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 How to Diagnose & Evaluate Vertical Foundation Cracks
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InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
Foundation cracks and movement are discussed by type and location of foundation cracks,
vertical foundation cracks, horizontal cracks, and diagonal foundation cracks, and shrinkage cracking. This chapter of the "Foundation Crack Bible" discusses in detail the process of recognizing & evaluating vertical foundation
cracks and foundation damage. Foundation cracks, which are signs of foundation damage, can mean very different things
depending on the material from which a foundation is made, the location, size, and shape of the foundation crack, and
other site observations.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
VERTICAL FOUNDATION CRACKS - Vertical Foundation Crack Patterns
In the photos shown here, substantive cracks appeared and continued to increase in size in this poured concrete foundation
used to support a modular home which had recently been completed. The cracks and foundation movement were probably due to
a combination of: poorly prepared foundation footings, blasting on an adjacent building lot to prepare that site for new construction,
and possibly omission of steel reinforcement in the poured wall.
The cracks in this building foundation wall were visible shortly after construction as vertical hairline openings (less than 1/16" wide) in the right hand
foundation wall, above grade and inside in the basement. Within a year the owner reported several times
that the cracks were becoming noticeably wider.
A careful inspection of the building interior suggested that the
front foundation wall and portions of the right foundation wall were settling. There were no corresponding cracks in the finished
surfaces of the structure, probably because this was very stiffly-framed modular construction. Notwithstanding
the absence of damage upstairs, this was a problem that deserved further evaluation and repairs.
The builder may have repaired the foundation by supporting it from below using one of the methods described at FOUNDATION REPAIR METHODS.
This settlement crack probably occurred during initial footing settlement. Notice that it is wider at the top than the bottom of the
crack.
This suggests that the footing to the left or right of the crack has moved downwards, with further downwards movement as we move
further from the crack itself.
If this is new construction and the crack does not change in width the site conditions may have stabilized. |
How to Diagnose the significance of types of vertical cracks in foundations
- Vertical foundation cracks in masonry between two structures - differential settlement or thermal movement, often seen where an add-on garage
is built on more shallow footings on backfill next to a full foundation.
- Vertical, nearly straight or wandering cracks in poured concrete, generally even width, intermittent, or more often straight - shrinkage / thermal - low risk
- Vertical cracks, straight generally even width, in a masonry block wall, in mortar joints but possibly right through concrete block - shrinkage / thermal - low to modest risk
- Vertical foundation cracks that are straight or stepped in brick, especially near ends of wall - expansion / thermal, potentially dangerous if wall bond courses are broken, collapse risk.
- Vertical cracks in a foundation wall, wider at bottom than top - settlement under building. These cracks may be less serious than horizontal when found in a masonry block wall.
These cracks could be quite serious when found in a brick wall, especially if bond courses are broken and there is risk of collapse.
- Vertical cracks in a foundation wall, uniform in width, one side of crack/wall higher than the other: differential settlement in footings,
possibly a serious defect; this crack may have the same cause as the tapered crack above but suggests that the footing has both broken and
settled straight down at one side of the crack
Multiple vertical cracks in building foundations
Vertical foundation cracks often appear in multiples multiple cracks in one or more area.
While a vertical foundation crack could be serious depending on its cause and on the type of foundation in which it appears
(stone, brick, masonry block, concrete), these are often the least threat to the building. If there is significant vertical
dislocation or signs of ongoing movement, further investigation is more urgent. If the cause is shrinkage (concrete, masonry block)
it is probably less of a concern than if due to settlement. A vertical crack due to earth loading or frost would be unusual.
Frequently Asked Questions (FAQs) about the cause & severity of vertical cracks in building foundations
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
- Avongard foundation crack progress chart for structural crack monitoring
- Building Pathology, Deterioration, Diagnostics, and Intervention, Samuel Y. Harris, P.E., AIA, Esq., ISBN 0-471-33172-4, John Wiley & Sons, 2001 [General building science-DF] ISBN-10: 0471331724
ISBN-13: 978-0471331728
- Building Pathology: Principles and Practice, David Watt, Wiley-Blackwell; 2 edition (March 7, 2008) ISBN-10: 1405161035 ISBN-13: 978-1405161039
- Diagnosing & Repairing House Structure Problems, Edgar O. Seaquist, McGraw Hill, 1980 ISBN 0-07-056013-7 (obsolete, incomplete, missing most diagnosis steps, but very good reading; out of print but used copies are available at Amazon.com, and reprints are available from some inspection tool suppliers). Ed Seaquist was among the first speakers invited to a series of educational conferences organized by D Friedman for ASHI, the American Society of Home Inspectors, where the topic of inspecting the in-service condition of building structures was first addressed.
- Design of Wood Structures - ASD, Donald E. Breyer, Kenneth Fridley, Kelly Cobeen, David Pollock, McGraw Hill, 2003, ISBN-10: 0071379320, ISBN-13: 978-0071379328
This book is an update of a long-established text dating from at least 1988 (DJF); Quoting:
This book is gives a good grasp of seismic design for wood structures. Many of the examples especially near the end are good practice for the California PE Special Seismic Exam design questions. It gives a good grasp of how seismic forces move through a building and how to calculate those forces at various locations. THE CLASSIC TEXT ON WOOD DESIGN UPDATED TO INCLUDE THE LATEST CODES AND DATA. Reflects the most recent provisions of the 2003 International Building Code and 2001 National Design Specification for Wood Construction. Continuing the sterling standard set by earlier editions, this indispensable reference clearly explains the best wood design techniques for the safe handling of gravity and lateral loads. Carefully revised and updated to include the new 2003 International Building Code, ASCE 7-02 Minimum Design Loads for Buildings and Other Structures, the 2001 National Design Specification for Wood Construction, and the most recent Allowable Stress Design.
- Building Failures, Diagnosis & Avoidance, 2d Ed., W.H. Ransom, E.& F. Spon, New York, 1987 ISBN 0-419-14270-3
- Domestic Building Surveys, Andrew R. Williams, Kindle book, Amazon.com
- Defects and Deterioration in Buildings: A Practical Guide to the Science and Technology of Material Failure, Barry Richardson, Spon Press; 2d Ed (2001), ISBN-10: 041925210X, ISBN-13: 978-0419252108. Quoting:
A professional reference designed to assist surveyors, engineers, architects and contractors in diagnosing existing problems and avoiding them in new buildings. Fully revised and updated, this edition, in new clearer format, covers developments in building defects, and problems such as sick building syndrome. Well liked for its mixture of theory and practice the new edition will complement Hinks and Cook's student textbook on defects at the practitioner level.
- Guide to Domestic Building Surveys, Jack Bower, Butterworth Architecture, London, 1988, ISBN 0-408-50000 X
- "Avoiding Foundation Failures," Robert Marshall, Journal of Light Construction, July, 1996 (Highly recommend this article-DF)
- "A Foundation for Unstable Soils," Harris Hyman, P.E., Journal of Light Construction, May 1995
- "Backfilling Basics," Buck Bartley, Journal of Light Construction, October 1994
- "Inspecting Block Foundations," Donald V. Cohen, P.E., ASHI Reporter, December 1998. This article in turn cites the Fine Homebuilding article noted below.
- "When Block Foundations go Bad," Fine Homebuilding, June/July 1998
- Quality Standards for the Professional Remodeling Industry, National Association of Home Builders Remodelers Council, NAHB Research Foundation, 1987.
- Quality Standards for the Professional Remodeler, N.U. Ahmed, # Home Builder Pr (February 1991), ISBN-10: 0867183594, ISBN-13: 978-0867183597
- Slab on Grade Foundation Moisture and Air Leakage, U.S. Department of Energy
Technical Reviewers
- Sal Alfano - Editor, Journal of Light Construction*
- Thanks to Alan Carson, Carson Dunlop, Associates, Toronto, for technical critique and some of the foundation inspection photographs cited in these articles
- Terry Carson - ASHI
- Mark Cramer - ASHI
- JD Grewell, ASHI
- Duncan Hannay - ASHI, P.E. *
- Bob Klewitz, M.S.C.E., P.E. - ASHI
- Ken Kruger, P.E., AIA - ASHI
- Bob Peterson, Magnum Piering - 800-771-7437 - FL*
- Arlene Puentes, ASHI, October Home Inspections - (845) 216-7833 - Kingston NY
- Greg Robi, Magnum Piering - 800-822-7437 - National*
- Dave Rathbun, P.E. - Geotech Engineering - 904-622-2424 FL*
- Ed Seaquist, P.E., SIE Assoc. - 301-269-1450 - National
- Dave Wickersheimer, P.E. R.A. - IL, professor, school of structures division, UIUC - University of Illinois at Urbana-Champaign School of Architecture. Professor Wickersheimer specializes in structural failure investigation and repair for wood and masonry construction. * Mr. Wickersheimer's engineering consulting service can be contacted at HDC Wickersheimer Engineering Services. (3/2010)
- *These reviewers have not returned comment 6/95
Technical Edits, Changes, Amendments to This Document
- 9/23/2006 editing to clarify text and add content; Technical review (partial) by Arlene Puentes.
- 4/17/2006 editing to clarify text in several sections.
- 2/6/99 editing updates, soliciting additional reviews
- 2/3/99 Converted working text file to MSWord97 .doc and .htm files for easier review on Internet
- 6/26/95 text updates per comments from Al Carson, Terry Carson, Mark Cramer 6/16/95 text updates for Calgary July 1995
- cc's sent to reviewers
- 3/28/95 uploaded to ASHI's Internet site - asfoun01.txt
- 11/19/93 Ed Seaquist - telecon 11/19/93, likes, will write up one of our sections for my/our target of series of journal articles or a book.
- © Dan Friedman 2013, 1999, original 1992 All Rights Reserved -- foundation.htm
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
 The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
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- Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
- The Journal of Light Construction has generously given reprint permission to InspectAPedia.com for certain articles found at this website. All rights and contents to those materials are ©Journal of Light Construction and may not be reproduced in any form.
- Straw Bale Home Design, U.S. Department of Energy provides information on strawbale home construction - original source at http://www.energysavers.gov/your_home/designing_remodeling/index.cfm/mytopic=10350
- More Straw Bale Building: A Complete Guide to Designing and Building with Straw (Mother Earth News Wiser Living Series), Chris Magwood, Peter Mack, New Society Publishers (February 1, 2005), ISBN-10: 0865715181 ISBN-13: 978-0865715189 - Quoting:
Straw bale houses are easy to build, affordable, super energy efficient, environmentally friendly, attractive, and can be designed to match the builder’s personal space needs, esthetics and budget. Despite mushrooming interest in the technique, however, most straw bale books focus on “selling” the dream of straw bale building, but don’t adequately address the most critical issues faced by bale house builders. Moreover, since many developments in this field are recent, few books are completely up to date with the latest techniques.
More Straw Bale Building is designed to fill this gap. A completely rewritten edition of the 20,000-copy best--selling original, it leads the potential builder through the entire process of building a bale structure, tackling all the practical issues: finding and choosing bales; developing sound building plans; roofing; electrical, plumbing, and heating systems; building code compliance; and special concerns for builders in northern climates.
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