How To Clean and Prepare Exterior Stucco for Painting?

Stucco is a popular choice because of its texture.

It can also last quite a long time with minimal maintenance.

Considering that it is made from natural materials such as concrete, sand, and limestone, there are no toxic properties in the stucco.

However, its one downside is the very texture itself which allows for the collection of algae, dirt, grime, and mold.

Over time, all these elements may cause damage to the stucco.

They also prematurely age the stucco and make the area look old and unpleasant to view.

This is why you need to clean the stucco twice a year, sometimes three times a year to remove all such elements before they can take hold.

How to Clean Stucco – The Right Way

Stucco is a popular exterior finish for homes, but it can be difficult to paint.

If you’re planning on painting your stucco home, it’s important to clean the surface first.

What follows is a step-by-step process of how to clean exterior stucco…

Step 1- Inspection

The first step for cleaning before painting is to look over the stucco for any cracks, holes, or other damage.

Any opening in the stucco may allow water to seep through which in turn provides a feeding ground for mold and mildew.

Over time, mold and mildew can grow and damage the interior walls.

Plus, the more water that is let in, the more likely damage below the surface of the stucco is happening.

Step 2- Seal

Any hairline cracks and small chips can be repaired quickly by using caulk.

You’ll want to choose an exterior acrylic caulk that closely matches the color of the stucco.

You can find such caulk at home improvement centers and many local retailers as well as online.

Just clean the area of the opening, apply the caulk, and let dry.

To help match the texture of the caulk, you can mix in a little sand.

Apply the caulk first and then press in a little sand before it can dry.

This will create a more textured appearance and match the surface better.

You may not need sand if the cracks are indeed hairline.

Once the caulk is fully dry, then you can proceed to the cleaning phase.

However, if the damage to the stucco is more than caulking can fix, then you may need to call in a professional to do the job.

Step 3- Spray

Once all the caulk is fully dry, you can start the cleaning process by spraying the stucco with water.

Any loose dirt and debris will be rinsed away.

You can use your garden hose or a pressure washer to do the job.

Just be sure that the pressure washer is set for 1,500 PSI or less and use a nozzle that is angled from 25 to 40 degrees.

Pressure higher than 1,500 PSI may damage the surface.

Be sure to spray the stucco from at least two feet away to avoid any damage.

To properly rinse the surface, keep the nozzle at a 45-degree angle and use an even stream.

Step 4- Clean

To clean away the stains that may have formed on stucco, you will need to use a combination of dish soap and water.

This will loosen and help remove any stains that are present.

However, if there is mold or mildew on the stucco surface, then you will need to use a combination of bleach and water.

The bleach will kill the mold or mildew and allow it to be removed from the surface.

You can mix concentrated stucco cleaner with bleach to achieve the same effect.

Be sure to follow all instructions when using the concentrated stucco cleaner.

However, mixing bleach with water should be good enough for most cleaning on stucco.

In addition to removing any mold and mildew, the bleach will also eliminate any algae and rust stains as well.

The only caveat is that you will need to wear rubber gloves and goggles for protection when using bleach.

If you are not comfortable with using bleach, then you can try a mixture of dish soap and Borax.

Borax will remove mold and is not nearly as toxic compared to bleach.

Mix ½ cup of Borax with 2 tablespoons of liquid dish soap into two gallons of water.

You can apply the solution using a pressure washer.

Be sure to angle the nozzle downward at 65 degrees and keep it at least two feet from the surface.

Do not use more than 1,500 PSI on the pressure washer or you might damage the surface.

Once you have applied the cleaning solution, let it sit for about 10 minutes, but do not let it dry.

If it is trying quickly, lightly spray it with water every few minutes.

Step 5- Scrub & Rinse

Here – use a soft-bristle brush on the still-wet surface to remove any stains, algae, mold, or mildew.

You can use a hand brush or a rotating brush attachment, your choice.

The pressure you apply should be firm, but gentle to get the best results.

Once you have scrubbed the surface, rinse off the solution with pure water.

This will clean away all the residue and remaining unwanted elements from the surface of the stucco.

Start by rinsing from the top and working your way down.

This will ensure that all unwanted substances will be washed off the stucco completely.

Once again, keep the pressure washer nozzle at least two feet from the surface, do not use more than 1,500 PSI, and a 25 to 40-degree nozzle angle should work fine for this use.

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How Can You Remove Ivy Tendrils from Stucco?

It’s possible that you may have to repaint the stucco after removing the ivy because of the clean patches it leaves behind.

However, if you do not remove the ivy properly, it will take some of the stuccoes with it.

Therefore, you will need to use the right strategy to remove the ivy without damaging the stucco.

The first step is to snip away the root of the ivy using garden shears.

If the ivy is growing from the ground, snip at the ground level across the front of the stucco.

If the ivy is dangling from the trees, then cut the ivy from above.

It will grow back unless you find the roots, so you may have to snip every so often during the year.

Now, cut horizontally across the surface of the stucco, separating the ivy every 12 inches or one foot.

The goal is to create 12-inch sections of the ivy from bottom to top.

Next, cut vertical lines across the ivy until you have all the ivy cut into individual 12-inch sections.

Let the ivy dry up and die. This generally takes from two to four weeks.

Once it is dead, you can put on some leather gloves and gently pull want remains from the surface.

Any ivy that is still green and clinging should be left alone so it can dry up over the following weeks.

Any dead fragments, bird poop, or wasp nests (if any) can be removed using a soft bristle brush.

While bleach can kill the ivy relatively quickly, it will ruin the color of your stucco making it spotty and unsightly.

So, avoid using bleach and simply let the vines die naturally once they have been cut.

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Painting Exterior Stucco after all the Cleaning is Done?

Once the surface has been cleaned and dried, a coat of exterior masonry primer should be applied.

You can start with the edges first using a brush and then roll the rest of the primer on the stucco.

A thick nap roller tends to work best on uneven surfaces.

1- Use Roller Grid:

This is an inexpensive plastic grid that fits into a five-gallon bucket.

Once you have poured the primer into the bucket, dip the roller in and then lightly roll back up along the grid.

This action will remove the excess paint.

2- Apply Primer:

Cover the entire surface with a single coat of primer.

Stain-blocking primer is perfect if you have prominent stains on the stucco.

Remember to let the roller do its work. Do not press in too much.

You’ll want to distribute the primer as evenly as possible. Once completed, you’ll want to let the primer dry before applying the paint.

3- Apply the Exterior Paint:

Now you are ready to paint. Apply painter’s tape around the window trim and doors first.

Start with the areas around the doors and windows with a single coat of exterior masonry paint.

Use a brush to get all the edges correct. Next, use the roller and apply the paint to the surface much like you did the primer.

You can consider using the five-gallon bucket and a roller grid for the best results.

Let the first coat fully dry and add at least one more coat for maximum protection.

It is better to apply two light coats than one heavy coat of paint. This provides you with the best results.

4- Remove the Tapes:

Finally, once the second coat is fully dry and you do not need to add any more coats, be careful about removing the painter’s tape.

Use a straightedge alongside the edge of the paint and score the paint with a utility knife.

This will allow you to gently pull away tape without damaging the stucco.

TIP:

If you have really deep crevices in the stucco, you may want to spray on the paint instead of using a brush or roller.

If so, you’ll need to cover areas nearby that you do not want to paint. Plastic covers are generally the best.

Also, remember that it’s good to use a commercial sprayer and not a consumer one for the best results.

The Bottom Line

Stucco is a material that will hold the paint well.

So, to make the stucco look fresh and new again, you should reapply a coat of exterior paint once every 2-3 years.

For this, you will need to do a little preparation first which includes cleaning the old stucco and filling up any cracks with caulk.

Hopefully, the detailed tips above will help you get the job done in the right way.