Should You Paint Your Exterior Cinder Block Chimney?

Chimneys are a staple of the classic American home, whether or not it is still in use. Perched on the roof, you want your cinder block chimney to look good and function well. In this case, should you paint it? We have done the research and will give you answers!

While you can paint your exterior cinder block chimney, it isn't the best option. There are pros and cons to either choice, so your best bet is to prioritize what you aim to achieve with your chimney. In most cases, a paint job is done either for waterproofing or aesthetics.

The next sections will explain in detail to help you figure out if you should paint your chimney. We will also review the alternatives to painting a cinder block chimney and how to deal with common issues such as moisture. Read on to learn more!

Should You Paint Exterior Chimney?

Chimney clad with clinker bricks on a newly covered roof

You can paint an exterior cinder block chimney, but you should not always do so. There is a certain method for painting cinder blocks, and doing it incorrectly results in a waste of time and effort. If you know how to do it correctly, painting your cinder block chimney is something you can consider.

When it comes to chimneys, the general recommendation is not to paint the exterior. There is too much risk of damage to the material with how much the chimney is exposed to the elements. If you put a layer of paint, it does not guarantee that the masonry is fully safe.

Will Paint Seal Your Chimney?

Cinder blocks are highly absorbent due to how porous they are. They are bound to absorb moisture, be it from rain or just humidity. Do not confuse cinder blocks with concrete blocks. The latter is more water resistant. Without a seal, your chimney absorbs moisture over time. However, there is a better chance that the moisture will drain or evaporate without the seal. Painting an external chimney does not completely seal it. While it can decrease how much moisture gets in, it does not fully prevent it.

As we mentioned, another downside to sealing a chimney with paint is that the moisture can no longer come out as easily. The paint traps water inside, leading to bubbles and the cinder blocks breaking down. You can notice water damage on your chimney, even with paint. Rather than painting your exterior chimney, consider other options. If it's the color you're after, you can use a chimney stain to achieve your desired effect, though there are less options for customization with this approach.

How To Paint A Cinder Block Chimney

Worker of Industrial Alpinist Services painting chimney on the roof with paint spray gun. Professional climber wearing uniform, helmet and using safety harness. Risky job. Extreme occupation.

Cinder blocks are not common in modern homes. Since 1947, cinder blocks were no longer manufactured, though they are still rarely used today. Some building codes even prohibit the use of cinder blocks. They are more common in homes built before these building codes. That said, there are extra steps to preserve your chimney. As mentioned, painting your chimney the wrong way can lead to irreparable damage. If you can avoid painting it, opt for the alternatives discussed in the next sections.

If you do not think you can paint your chimney alone, ask for help or hire a contractor. A professional will be able to get the job done properly and will also save you the risk of having to work on the roof. Otherwise, here are the steps to painting your chimney yourself:

  1. Prepare the tools and materials. This includes tools for cleaning, latex or acrylic paint, a paint sprayer, roller, or brush, paint tray, soap, caulk, and drywall knife, among others. Don't forget the ladder!
  2. Clean the exterior to get the dirt and flakes out. Use a pressure washer or scrub manually. You can also hire someone to do the task for you.
  3. Remove the old paint. Use a paint stripper or sanding paper. If you do the former, you might rewash the chimney to eliminate any residue. Completely dry before painting.
  4. Make repairs that include caulking gaps and smoothing with a drywall knife. Let dry and cure completely.
  5. Add a protective covering to your roof. Now you can start priming and painting your chimney!
  6. Cover the cinder blocks with a layer of concrete and masonry bonding primer, which should be latex-based.
  7. Once the primer has set, proceed to paint. Use paint for exteriors and be heat-resistant. Apply one coat and let dry completely. You can recoat if needed. Two coats are enough.

Click here to see this primer on Amazon

Is It Normal For Water To Come In Chimney?

With a well-installed chimney cap and damper, you can keep water and moisture out of your home. It is not normal for water to come in through the chimney. If water is coming in anyways, this is a sign of a leak, and the the problem likely lies in the chimney cap. When working properly, it keeps rain or animals out of your chimney. If it is damaged, you will have to repair or replace it. If your chimney crack appears fine, then the leak could be coming from the sides of the chimney, such as a crack.

Fully intact chimneys can still leak due to the cinder blocks absorbing the moisture dripping down the chimney interior. This can be fixed by removing any damaged paint or resealing the exterior chimney. It is also a good idea to waterproof your chimney, even if you won't be painting it.

How Do You Waterproof A Chimney?

Smoke from the chimney, heating. smoke billowing. coming out of a house chimney against a blue sky background, Should You Paint Your Exterior Cinder Block Chimney

You can waterproof your chimney using products such as ChimneySaver or ChimneyRX. The steps to waterproofing are similar to painting with extra details. Here are the steps:

  1. Prepare your materials, which include cleaning equipment, repair equipment, spray applicator, and your water repellant of choice.
  2. Clean and let dry your chimney.
  3. Repair and reinforce chimney parts with damage. Seal any leaks and replace parts.
  4. Protect your roof. Avoid creating a slippery surface which is a safety hazard.
  5. Spray water repellent to the exterior. Follow the product instructions as indicated on the package or manual.

Click here to see this chimney water repellent on Amazon

What Are The Alternatives To Painting An Exterior Cinder Block Chimney?

When it comes to cinder block chimneys, you may be better off not painting the exterior. Instead, go for sealing and waterproofing. Embrace the look of the masonry. Chances are it will still look good against the exterior of your house.

If you want some color, consider staining the bricks Some companies produce a brick stain that is a much more breathable alternative to latex paints. After staining, you can go over the brick with waterproofing.

You can never go wrong with colors like black, shades of brown, and even some shades of red. These are good options for any chimney, and it is relatively easy to color cinder blocks this way. While lighter colors such as white, cream, and light gray are good, they must be painted on.

Some homes stop using chimneys altogether and rely on other means of heating. If your house is like this, you can block off your fireplace and keep it as a decorative piece. In this case, the chimney is purely for the aesthetics.

You will still need to waterproof and seal your chimney if it is not in use. It is still a part of your house, and a means for moisture and water to get in. As much as possible, do not neglect your chimney until it becomes a problem. Instead, maintain it regularly.

Which Types Of Chimneys Should You Paint?

Brick chimney stack on modern contemporary house roof top. Urban housing estate tiled roof in close-up.

When it comes to painting chimneys, you have to be careful with the material. All masonry, including brick, concrete, and cinder block, is porous. They are easy to paint, but you face the issue of moisture when you do.

On the other hand, you can paint a metal chimney. Examples of metal chimneys include aged copper, aluminum steel, and galvanized. These options are treated, but you can still paint them to add an extra layer against corrosion.

Note that you must use specialized primer when painting a chimney of any material. There are primers made for masonry and ones made for metal. The primer must also be able to withstand heat. The same goes for the type of latex paint you will be using.

Wrapping Things Up

Smoke from the chimney, heating. smoke billowing. coming out of a house chimney against a blue sky background

While you can paint an exterior cinder block chimney, it is not always recommended. Cinder blocks are porous and absorb moisture, so a layer of paint will damage the chimney structure. Instead of painting, you should seal or waterproof your chimney exterior with a good water repellent.

Did you find this post helpful? If you did, check out our other posts before you go!

Do Concrete Blocks Deteriorate?

Removing A Chimney 101 - How To Guide!

Leave a Reply

Your email address will not be published. Required fields are marked *