Can You Stucco Over Painted Cinder Block?

Stucco is a durable and long-lasting material resistant to weathering and deterioration. It is commonly used as an exterior finish, but can you install it over painted cinder blocks? We did thorough research to answer your question. 

Stucco can be applied over painted cinder blocks if the latter is in good condition without cracks. To ensure the stucco stays firmly on the wall, it is recommended to use a bonder. Before applying, you should make a rough surface on the block with sandpaper or a grinder. 

Stucco has several benefits as an exterior finish material. Keep reading, as we have also answered other related questions about stucco installation. 

Can You Apply Stucco Over Painted Cinder Blocks?

House brick wall renovation

Stucco can be applied over most painted surfaces in the home. Installing stucco over the painted cinder block is possible if applied correctly, and a bonder is used to ensure it adheres. 

It should also be smoothed and finished to give a seamless appearance. There are different advantages of applying stucco. It is relatively low maintenance, requiring only occasional cleaning and sealing to maintain its appearance.

It is also energy efficient, as it has good insulating properties and can help to keep a home warm in the winter and cool in the summer. Additionally, stucco is resistant to fire and pests, making it a durable choice for home construction.

What Are The Three Layers of Stucco?

To apply stucco successfully, you should understand the different layers. Here you have the breakdown of the three layers of stucco for installation.

The Scratch Coat

As the name implies, the scratch coat is the first layer of stucco you apply to the building. To make the scratch coat, you must mix sand, hydrated lime, and portland cement.

You can use a trowel to spread the mixed substances over the surface evenly. Get the scratch done with a scarifier to ensure the surface is well prepared for the second layer/coat to adhere to the base firmly.

Check out this scarifier on Amazon.

The Brown Coat

Unlike the scratch coat, the brown coat is smooth and has an equal appearance. Use your trowel to make the brown coat smoother than the firstly applied coat.

Priming stucco helps make a smooth surface design for the final finishing to be firmly adhered to. When you do not prime the stucco before giving the final touch, it will lead to poor adherence to the surface, eventually affecting the durability of the stucco.

Check out this plaster trowel on Amazon.

The Finish Coat

The finish coat is the finishing stage where you give your building the final and astonishing look you want. This is applied after the brown coat and is mainly done with a trowel or specially-made finishing tool to make the final design and texture you wish to have on the surface.

The final coat can sometimes contain pigments or other additives for aesthetic purposes. 

How Thick Should Stucco Be Over Block?

Abstract white color acrylic wave wall painting

Since stucco is applicable on both concrete and cinder blocks, the critical determinant of the thickness of stucco will be the type of stucco being used, and the smoothness of the surface to which it is being applied.

Here is a breakdown of the depth of stucco over the block in order of the three layers for the application stated:

  • The depth of the first/scratch coat should be over 3/8 inch. This ensures that the next coat has a soft lander on the scratch coat.
  • The brown coat, the second layer, should be applied at a depth of over 3/8 to 5/8 inch.
  • The third coat should be applied at a thickness rate of over 1/8 to 3/16 inches.

How Do You Waterproof Painted Cinder Blocks?

Stucco on a building wall

To waterproof your cinder blocks, you need a sealer. Making your cinder blocks resistant to water should start before applying the paint. Below are the steps to waterproof painted cinder blocks. 

  • Thoroughly clean the surface with a pressure washer. Scrub brush and water can also do the magic cleaning for you. The bottom line is to ensure you wipe away every debris or dirt on the surface.
  • Let the block dry off totally before applying the paint.
  • Create a rough surface for the paint to fit properly on the surface. Using fine-grit sandpaper will do this step. 
  • Use a paint roller or paint brush to apply a coat of water-resistant sealer on the cinder blocks’ surface.
  • Patiently wait for the sealer to dry off.

These are simple steps to waterproof your cinder block. However, making the painted cinder blocks water-resistant does not guarantee they would be completely free from water.

Water can penetrate through small cracks, and this will affect the paint. 

How Do You Cover Old Cracked Painted Concrete Walls?

There are several ways to correct, amend, or cover old painted concrete walls if they crack up. Drywall, paneling, tiling, applying wallpaper, and others are part of the ways to cover old painted concrete walls. But here are steps to follow to have your old cracked walls fixed up:

Step 1: Remove Old Paint From The Wall And Clean

Use a scraper to scrape off the old paint on the wall to have a perfect starting for the fixing. Carefully and thoroughly clean the concrete wall with a trisodium phosphate solution (TPS) and a scrub brush. This ensures you remove any oil or grease substance on the wall.

Step 2: Fill any and every hole on the wall

Fill up cracks on the wall. Hydraulic cement is especially effective here. Run a thorough check on the wall to ensure it is properly sealed to avoid openings. 

Step 3: Re-apply the Paint

Apply new paint on the wall. You can also use concrete stain to ensure you create a new look on the wall. 

How To Remove Paint From Concrete

Fresh concrete wall in the construction site, Can You Stucco Over Painted Cinder Block?

The amount of time it takes to remove paint from concrete will depend on several factors, including the type of paint and the age of the paint, In general, it can take anywhere from a few hours to a few days to remove paint from concrete. Here are some methods you can do. 

Use a Paint Stripper

There are several paint strippers that are specially designed to be used on masonry and concrete surfaces. Get a paint stripper that can remove both oil and water-based paints. This method can be more time-consuming since it could take several days, depending on the amount of paint present and the condition of the concrete.

Use a Pressure Washer

If the paint is fresh, it may be relatively easy to remove using a pressure washer for as little as a few hours. Soda blasting should also do the trick. With high pressure, thoroughly blast sodium bicarbonate on the affected spot and correct the error. This method does not affect the concrete strength or durability.

Use Vinegar

Vinegar works effectively to help remove water-based and oil-based paints from concrete. It is an eco-friendly and natural substance to strip paint. Due to the hardness of the concrete wall, vinegar remains one of the best solutions to apply for paint removal.


Peeling green paint plaster over concrete cinder block wall

Stucco is a popular choice for home construction due to its durability, energy efficiency, aesthetics, low maintenance, and fire resistance. Installing stucco over painted cinder blocks is possible if done correctly following the abovementioned steps. Thanks for reading. 

If you would like to learn more about stucco and home construction, check out these related articles:

At What Temperature Can You Apply Stucco? 

How Long Does Stucco Last? 

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