Crumbling Foundations in Connecticut: What Every Homeowner Needs to Know

If you live in Connecticut, you've probably heard someone mention the words "crumbling foundation." Unfortunately, for thousands of homeowners, it's more than just a rumor—it's a very real and expensive problem.

At J. Mongillo Concrete Construction, we've had the opportunity to help homeowners restore their homes by replacing deteriorating foundations. While every project is unique, the end goal is always the same: give the home a brand-new foundation that's built to last.

What Is Connecticut's Crumbling Foundation Problem?

Between the early 1980s and approximately 2015, concrete supplied to many homes in eastern and northeastern Connecticut contained a naturally occurring mineral called pyrrhotite. The mineral wasn't intentionally added—it was present in crushed stone aggregate that came from a quarry supplying concrete during that time period. (CT.gov)

Over time, when oxygen and moisture reach the pyrrhotite inside the concrete, a chemical reaction begins. The reaction creates minerals that expand, causing the concrete to crack from the inside out. Unlike normal concrete cracks caused by settling or shrinkage, these cracks continue to worsen over the years as the deterioration progresses. (CT.gov)

Why Is It Mostly East of the Connecticut River?

The problem isn't simply that homes were built during a certain time period.

It's because many concrete suppliers serving eastern Connecticut sourced aggregate from a quarry whose rock contained elevated amounts of pyrrhotite. As a result, thousands of homes across Tolland, Windham, Hartford, and surrounding counties were affected. Experts estimate that as many as 35,000 homes, condominiums, and municipal buildings may have been impacted. (CT.gov)

Signs of a Crumbling Foundation

While every foundation is different, some common warning signs include:

• Horizontal, vertical, or spider-web cracking

• Map-like cracking patterns

• Concrete that flakes or crumbles

• White mineral deposits on foundation walls

• Bowing or deteriorating basement walls

• Water intrusion through cracks

A structural engineer or approved testing laboratory can determine whether pyrrhotite is present through visual inspection and, if needed, a concrete core sample. (CT.gov)

Can It Be Repaired?

Unfortunately, no.

Unlike a normal foundation crack that can sometimes be repaired with epoxy injection or reinforcement, concrete affected by pyrrhotite continues to deteriorate.

The only permanent solution is a complete foundation replacement.

How Do You Replace an Entire Foundation?

This is where things get really interesting.

Most people can't imagine replacing the foundation under an existing house.

The process begins with another specialized contractor who installs a structural lifting system and carefully raises the entire home off its existing foundation.

Yes—the entire house is literally lifted into the air and safely supported while the old foundation is removed.

Once the home is secure, our work begins.

Building a Brand-New Foundation Under an Existing Home

At J. Mongillo Concrete Construction, we approach these projects the same way we would a brand-new home.

The difference?

Instead of working on an empty lot...

We're working underneath a fully supported house.

We:

• Remove the deteriorated concrete foundation.

• Prepare and grade the site.

• Install new footings.

• Form and reinforce new concrete foundation walls.

• Place new concrete using today's quality standards and materials.

• Waterproof and prepare the foundation for the home to be lowered back into place.

It's essentially new home construction beneath an existing home—one of the most challenging and rewarding types of concrete work we perform.

Precision Matters

When you're pouring a foundation for a new home, there's no structure overhead.

With a lifted house above you, every measurement matters.

Every anchor bolt, wall elevation, opening, and dimension must line up perfectly so the home can be lowered back into place safely.

There's very little room for error.

That's why experience, planning, and quality craftsmanship are critical on every foundation replacement project.

Building It Better Than Before

Today's concrete mixes are produced under much stricter quality standards than decades ago.

Modern aggregate sources are carefully monitored, and Connecticut has implemented laws and testing requirements designed to help prevent this issue from happening again. (Connecticut General Assembly)

Our goal is to provide homeowners with a foundation that will support their home for generations.

Why We Love These Projects

Replacing an entire foundation is no small task.

It's demanding.

It's technical.

And yes—it still amazes us every time we stand underneath a house that's been lifted several feet in the air.

But there's something incredibly rewarding about watching a homeowner go from worrying about the safety and value of their home to knowing they have a brand-new foundation beneath them.

That's why we do what we do.

Need a Foundation Replaced?

If your home has a deteriorating concrete foundation or you're working with a house-lifting contractor that needs an experienced concrete foundation contractor, J. Mongillo Concrete Construction has the expertise to complete the job safely and professionally.

From new residential foundations to complete foundation replacements, we're proud to help Connecticut homeowners build on a solid foundation—literally.