How to Repair a Crumbling Cinder Block Foundation

April 20, 2023

Sharing is caring!

Homeowners especially often wonder how to repair a crumbling cinder block foundation. It’s vital to understand this subject, as foundation damage only gets worse the longer it’s ignored. Also, a crumbling foundation often lets a house sink, risking costly secondary damage.

In the vast majority of cases, it’s good to rely on a professional for foundation repair. Trained, experienced contractors ensure quality fixes that last and can address foundation damage causes. Also, they can ensure their own safety when working around crumbling foundations. However, property owners can address minor damage with the right tools and a bit of know-how.

how to repair crumbling cinder block foundation

What Is a Cinder Block Foundation?

To address a crumbling cinder block foundation at a residence, it helps to understand how they’re constructed. Contractors create cinder block foundations by stacking concrete blocks and coating them with mortar as they work.

Next, the contractor typically threads rebar through the hollow blocks and fills them with concrete. The contractor repeats this process until the blocks form the needed foundation. Contractors often use cinder blocks to create a basement or crawlspace under a home.

Cinder block foundations are different from poured concrete. To create a poured concrete foundation, a contractor starts with wood forms. Next, he or she mixes concrete and pours it into that form, allowing it to then dry over time. Poured concrete foundations then create one solid piece, as opposed to blocks mortared together.

Why Cinder Block Foundations Might Crumble

Foundation repair contractors typically agree that excess moisture is the number one risk to foundations. Cinder blocks absorb that moisture, which breaks down its binders and weakens the material. Also, moisture risks soil expansion. As the soil expands, it presses on a foundation, also risking cracks and other damage.

Additionally, note that this moisture can come from inside or outside the home. For instance, improper interior ventilation or plumbing issues risk a damp basement. Concrete blocks often absorb that moisture, leading to cracks and crumbling.

Moreover, concrete blocks absorb moisture trapped in a crawl space. High humidity levels and poor drainage risk damp crawl spaces and damaged blocks. Flooding and plumbing leaks along the home’s underside also mean moisture and crumbling cinder blocks.

repairing cinder block foundation

How to Repair Crumbling Cinder Blocks

Homeowners might tackle minor cracks and crumble with hydraulic cement. This cement works like mortar, binding block pieces together and providing a watertight seal. You can purchase this product at just about any hardware or home improvement store.

Also, you’ll need:

  • a bucket or pan for mixing the cement
  • a hammer and chisel
  • a wire brush
  • a shop vacuum
  • a trowel

If you’re working on painted blocks, you’ll also need some fresh paint to cover your repairs. A homeowner should also wear thick work gloves and eye protection. Lastly, keep pets and children away from the area to prevent mess and injury.

First, remove any crumbling material with your hammer and chisel. Second, use the wire brush to clean the area and the shop vacuum to remove dust and debris. Next, mix the hydraulic cement as instructed on the package. You can typically mix it with your trowel and create fresh batches as you work.

Then, apply the cement with your trowel, pushing it deep into all cracks and crevices. Use the edge of your trowel to remove excess cement and smooth it over as you work. Step back and check your work often to ensure you haven’t missed a spot. You also want to scrape or catch dripping cement quickly so it doesn’t dry on the walls or floors.

Check the package to note how long the cement needs to dry properly. Once it’s set, you can then sand it down and paint over it if desired. However, don’t rush this step, as wet cement absorbs paint, creating a splotchy finish.

One last note; call the professionals right away for bowing basement walls or crumbling crawl space piers. Both risks collapsing at any time. Carbon fiber straps push walls back into place while crumbling piers need replacing. These tasks are best left to a professional foundation contractor.

Tips for Preventing Future Cinder Block Foundation Damage

Moisture is often the number one risk to cinder blocks, as said. In turn, you might consider how to keep moisture away from a foundation and protect it from damage:

  • A professional contractor can apply waterproof membranes to cinder block foundations. If you can’t afford this service, consider coating interior basement walls with waterproof paint or other coatings.
  • For overly damp basements, install a dehumidifier. This appliance captures airborne humidity and keeps the space dry.
  • Crawl space encapsulation involves thick plastic sheeting installed over all exposed surfaces. Vapor barriers, installed only over the ground, are more affordable but slightly less effective. Both block moisture in the crawl space, protecting your home’s foundation.
  • Proper drainage is vital for keeping moisture away from a foundation. A repair contractor or experienced landscaper can check your property’s grade or slope. Increasing that slope can help direct moisture in the ground away from the structure.
  • Lastly, consider regular foundation inspections over the years. Spotting damage the minute it starts to form allows you to make prompt repairs.

Champaign Foundation Repair Experts is happy to help explain how to repair a crumbling cinder block foundation. Hopefully, you found this information informative. If so, be sure to check out our blog for more useful tips on foundation fixes and maintenance. Also, call our Champaign foundation repair contractors when it’s time for service on your home or commercial structure.

We can perform a FREE foundation inspection and prepare a price quote at your earliest convenience. For more information, use our callback form or just get in touch today.

Leave a Reply

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

In This Article:

linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram