FHB Logo Facebook LinkedIn Email Pinterest Twitter X Instagram Tiktok YouTube Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe
Log In
  • How-To
  • Design
  • Tools & Materials
  • Restoration
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
Log In
How-To

Cracked Foundations

Prevention is easier than repair.

By Kip Park Issue 48
  • X
  • facebook
  • linkedin
  • pinterest
  • email
  • add to favorites Log in or Sign up to save your favorite articles

Synopsis: Cracked concrete foundations are a common building problem. This article explains the causes, covering subsurface soil conditions, concrete placement, and other contributing factors. A sidebar explains how cracks can be repaired with epoxy.

Throughout much of North America, homeowners face a similar problem—the cracking concrete foundations supporting their houses. The results are rarely life-threatening, but can be plenty uncomfortable. Water seeps into basements, plaster in the house cracks, and doors jam.

There’s no doubt that the problem is widespread. A 1981 survey by Owens-Corning Fiberglas Corporation of over 31,000 families throughout the U.S. found 59% of the households reporting leaky basements. A similar survey here in Canada in 1983 (by the University of Manitoba civil engineering department) found that over 70% of the houses surveyed had cracks in their basement floors, interior walls, and ceilings, with major cracks in 9% of the houses. Cracks in foundations are a particular problem in areas where there are expansive soils. Poor construction practices can also cause major problems with cracking.

Unruly substrates

Expansive soils are found throughout North America, but are particularly common here in Winnipeg, which is located on a former glacial lake bottom. Lake Agassiz was formed during the last Ice Age and covered about 180,000 sq. mi. of what is now Manitoba, Saskatchewan, North Dakota, and Minnesota. When the lake vanished about 7000 years ago, a layer of silt and clay which varies in thickness between 15 ft. and 40 ft. was left behind.

Lake Agassiz clay, like most clays, changes in volume as soil moisture levels change. According to Prof. Len Domaschuk of the University of Manitoba civil engineering department (who conducted the Winnipeg foundation survey), a layer of clay one foot thick will change about an inch in thickness as it alternates between dehydration and saturation. As it swells, clay can exert over 10,000 lb. of pressure per sq. ft. against a foundation.

A National Research Council of Canada study in Winnipeg between 1962 and 1966 found that the elevation of the ground surface fluctuated by 5 in. during that period, with vertical movements of 3 in. at 5 ft. below grade. A house built on this unruly substrate with its foundation footings 5 ft. below grade will therefore heave or settle up to 3 in. as moisture levels change. The house will sit still only if the moisture level is stabilized.

Controlling soil moisture

There are some basic and inexpensive measures that can be taken to minimize changes in the moisture content of the soil.

Lots shouldn’t be completely cleared of shrubs and trees, as they often are in subdivisions. Roots take moisture from the soil, and when they’re removed, soil moisture levels increase and the soil swells. A new concrete foundation placed in this swelling soil will almost always crack, especially if the concrete hasn’t reached its full design strength—and often it hasn’t.

Conversely, trees shouldn’t be planted too near a foundation. They should be kept at least 15 ft. away, otherwise they’ll cause the clays against the house to shrink excessively and cause the house to settle. If there’s a tree right next to the foundation, remove it.

For more photos and details, click the View PDF button below:

Sign up for eletters today and get the latest how-to from Fine Homebuilding, plus special offers.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters
×

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters
View PDF

New Feature

Fine Homebuilding Forums

Ask questions, offer advice, and share your work

  • X
  • facebook
  • linkedin
  • pinterest
  • email
  • add to favorites Log in or Sign up to save your favorite articles

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Up Next

Video Shorts

Featured Story

FHB Podcast Segment: Finding Hazardous Materials in a Fixer-Upper

Look closely at these common locations for hazardous materials in older homes.

Featured Video

How to Install Exterior Window Trim

Learn how to measure, cut, and build window casing made of cellular PVC, solid wood, poly-ash boards, or any common molding material. Plus, get tips for a clean and solid installation.

Related Stories

  • Old House Air-Sealing Basics
  • A New Approach to Foundations
  • Pressure Washing Made Portable
  • Beat the Heat: Cool Innovations

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

Video

View All Videos
  • FHB Podcast Segment: Designing and Building an Efficient Slab-On-Grade Home
  • FHB Podcast Segment: Is Foam Against Form Boards a Good Idea for a Garage Slab?
  • FHB Podcast Segment: Lime Wash Recipe for an Old Concrete Basement
  • FHB Podcast Segment: Masonry Chimney Care 101
View All

Maintenance and Repair

View All Maintenance and Repair Articles
  • Restoring Polychromed Light Fixtures
  • Rescuing Old Hardware
  • Fixing the Bullnose on a Concrete Step
  • Roll-Up Boardwalk
View All Maintenance and Repair Articles

Fine Homebuilding Magazine

  • Issue 332 - July 2025
    • Custom Built-ins With Job-Site Tools
    • Fight House Fires Through Design
    • Making the Move to Multifamily
  • Issue 331 - June 2025
    • A More Resilient Roof
    • Tool Test: You Need a Drywall Sander
    • Ducted vs. Ductless Heat Pumps
  • Issue 330 - April/May 2025
    • Deck Details for Durability
    • FAQs on HPWHs
    • 10 Tips for a Long-Lasting Paint Job
  • Issue 329 - Feb/Mar 2025
    • Smart Foundation for a Small Addition
    • A Kominka Comes West
    • Making Small Kitchens Work
  • Issue 328 - Dec/Jan 2025
    • How a Pro Replaces Columns
    • Passive House 3.0
    • Tool Test: Compact Line Lasers

Fine Home Building

Newsletter Sign-up

  • Fine Homebuilding

    Home building tips, offers, and expert advice in your inbox.

  • Green Building Advisor

    Building science and energy efficiency advice, plus special offers, in your inbox.

  • Old House Journal

    Repair, renovation, and restoration tips, plus special offers, in your inbox.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters

Follow

  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X
  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences
  • About
  • Contact
  • Advertise
  • Careers
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2025 Active Interest Media. All rights reserved.

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

  • Home Group
  • Antique Trader
  • Arts & Crafts Homes
  • Bank Note Reporter
  • Cabin Life
  • Cuisine at Home
  • Fine Gardening
  • Fine Woodworking
  • Green Building Advisor
  • Garden Gate
  • Horticulture
  • Keep Craft Alive
  • Log Home Living
  • Military Trader/Vehicles
  • Numismatic News
  • Numismaster
  • Old Cars Weekly
  • Old House Journal
  • Period Homes
  • Popular Woodworking
  • Script
  • ShopNotes
  • Sports Collectors Digest
  • Threads
  • Timber Home Living
  • Traditional Building
  • Woodsmith
  • World Coin News
  • Writer's Digest
Active Interest Media logo
X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Project Guides
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Online Learning

  • Courses
  • Project Guides
  • Reader Projects
  • Podcast

More

  • FHB Ambassadors
  • FHB House
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • X
  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 70%

Subscribe

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in

Privacy Policy Update

We use cookies, pixels, script and other tracking technologies to analyze and improve our service, to improve and personalize content, and for advertising to you. We also share information about your use of our site with third-party social media, advertising and analytics partners. You can view our Privacy Policy here and our Terms of Use here.

Cookies

Analytics

These cookies help us track site metrics to improve our sites and provide a better user experience.

Advertising/Social Media

These cookies are used to serve advertisements aligned with your interests.

Essential

These cookies are required to provide basic functions like page navigation and access to secure areas of the website.

Delete My Data

Delete all cookies and associated data