisture percolates through plaster. These salts have the potential to induce efflorescence, a paint surface problem where crystalline deposits form if painted over too soon. This might lead to the paint losing its adhesion to the plaster surface in addition to looking unsightly.
To avoid these problems, ensure that the plaster is completely dried and cured before painting. This typically involves waiting several days or even weeks, depending on how thick the plaster was applied, ambient temperature, and humidity levels.
A painted surface’s overall appearance can be greatly diminished by uneven paint finishes and color irregularities, which can impact the surface’s perceived quality and visual attractiveness. Here are some of the common aesthetic issues that can arise, along with their causes:
Uneven paint finish:
- Brush marks and roller strokes – A finish that has noticeable application strokes may appear amateurish. Using cheap tools, applying too much or too little paint, or forgetting to keep the edge moist while applying paint are common causes of this problem.
- Paint drips and sags – Paint that drips or sags produces uneven surfaces and diminishes the finish’s smoothness. This is usually the result of incorrectly painting on a vertical surface or using excessive paint in one coat.
- “Orange peel” texture – This term refers to a surface with a little uneven texture resembling orange skin. It occurs frequently while spray painting and can be caused by a few things, such as applying too thickly, using too viscous paint, or misting at the wrong distance from the surface.
- Lap marks – Occurring edges of partially dried paint that give the paint a visible variation in appearance. Overlapping wet and drying paint results in lap markings caused by the painter failing to maintain a wet edge.
- Mismatched colors – Even tiny differences in paint tone can be seen and take away from the painted surface’s homogeneity. This can occur when paint is applied improperly or not well mixed before application.
- Fading and chalking – Paint can fade or start to chalk over time due to exposure to sunlight and environmental factors, resulting in uneven surface colors. The rate at which this happens can be influenced by the pigments and paint quality.
- Bleeding – Color discrepancies may result from bleeding—older colors or stains seeping through the fresh paint coat. This is frequently the result of improper priming when necessary or insufficient surface preparation.
- Patchiness – An uneven paint application can result in a patchy look, particularly on porous surfaces. Applying the appropriate primer and properly preparing the surface will usually remedy this.
One cannot stress enough how crucial it is to have a well-ventilated area for plaster drying because it directly affects the strength, longevity, and safety of the plastering job. Here are a few main justifications for why ventilation is essential:
- Moisture control – To avoid cracking, plaster must dry gradually and uniformly. Plaster that dries too rapidly or unevenly can cause structural flaws; a well-ventilated area allows excess moisture to escape and lowers that danger.
- Mold and mildew prevention – Sufficient ventilation aids in preventing moisture accumulation, which can foster the growth of mold and mildew. These can endanger residents’ health in addition to causing harm to the plaster.
- Strength and durability – The plaster’s strength and durability are improved by proper drying. Plaster may stay internally damp in the absence of adequate ventilation, even though the surface seems dry. This can result in long-term problems like crumbling or improper adhesion to surfaces.
- Air quality – VOCs and other pollutants may be released into the atmosphere during drying. Proper ventilation guarantees their dispersion, preserving superior air quality and mitigating any health hazards for those in proximity.
- Economy and efficiency – Well-ventilated areas can speed up the building or remodeling process by cutting down on the drying time of plaster. This may result in lower project costs and less disruption.
Speeding up the drying process of various items or substances safely involves techniques that minimize risk while effectively reducing moisture. Here are some general tips for various scenarios:
- Use direct sunshine to hasten drying when suitable, but exercise caution when handling materials that may fade or deteriorate when exposed to UV radiation.
- Use absorbent materials like sponges, towels, or specialty items to absorb moisture.
- Dehumidifiers can be used to lower the total humidity in indoor spaces, which can hasten the drying process for many kinds of materials.
- To enhance evaporation, position a fan to blow air over the surface; however, stay away from excessive speeds that could cause dust to adhere to the surface.
- Paint in sparse layers. One thick coating takes longer to dry than several tiny layers.
- Use a dehumidifier to reduce humidity in the room and speed up drying.
- When possible, increase the room temperature to speed up drying.
Primer: your best friend
Using a primer on new plaster walls is crucial for several reasons:
- It seals the surface.
- It improves the adhesion of the finishing paint.
- It provides the paint finish with a uniform appearance
- It conceals stains.
- It enhances paint performance and durability.
- It provides a barrier against moisture.
Selecting the right type of primer is crucial for a long-lasting and attractive surface when preparing plaster walls for painting or wallpapering. Important elements to consider include the condition of the walls, the kind of paint you want to use, and any problems (such as stains or smells) that need to be fixed.
The following primer types are good for plaster walls, along with some advantages of each:
- Polyvinyl acetate (PVA) primer – This type of primer is made especially for plaster wall sealing. It results in a more consistent finish by keeping the plaster from absorbing too much paint. Additionally, PVA primer helps the paint adhere to the surface, requiring less paint and ensuring a longer-lasting finish.
- Oil-based primer – If the plaster walls are old and have never been painted, oil-based primers work wonders for sealing and protecting them. Their ability to stop stains and bleed-through from the underlying material is especially strong. Additionally, oil-based primers stick to the surface well, giving any kind of paint a strong foundation.
- Shellac-based primer – Primers made of shellac have excellent stain-blocking qualities, which makes them perfect for plaster walls that have come into contact with stains, water, or smoke. They form a firm surface that is perfect for painting and dry quickly. Odors can also be effectively sealed with this kind of primer.
- Latex primer – Compared to oil-based primers, latex primers are water-based and less odorous, making them easier to use and clean up after. They are flexible, which helps to reduce cracking, and they adhere well to plaster surfaces. Paint can be smoothly applied, and porous surfaces can be sealed with latex primers.
- Acrylic primer – Another water-based primer with good adhesion and durability is the acrylic primer. It performs well under a range of paint types and is appropriate for freshly painted or previously painted plaster walls. Acrylic primers can aid in moisture resistance and have a lower tendency to discolor over time.
- Stain-blocking primer – A stain-blocking primer is ideal for surfaces with problematic stains or discoloration. This type of primer is designed to prevent stains from bleeding through the finishing paint, ensuring a clean and uniform appearance. It can be either oil-based or water-based, depending on the specific formulation.
Applying primer to plaster walls before painting is essential to ensure a smooth, durable finish. Here’s a step-by-step guide on how to apply primer correctly:
1. Prepare the walls
- Clean the walls – Remove any dust, dirt, or grease from the walls. You can use a damp sponge or cloth and a mild detergent if necessary. Let the walls dry completely.
- Repair damages – Fill any holes or cracks with plaster or a suitable filler. Once the filler has completely dried, sand the repaired areas until smooth.
- Sand the walls –Lightly sand the entire wall surface with fine-grit sandpaper to ensure the primer adheres well. This step is especially important if the plaster is glossy or has been painted previously.
- Remove dust – Remove dust with a clean, damp tack cloth after sanding.
2. Apply primer
- Choose the right primer – Use a primer that is suitable for plaster walls. If the walls are new and have never been painted, a plaster sealer or a primer sealer is recommended to prevent the plaster from absorbing too much paint.
- Tape off areas – Use painter’s tape to protect any areas you don’t want to be primed or painted, like trim, windows, and doors.
- Cut in – Start by “cutting in” the primer around the edges of the wall with a paintbrush. This means painting a 2- to 3-inch strip along the edges, corners, and any areas where a roller can’t reach.
- Use a roller for large areas – For the main surface of the wall, use a roller. Dip the roller into the primer, removing any excess to avoid drips. Apply the primer using slightly overlapping strokes, starting from the top of the wall and working your way down.
- Apply evenly – Ensure an even application of primer across the wall. Avoid applying too much primer in one area and not enough in another.
- Allow it to dry – Let the primer dry completely. Check the primer’s instructions for drying times, as it may vary depending on the brand and type.
3. Inspect and apply a second coat if needed
- Inspect the coverage – Once the primer is dry, check for any uneven areas or spots where the plaster shows through.
- Apply a second coat if necessary – If the coverage is uneven or insufficient, apply a second coat of primer, following the same steps as before.
Choosing the right paint and tools
Here’s a rundown of the best types of paint for plaster walls, focusing on breathability and overall performance:
- Lime-based paints – Lime-based paints are a great option for both new and old plaster walls due to their high breathability and inherent antimicrobial properties. They complement the inherent qualities of plaster nicely, enabling moisture to escape the surface, which is especially helpful in older homes where moisture problems are more common.
- Clay paints – Clay paints have a distinctive look, a natural, matte texture, and great environmental benefits. They can help control indoor humidity levels because they are very breathable, releasing moisture when the air is dry and absorbing it when the air is damp. They are perfect for plastered walls and promote indoor air quality.
- Silicate (mineral) paints – These paints penetrate the plaster’s surface and form a chemical bond with it, producing a long-lasting and extremely breathable layer. They are resistant to algae, mold, and UV rays. Plaster walls, whether interior or exterior, work well with these paints.
- Distemper paint – Distemper is a type of paint traditionally made from water, chalk, and pigment. Lime is sometimes used as a binding agent. It’s very breathable and gives off a soft, velvety finish. However, it’s not as durable as modern paints and is prone to marks and scuffs, so it’s best for low-traffic areas and ceilings.
Having the right tools and equipment is crucial to achieving a smooth application in your painting projects. Below is a rundown of recommended items for house painting:
- Paint rollers and covers
- High-quality brushes
- Painter’s tape
- Sandpaper or sanding blocks
- Paint tray and liners
- Extension pole for paint roller
- Drop cloths
Painting new plastered walls: step-by-step guide
After ensuring the plaster has dried and primed the newly plastered walls, now it’s time to paint them! Following this step-by-step guide below should help you achieve a professional-looking finish on your newly plastered walls. Take your time with each step to ensure the best possible outcome.
1. Apply the top coat:
- Paint choice – Use a water-based emulsion for the final coat. You may need two or more coats to achieve the desired finish and opacity.
- Technique – Apply each coat with a roller in a uniform direction, using a brush for edges and corners. Allow each coat to dry completely before applying the next. Drying times can vary based on paint type and environmental conditions.
2. Do the finishing touches:
Inspect the walls for any missed spots or uneven areas after the final coat has dried. Then, use a small brush for any necessary touch-ups.
- Keep the room well-ventilated during the painting process to aid in drying and to reduce paint fumes.
- Good lighting is important to spot any painting imperfections.
Aftercare and maintenance
Maintaining your paint job’s lifespan and aesthetic appeal requires proper maintenance for freshly painted plaster walls. The following tips will help you maintain your freshly painted plaster walls in excellent condition for years to come:
- Allow proper drying time – Give your freshly painted plaster walls enough time to dry completely. The paint normally takes two to four weeks to cure entirely, though this can change depending on the paint kind and the surrounding circumstances. To avoid damaging the walls during this time, refrain from touching or cleaning them.
- Avoid humidity – Steer clear of high humidity as it can negatively impact paint drying and curing. To ensure that the paint cures properly, try to keep the room at a reasonable temperature and with good ventilation.
- Clean gently – Gently clean the walls, if necessary, after the paint has completely dried. Dust or grime can be gently removed using a soft, moist cloth. Abrasive cleansers and harsh chemicals should not be used on painted surfaces since they might cause damage.
- Address spills immediately – To avoid staining the wall, clear up spills as soon as you can. Instead of rubbing, which could smear the spill or harm the paint, gently blot the spill with a moist cloth.
- Touch up as needed – To keep the walls looking new, touch up any chips or scratches using leftover paint. Try to blend the touched-up area with the surrounding wall using a little brush for accuracy.
- Protect from furniture and sunlight – Keep furniture and other items a reasonably short distance away from the walls to avoid scuffs and scratches. Protect the paint from direct sunshine. Furthermore, painted surfaces will eventually fade from continuous exposure to direct sunshine, so to prevent UV damage to your walls, think about installing window treatments.
- Use the right paint for repainting – If you ever decide to repaint the walls, be sure to select a paint that works well with the current finish. Prepare the surface thoroughly before painting it with new paint for optimal results.
- Dust regularly – Regular dusting can prevent the buildup of dust that might stick more firmly to the walls over time. Use a soft, dry cloth or duster to remove surface dust gently.
During the first few weeks or months after painting new plaster walls, there are a few frequent problems to be aware of. If not appropriately addressed, they may have an impact on the paint job’s longevity and appearance:
- Drying and curing time – Depending on the thickness and environmental conditions, the plaster must completely dry before painting, which may take several weeks. Painting on wet plaster may cause paint blistering, peeling, or discoloration.
- Efflorescence – Efflorescence is a condition in which the plaster dries and salt deposits accumulate on its surface, leaving behind a white, powdery residue. It may flake off paint if it is painted over. It is essential to remove efflorescence before painting.
- Cracking and shrinkage – Fresh plaster may develop cracks and shrink as it dries. These should be filled and smoothed over to guarantee a smooth surface before painting.
- Poor adhesion – Smooth, unprimed plaster may not allow the paint to stick well. Use a primer made especially for fresh plaster to enhance paint adhesion for a more permanent finish.
- Moisture damage – Paint may bubble or peel if there is considerable humidity or if the underlying plaster is still damp. These problems can be avoided by making sure the plaster is entirely dry and has adequate ventilation.
- Mismatched absorption – An uneven finish may result from disparities in the absorption rates of the original plaster and patched regions. Making the absorption rates uniform on the wall can be achieved by applying a first coat of paint that has been diluted, known as a mist coat.
- Mold and mildew – Painted plaster walls are susceptible to the growth of mold and mildew in high-humidity locations like bathrooms and kitchens. This can be avoided using mold-resistant paint or mixing a mold inhibitor into your paint.
- Color inconsistency – Variations in texture or inconsistent drying times for plaster might result in observable color differences after painting. A consistent color can be achieved by applying a high-quality primer or adding an extra layer of paint.
Proper preparation of the plaster walls before painting is key to avoiding these. This includes ensuring the plaster is completely dry, applying a suitable primer, using the correct type of paint, and addressing any surface imperfections. Regular checks in the months following painting can also help catch and correct any emerging problems early.
When to call a professional
Hiring a professional painting contractor to paint freshly plastered walls can be beneficial in several ways, avoiding potential issues and ensuring the best results. Here are some situations where hiring a professional painting contractor might be the better choice:
- High-quality finish
- Ability to deal with complex surfaces or designs on walls
- Speed and efficiency
- Knowledge of materials
- Ability to deal with problematic walls (such as bumps from an improperly plastered surface)
- Warranty and insurance
- Stress reduction
- Value for money
Initially, hiring the best painters in the Bay Area is costlier than choosing the DIY route. However, the benefits of hiring a professional painter often outweigh the cost, ensuring a stress-free process with excellent and long-lasting results. This saves you money and stress in the long run.
Choosing a reputable painting contractor involves several steps to ensure you get quality service, value for your money, and a satisfying outcome for your painting project. Here’s a guide to help you through the process:
- Research and get referrals – Start by asking friends, family, neighbors, or colleagues for recommendations. You can also search online for painting contractors in your area and read reviews on platforms like Google, Yelp, or Angi (formerly Angie’s List).
- Check credentials – Look for painting contractors who are licensed, bonded, and insured. These credentials ensure that the contractor is legitimate and can compensate for any damage or injury during the project.
- Experience and expertise – Consider the experience and expertise of the painting contractor. Ask how long they have been in business. Do they specialize in either residential or commercial painting? Look for painting contractors who have experience working on projects similar to yours.
- Portfolio and references – Ask the painting contractor for a portfolio of their past work. This will give you an idea of the quality of their workmanship and the projects they have completed. Additionally, ask for references for past clients and follow up with them to ask about their experience working with the contractor.
- Get multiple quotes – It is best to get quotes from at least three different painting contractors. Ensure the quotes are detailed and include the cost of labor, materials, paint, and other expenses. Compare the quotes you received to determine which contractor offers the best value for your money.
- Ask about process and materials – Inquire about the painting process and the materials the contractor intends to use for your project. A professional contractor should easily explain their process in detail and recommend high-quality paints and materials that will produce long-lasting results.
- Communication and professionalism – Pay attention to the contractor’s communication and professionalism throughout the initial inquiry process. A reliable contractor should be responsive to your inquiries, provide clear and detailed information, and be punctual for appointments.
- Contracts and warranties – Once you’ve chosen a painting contractor, make sure to get a written contract. It should include the scope of work, project timeline, payment schedule, and any warranties or guarantees offered. Review the contract carefully before you sign it, and clarify any terms or conditions you don’t understand.
- Trust your instincts – Ultimately, your instincts are important when choosing a painting contractor. If something doesn’t feel right or if you have doubts about a particular contractor, it’s better to continue your search until you find a contractor with whom you can feel comfortable and confident working.
By following these steps, you can select a professional painting contractor who will deliver high-quality results and ensure a successful painting project.
Is it advisable to paint on freshly plastered walls? The answer is yes! But as this differs from painting regular drywall, there are a few things you should think about beforehand. Painting newly plastered walls is a labor-intensive procedure that calls for some perseverance and meticulous attention to detail. You risk having a less-than-ideal finish if you don’t handle this task correctly.
It requires more time and attention to paint walls with freshly laid plaster. Therefore, hurrying the painting process can result in several issues that you could have to deal with again.
If you don’t want these scenarios to happen, it is best to hire a professional house painting contractor in Pleasant Hill, CA, to paint newly plastered walls in your home. Give Custom Painting, Inc. a call or message! Call 925-294-8062 or message here today to request a free estimate.