What's Under the House: Fill Dirt and Moisture Issues
When placed under a foundation, fill dirt is arguably the most important structural component of a home, and that fill dirt is the leading cause of new home structural failures.
Walt Keaveny, a professional engineer and geoscientist for 2-10 Home Buyers Warranty, explores fill dirt and offers tips for minimizing problems in a new NAHB Construction Liability resource, Let's Talk Dirt.
According to Keaveny, not only is fill dirt the most common cause of structural failure, it is also a very costly repair — nationwide it costs an average of over $50,000 to investigate and repair a structural failure caused by fill dirt. In some states the average cost exceeds $100,000.
Let's Talk Dirt provides information about fill placement, density requirements, testing, and the benefits of working with a geotechnical engineer.
Keaveny also explores moisture issues in basements in Ultimate Guide to STOP Basement Water Leaks. Over half of all basements have some moisture issues, with basement walls and floors the most common locations for water leaks in a home. Unlike improperly compacted fill dirt, water leaks in basements rarely represent a structural deficiency, according to Keaveny.
However, a water leak that is seen trickling is not normal, and it is beneficial to terminate the source of the water to avoid: (1) saturating soils that support the foundation, (2) rot and degradation of wooden framing, (3) damage to drywall and finishes, (4) damage to household items, (5) mold and (6) vermin.
To learn about the three major sources that cause water leaks, water migration into basements, damp proofing versus water proofing, and to view Keaveny’s Water Source Checklist, review the Ultimate Guide to STOP Basement Water Leaks.
Plus, you can stay current with the latest building materials and construction liability developments on the NAHB Construction Liability Resources page.
For any questions about construction liability, please contact David Jaffe.
Latest from NAHBNow
Aug 11, 2025
America’s Housing Supply Crisis: Is the Suburban Frontier Closing?A recent working paper titled “America’s Housing Supply Problem: the Closing of the Suburban Frontier?” dives into why the supply of new housing has shifted lower, especially in the sunbelt regions like Dallas, Atlanta and Phoenix.
Aug 08, 2025
Canadian Lumber Duties Hit 35% — And May Go Higher SoonThe U.S. Commerce Department announced today that it is more than doubling its countervailing duties on Canadian lumber imports from 6.74% to 14.63%.
Latest Economic News
Aug 11, 2025
Market Share for Modular and Other Non-Site Built Housing in 2024The total market share of non-site built single-family homes (modular and panelized) was just 3% of single-family homes in 2024, according to completion data from the Census Bureau Survey of Construction data and NAHB analysis.
Aug 08, 2025
Foundation Types in 2024: Slabs Continue to Rise, Crawl Spaces DeclineIn 2024, 73% of new single-family homes started were built on slab foundations, according to NAHB analysis of the U.S. Census Bureau’s Survey of Construction (SOC).
Aug 08, 2025
Weaker Demand for Residential Mortgages in Second QuarterIn the second quarter of 2025, overall demand for residential mortgages was weaker, while lending standards for most types of residential mortgages were essentially unchanged, according to the recent release of the Senior Loan Officer Opinion Survey (SLOOS).