Why Is My Paint Sagging? (Drips and Runs)

If you’ve ever painted a wall, you know how satisfying it can be. Unfortunately, not all paint jobs have happy endings. Sometimes your paint will start to sag or drip down the wall. This phenomenon is known as “paint sagging.” So, what exactly causes it?

The main reason paint sags is that you applied too much of it at once. When you put paint on the wall, gravity starts to work against you, and what was once a flat layer can quickly drip down if it’s too thick. Another possible reason is that you’ve used the wrong type of paint for the project.

Do you want to know more reasons why your paint is dripping and how to prevent this? Read on to learn more.

What Is Paint Sagging?

Paint sagging is an undesirable paint defect that can occur when applying a thick layer of paint to vertical or inclined surfaces.

It is characterized by the paint film’s downward movement or “dripping” after application, resulting in an uneven coating with a thicker lower edge.

This problem often arises due to the separation of pigments if containers are kept for an extended period or exposed to extreme heat. Additionally, improper thinning and a lack of stirring or shaking can also be contributing factors.

Importance of understanding the cause of paint sagging

Understanding the cause of paint sagging is vitally important for any painting job to be successful. This is because sagging paint can create an unappealing finish and lead to premature wear and tear on surfaces, as well as structural damage in some cases.

Furthermore, if left untreated, sagging paint can allow moisture and other contaminants to penetrate the surface, leading to further issues.

Symptoms of paint sagging

The most obvious symptom of paint sagging is rough patches raised above the surface they were applied to.

These patches may appear lumpy or saggy due to the separation of paint from its underlying surface. This damage is usually most noticeable on walls or ceilings that have been recently painted.

Another sign of paint sagging is cracking or flaking off in small pieces, which can result from using inferior products or applying too thick a layer during application.

Also, bubbling or blistering can occur if there is too much moisture in the air during painting. This moisture will cause bubbles to form underneath the dried layers of paint and cause them to eventually peel away from the wall or ceiling. 

7 Causes of Sagging Paint

1. Paint sagging caused by poor preparation 

One of the most common causes of paint dripping is poor preparation. If your surfaces are not properly cleaned and primed before painting, then there’s a good chance that your paint won’t adhere to the surface correctly.

This will result in a sloppy finish with uneven coverage and sagging areas. To avoid this, ensure all surfaces are thoroughly cleaned before painting and use a quality primer for added adhesion. 

2. Environmental factors 

The environment in which you’re painting can also affect your finish. Excessive humidity or temperature fluctuations can cause your paint to dry too quickly or not, resulting in dripping.

To minimize this issue, try to keep the temperature consistent while painting and consider using a dehumidifier if necessary. 

3. Incorrect application technique   

Another possible explanation for paint sagging is improper application technique. Applying too much pressure on your roller or applying thick layers of paint can lead to sagging and bubbling and cracking once it dries.

To avoid this problem, make sure that you’re using light strokes when rolling out your color, and don’t overload your roller with too much product at once.

4. Applying a thick layer

When painting surfaces more than a few feet tall, it’s important to use thin layers and allow each one to dry completely before applying the next. This will help ensure that the paint adheres evenly and not be prone to dripping or running.

5. Using paint with a slow drying time

Sometimes, you may notice that your paint takes a long time to dry. This could be due to the type of paint you’re using.

If the paint has a slow drying time, it’s not ideal for use on vertical surfaces as it tends to sag and drip. Instead, opt for a faster-drying paint or one with a longer open time.

6. Poor workmanship

In some cases, paint sagging can be caused by poor workmanship. If the painter is applying thick layers of paint or not allowing enough time for each layer to dry completely before adding more, then sagging is likely to occur.

To ensure a professional finish, always make sure that you’re following the manufacturer’s instructions and taking your time when painting.

7. Improper thinning and lack of stirring or shaking

Lastly, improper thinning and a lack of stirring or shaking can also be contributing factors. If the paint hasn’t been properly thinned before use, it may cause sagging due to its higher viscosity.

Additionally, if the paint isn’t stirred or shaken properly before use, it may not be evenly distributed throughout the can, which can cause sagging.

How to Fix Sagging Paint

Fortunately, you can effectively prevent and remedy paint sagging with the following step-by-step guide:

Step 1: Clean up the drips while still wet

If you can catch the drip from a painting job while the paint is still wet, there’s a better chance it can be fixed with a few brush strokes.

However, if you find the paint already tacky and slightly dry to the touch, resist the temptation to brush against it.

Brush gently in the same direction as previously applied to ensure that no cross-strokes are put onto the wall, which can produce an uneven finish.

Step 2: Sand it down

Once the paint has had time to dry, you can reduce the raised area caused by the drip. A clean scraper, razor blade, or 5-in-1 tool can lightly scrape away any prominent parts of the drip.

Take care not to disrupt too much of the surrounding paint with this step. Next, switch to 220-grit sandpaper and lightly sand in one direction only.

Again, your aim should be solely on the raised area. Take extra precautions not to damage other parts of the paint job with stray sanding motions. If done correctly, your end product should reflect a smooth surface with as little evidence left from the original drip as possible.   

Step 3: Repair any damage left 

Once satisfied with the results from sanding, you can begin to touch up any disrupted or damaged areas.

Apply putty on any shallow marks left from the sanding process, and then use a primer to ensure that the touched-up areas match the surrounding paint job. Finally, you can apply a new layer of paint to blend with the existing coat.

Step 4: Repaint

When the drip is completely leveled, apply another coat of paint or two. After the paint dries, it will be nearly impossible to detect any blemishes.

How to Prevent Sagging Paint

Use high-quality paint

The quality of your paint plays a big role in preventing sagging. Make sure to use high-quality paint for the best results. This means investing in premium brands or picking up higher-priced paints with better coverage and less dripping.

Additionally, follow the manufacturer’s instructions, as the instructions will tell you the best method of thinning and stirring the paint for optimal results.

Check the temperature

Ensure your painting area is at a consistent temperature to prevent sagging. The more humid or hot it is in your space, the more likely your paint will droop or drip during application.

If necessary, invest in an air conditioner or dehumidifier to keep the temperature and humidity levels at a comfortable level.

Keep your brushes clean

When painting, make sure to keep your brushes clean at all times so that the bristles don’t become clogged with dried paint or debris from previous coats of paint.

This will help ensure that your brush applies a smooth layer of paint without leaving any patches or lumps behind on the wall. 

Don’t overload your brush

When applying paint onto a wall, it’s important not to overload your brush with too much product as this can cause drips and runs down the wall once gravity takes effect.

Instead, apply thin layers of paint using shorter strokes until you get an even coat with minimal dripping or running down the walls as you go along. 

Use proper techniques

Ensure that you’re using light strokes when rolling out your color, and don’t overload your roller with too much product at once.

If you need to apply thick layers of paint, ensure that you give each layer enough time to dry before adding more. Additionally, it’s important to stir the paint before use and thin it out with a solvent to prevent sagging.

Joshua Milton

I want to share everything I know about home improvement in order to help you. Whether you're a home enthusiast or an industry professional, I have the information that you need.

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