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This website discusses How to Repair Damaged Foundations, Foundation Cracks, Slab Cracks, Bowed, Buckled, Leaning Foundation Walls, Settled Floors: The photo above shows a bowed masonry block foundation wall with horizontal cracking that occurred due to earth loading at the time of construction, probably by vehicles driving too close to the foundation wall shortly after it was constructed.

At this website we explain how it is sometimes possible to be confident about the cause of foundation damage which in turn helps assess the risk presented to the building and the repair methods needed for foundation damage, cracks, leaning, buckling, bowing, settlement. © Copyright 2010 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Repair Methods for Foundation Cracks

Repair Methods for Foundation Shrinkage Cracks

Before repairing a foundation crack it is important to diagnose the cause of the crack and its effects on the building structure. The significance of any foundation crack depends on the crack's cause, size, shape, pattern, location, foundation materials, extent of cracking, impact of the crack on the building, and possibly other factors as well. If there is an underlying ongoing problem causing foundation movement or damage, that problem needs to be corrected too. Cracks in poured concrete walls that are larger than 1/4", cracks which are increasing in size, or cracks which are otherwise indicative of foundation movement should be evaluated by a professional. At Do we need to repair shrinkage cracks in foundation walls or slabs? we discuss how we decide if a foundation crack needs repairing the first place. The diagnosis and evaluation of foundation cracks and structural foundation damage and repair methods are discussed extensively at FOUNDATION REPAIR METHODS

Suggestions for Repairing Concrete Foundation Shrinkage Cracks

Repairs to foundation cracks which are not traced to building movement, structural problems, site problems, or other conditions which require site or structural repairs may be attempted for cracked foundations and other cracked concrete structural elements using a variety of products and materials such as masonry repair epoxy or sealant products.

These products, some of which include even structural repair epoxies, might be used to seal against water leakage as well, and may be used for repairing certain cracks in concrete foundations following evaluation and advice from a foundation professional. An evaluation of the presence, absence, or condition of reinforcing steel in cracked concrete foundations should be a part of such an inspection.

Shrinkage cracks, which are not normally a structural defect in a building, may nonetheless need to be sealed against water entry. Common repair methods include chipping out the crack and applying a masonry patching compound to the surface, use of epoxies, or other sealants.

Water entry leaks at foundation cracks: Polyurethane foam sealant is used for foundation crack repairs to stop water entry. (Also find and correct outside water sources). See our article on Using Polyurethane Foam for Foundation Repairs for details on using this product to seal foundation cracks against leakage.

For various methods and products used to seal cracks in concrete floors or walls, see How to Seal Cracks in Concrete a description of various products and methods used to seal or repair cracks in poured concrete walls, foundations, floors, & slabs.

Once any concrete cracks it is possible for water to leak into the building through the crack. There are several ways to repair a basement crack leak. An easy, quick, and effective measure to stop basement or crawl space water entry through a foundation crack is to perform an injection of polyurethane foam into the basement crack. [Also be sure to find and fix the sources of water outside.]

Water entry leaks at foundation cracks: Polyurethane foam sealant is used for foundation crack repairs to stop water entry. (Also find and correct outside water sources).

Cracks at Control Joints in Concrete explains how we prevent shrinkage cracks in poured concrete floors and walls

Repair Methods for Vertical Foundation Movement - Foundations, slabs, fireplaces, chimneys

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. As movement appeared to be ongoing over more than a year, the builder might have repaired the foundation by supporting it from below using one of the methods listed at Vertical Movement Repairs.

A detailed discussion and illustration of repair methods for foundation settlement or "vertical foundation movement" repair is provided at Vertical Movement Repairs where we explain and illustrate various methods to arrest foundation settlement, and where appropriate, to raise or level or reinforce settling or moving foundation walls or slabs.

Additional details provided at Vertical Movement Repairs include descriptions of grout pumping to stabilize soils or elevate slabs, slab jacking to stabilize or lift settled slabs over deeper unstable soils, the use of driven steel pins to stabilize settling foundation walls or footings, the use of helical piers or "screw piers" such as those provided by A.B. Chance to repair sinking foundations or to level floor slabs, and a similar use of friction piers such as those provided by Magnum piering - are driven piles which rely on soil friction against the sides of the pile. Since it's sometimes the only appropriate repair method for foundation damage, we also illustrate foundation reconstruction.

Repair Methods for Bulged Foundation Walls

Repair methods for bulged foundation walls are illustrated and discussed in detail at Bulged foundation Repairs where we discuss the use of pilasters, reinforcing steel I-beams, foundation anchors, sister walls, steel cables, and even complete foundation wall reconstruction to deal with foundation wall bulging, cracks, leaning, or movement.

Horizontal foundation movement creep

• Steel pins for foundation creep repair or prevention: The wall may be pinned to the surrounding soil or hillside. Pinning moving walls is a separate engineering problem and involves a critical step in discovery of the various components in movement (site drainage, footing condition, condition of underlying soils, clay, or rock.
  
  
• Excavation and reconstruction for foundation creep movement Excavation and reconstruction, possibly with reinforcement over original design and with additional foundation and site drainage is often required.

FOUNDATION INSPECTION STANDARDS - Foundation Inspection Standards - ASHI Standards of Practice (American Society of Home Inspectors)

Notice that in some Standards there was no mention of observations of damage or unsafe conditions!

• This inconsistency in ASHI Standards reflects debate, fear, risk
• Due Diligence: Clients expect inspection to identify concerns & defects
• Engineering and Code Standards: pertain mostly to new construction; engineering analysis of foundation defects and design of repairs is beyond the scope of a professional home inspection and inspector; a home inspector who happens to be qualified to perform such services is not prohibited from doing so on making appropriate arrangements with a client.

But notwithstanding Section 4.1 above, the following section requires the inspector to observe and report evidence of significant damage, including to visible portions of the foundation. Significant in this case means in need of immediate major repair; it might also mean in need of further evaluation by a qualified expert.

2.2 inspectors shall ... 2.2.b.3. ... state ... any ... components

... in need of immediate major repair

2.3 These Standards are not intended to limit inspectors from

2.3.A. reporting observations and conditions in addition

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Technical Reviewers & References

• InspectAPedia.com^® - Daniel Friedman
• InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also list books on the specific article topic as well as other references, and information sources.
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Additional technical contributors & reference sources for this article are listed below.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

FOUNDATION DAMAGE REPORTS
FOUNDATION REPAIR METHODS
  Bulged foundation Repairs
  Crack Repair Methods
  Horizontal Movement Repairs
  Polyurethane Foam Injection
  Shrinkage Crack Repairs
    How to Seal Cracks in Concrete
    Polyurethane Foam Injection
  Vertical Movement Repairs
ADDITIONAL READING
FOUNDATION INSPECTION STANDARDS

• "Concrete Slab Finishes and the Use of the F-number System", Matthew Stuart, P.E., S.E., F.ASCE, online course at www.pdhonline.org/courses/s130/s130.htm
• 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
• A.B. Chance foundation repair systems, helical piers, foundation repairs www.abchance.com
• Dwyer of Florida, supplier of Helical Piles, foundation repair, and concrete restoration in Florida, exclusive dealer for Magnum piering. This company provides helical piles, foundation settlement repair, concrete restoration, shotcrete, pressure grouting, and slabjacking for residential and commercial buildings. 1-866-900-PIER www.dwyerflorida.com
• 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
• Aaron Kuertz aaronk@appliedtechnologies.com, with Applied Technologies regarding polyurethane foam sealant as other foundation crack repair product - 05/30/2007
• 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*
• *These reviewers have not returned comment 6/95

NOTE: Journal of Light Construction articles are available on CD ROM from the Journal of Light Construction, www.bginet.com, 802-434-4747

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building design, inspection, and repair, and about indoor environment testing, diagnosis, and cleanup are at the InspectAPedia Bookstore.
• 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 reprints available from some inspection tool suppliers)
• Design of Wood Structures, Donald E. Breyer, McGraw Hill, 1988 ISBN 0-07-007675-8
• Building Failures, Diagnosis & Avoidance, 2d Ed., W.H. Ransom, E.& F. Spon, New York, 1987 ISBN 0-419-14270-3
• Guide to Domestic Building Surveys, Jack Bower, Butterworth Architecture, London, 1988, ISBN 0-408-50000 X
• ASHI Training Manual - not recommended: incomplete, inaccurate, overpriced--DF
• The Home Reference Book and other Manuals from Carson Dunlop, Home Pro, T.I.E., Inspection Training Associates (Home Inspection training/report firms)
• "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
• InspectAPedia.com - The Free Home Inspection & Construction Diagnosis Public Information Website
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