Ask an Expert: Construction Defects

Ask An Expert is a question-and-answer column designed to address common questions related to forensic investigation and property damage. Each month we’ll feature one or two questions submitted by you – our readers and customers – and provide detailed, easy-to-understand answers. Email your questions to [email protected] or submit your questions here.


Q: Is there any benefit to completely sealing a crawlspace and creating a dry space?

A: Yes, this is referred to as an encapsulated crawlspace. Many crawlspaces are being retrofitted with encapsulation systems to address moisture issues.

Q: What’s the difference between spalling and efflorescence?

A: Efflorescence occurs when moisture migrates through masonry and dissolves minerals in the masonry material.  When the moisture reaches the inside face of the masonry, the moisture evaporates, leaving the minerals on the face of the masonry.  Over a long period of time, the buildup of minerals creates a white discoloration known as efflorescence. Spalling occurs when masonry absorbs water and that water freezes and expands. The face of the masonry spalls or breaks off.

Q: Can a product like flex seal be applied to the interior of the wall in the crawlspace to prevent moisture?

A: Yes, according to the manufacturer’s website, flex seal can be applied to basement walls. However, we consider this a temporary solution that does not address the underlying problem.

Q: What impact does mis-nailing shingles on an angle have?

A: This can result in raised shingles, unsealed shingles, and it may cause the shingles to be less resistant to wind uplift.

Q: What impact does overdriven fasteners have?

A: Overdriven fasteners can have the same problems as a poor nailing pattern, which may result in sliding shingles, less resistance to wind uplift, etc.



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About the Experts

Mr. Jeff Coyne joined Donan in 2006 as a forensic engineer based out of the firm’s Nashville, Tennessee office. His areas of expertise are residential and commercial roof inspections, structural assessments, moisture infiltration, and storm damage assessments. Mr. Coyne completes a wide range of projects at Donan related to flood, wind and tornado damage, earthquakes, hurricanes, crawlspace moisture, water intrusion, construction defects, and structural and foundation failures, among others. Mr. Coyne is a licensed professional engineer in Alabama, Arkansas, Florida, Georgia, Idaho, Indiana, Kentucky, Louisiana, Mississippi, North Carolina, New Jersey, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas and Virginia. He earned a Bachelor’s degree in Civil Engineering from Tennessee Technological University and a Master’s degree in Civil Engineering from the University of Tennessee – Knoxville.

View Jeff’s full professional profile here.

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