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This chapter of the "Foundation Crack Bible" discusses in detail the recognition of different types and causes of building foundation movement and foundation damage. We distinguish among vertical movement, horizontal movement, leaning, tipping, bending, differential and uniform settlement, earthquake and storm damage, and other foundation damage patterns.

Our "Foundation Crack Bible" document, of which this web page is a chapter, describes how to recognize and diagnose various types of foundation failure or damage, such as foundation cracks, masonry foundation crack patterns, and moving, leaning, bulging, or bowing building foundation walls.

See FOUNDATION CRACK EVALUATION for a discussion of the diagnosis of specific crack patterns in masonry foundations, and see FOUNDATION BULGE or LEAN MEASUREMENTS which explains a simple method for determining how much bulge or lean is present in a foundation or wall, then see FOUNDATION MOVEMENT ACTIVE vs. STATIC which helps determine if the foundation movement is ongoing, and see FOUNDATION DAMAGE SEVERITY for a discussion of just how much foundation movement is likely to be a concern. At BUCKLED FOUNDATIONS due to INSULATION? we discuss the causes of foundation damage in areas of freezing, wet soils, and clay soils, as well as offering suggestions to avoid foundation collapse from these forces.

To be used properly, this information must be combined with specific on-site observations at the particular building in order to form a reliable opinion about the condition of that building's foundation. Anyone having concern regarding the structural stability, safety, or damage of a building, foundation or other components, should consult a qualified expert. Photographs of types of foundation cracks and other foundation damage: we have a large library of photographs which we're in process of adding to this document. Pending completion of that work, contact the author if assistance is required.

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

Detailed articles on types of foundation movement are listed just below. The sketch is courtesy Carson Dunlop.

FAILURES by FOUNDATION MOVEMENT TYPE   BUCKLED FOUNDATIONS due to INSULATION?   BULGED vs. LEANING FOUNDATIONS   COMBINATIONS OF FOUNDATION MOVEMENT     Bulge & step cracks     Earthquake Damage to Foundations     Flood Damage to Foundations     Foundation Movement During Collapse     Other Foundation Step cracks   HORIZONTAL MOVEMENT IN FOUNDATIONS     Bulging, Leaning & Sliding Wall     Horizontal Foundation Creep     Horizontal Movement & step cracks in brick     Impact Damage to Foundations     Thermal Expansion Cracking in Brick

 VERTICAL MOVEMENT IN FOUNDATIONS
    Diagonal Cracks in Concrete Foundations
    Diagonal Step Cracking in Masonry
    Differential vs. Uniform Settlement Cracks
    Leaning or Tipping Buildings
    Uniform Width vs. Tapered Foundation Cracks
    Vertical Cracks

Vertical Movement in Foundations & Walls

Vertical movement in foundations, in the most general cases, is caused by downwards movement of the wall or wall footings such as when a wall footing sinks in soft soil, or by an up and down movement of the wall or wall footings such as when a wall is disturbed by frost in a freezing climate or by expansive clay soils which expand or shrink as their water content increases or decreases.

We discuss types of vertical foundation movement in detail at VERTICAL MOVEMENT IN FOUNDATIONS. Here are some classes of vertical foundation or building wall movement which we illustrate and discuss in more detail below:

• Differential foundation settlement: one portion of a building foundation or wall moves up or down separately from its neighbor. See Differential vs. Uniform Settlement Cracks. Differential settlement will damage the foundation or wall by producing (usually vertical, possibly diagonal or stair stepped) cracks and other symptoms of wall movement. The large foundation crack in this poured concrete wall was caused by differential settlement in a new foundation wall. All of this movement occurred during the first 13 months after the home was built.
• Uniform building settlement: an entire building moves up or down together, causing little or no foundation cracking or damage, though there could be important damage to mechanical connections to the building and even dangerous gas line leaks.
• Building tipping or leaning: an entire building tips or leans out of level. For a detailed discussion of the diagnosis of specific crack patterns caused by wall bulging and leaning in masonry foundations, and see FOUNDATION BULGE or LEAN MEASUREMENTS
• Vertical shrinkage cracks in foundation walls: If a vertical crack is fairly uniform in width we pose that it was produced either by a non-sloping vertical settlement of one section of the footing or foundation wall, or the crack was produced by shrinkage (in some wall materials like concrete) not by vertical movement at all. We discuss the types of crack or movement patterns produced by shrinkage, expansion, and settlement further at SHRINKAGE vs EXPANSION vs SETTLEMENT.
• Earthquake or Storm Damage to Buildings: can cause complex building movement in multiple directions, as we illustrate at Foundation Movement due to Earthquake.

Horizontal Movement in Foundations & Masonry Building Walls

Horizontal movement in building foundations or walls is generally caused by an external lateral or "sideways" force applied to some portion of the wall. Depending on the construction materials used and the strength of a foundation wall, a force applied to the wall can cause it to move in any of several ways which we discuss in detail at HORIZONTAL MOVEMENT IN FOUNDATIONS.

• Bulging foundation wall movement: the wall may bend or "bulge", tending to bulge away from the force (usually inwards into the building from earth, water, or frost pressure), with the greatest amount of inwards movement at or near the point of greatest pressure or force being applied.
• Leaning foundation wall movement: the wall may lean away from the force being applied (usually into the building from the same forces listed above).
• Shifting or creeping foundation wall movement: a foundation wall, or portions of it, may remain close to vertical, without leaning or bulging, but forces applied to the wall may cause the entire wall (or a portion of it) to move horizontally. We see horizontal shift or creep occurring in several cases:
• Complex foundation wall movement: most of the drawings we see at seminars on foundation damage or used by companies offering foundation repair products are clear and helpful for understanding the concept of foundation damage and movement, but often they do not describe what we actually find in the field.

Combinations of Foundation Wall Movement, Horizontal & Vertical Crack Patterns Occurring Together

We discuss the inspection and analysis of foundation damage which shows a combination of different movement directions, forces, or crack patterns in detail at COMBINATIONS OF FOUNDATION MOVEMENT including the following examples of combination foundation damage:

• Step cracks combined with bulging walls
• Combinations of foundation wall movement during foundation collapse
• Combinations of foundation wall movement due to earthquake, flood, impact, or explosion
• Step cracks combined with leaning foundation walls

How to distinguish between a "bulged" foundation wall and a "leaning" foundation wall, and why we care

Understanding the location and pattern of foundation wall cracking or movement may help us diagnose its cause and thus may help us understand what actions are needed to stop further foundation movement. We discuss how and why we make this distinction between bulging and leaning foundations in detail at BULGED vs. LEANING FOUNDATIONS.

Even a concrete wall which is bulged is likely to be cracked horizontally, though perhaps not in such a straight line.

But a bulged reinforced concrete wall would be very rare unless perhaps the concrete wall bulged, or its forms bulged, during the time that the concrete was being poured and was still wet. It's more likely that a reinforced concrete wall will be caused to lean or to shift horizontally while a masonry unit wall or stone wall is likely to be bulged and cracked by the same external forces.

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FOUNDATION CRACKS & DAMAGE GUIDE - how to inspect and diagnose foundation problems, in-depth diagnosis, and evaluation of all types of structural and non-structural cracks in residential foundations [Brick, Concrete, Masonry Block, Stone]
EARTHQUAKE DAMAGED FOUNDATIONS - examples of earthquake-damaged building foundations
FOUNDATION CONSTRUCTION TYPES - identify different foundation types, construction materials, effects of sequence of construction
FOUNDATION INSPECTION METHODS - what to look for when inspecting any building foundation
FAILURES by FOUNDATION TYPE & MATERIAL- unique failure characteristics of each foundation material
  Block Foundation & Wall Defects
  Brick Foundation & Wall Defects
  Brick Thermal Expansion Cracking
  Concrete Poured Foundation Wall & Slab Defects
  Concrete Pre-cast Foundation Defects
  Stone Foundation Defects
  Wood Foundation Defects
FAILURES by FOUNDATION MOVEMENT TYPE -recognize & diagnose types of foundation damage by the nature of foundation movement
  BULGED vs. LEANING FOUNDATIONS - distinction of foundation bulging from foundation leaning has important implications for stability
  COMBINATIONS OF FOUNDATION MOVEMENT - the real world of foundation cracks and movement: often more than one force is at work
    Bulge & step cracks
    Earthquake Damage to Foundations
    Flood Damage to Foundations
    Foundation Movement During Collapse
    Other Foundation Step cracks
  HORIZONTAL MOVEMENT IN FOUNDATIONS - detection, causes, effects, evaluation of horizontal or lateral foundation movement; hillsides
    Bulging, Leaning & Sliding Wall
    Horizontal Foundation Creep
    Horizontal Movement & step cracks in brick
    Impact Damage to Foundations
    Thermal Expansion Cracking in Brick
  VERTICAL MOVEMENT IN FOUNDATIONS - detection, causes, effects, evaluation of vertical foundation movement, differential settlement
    Diagonal Cracks in Concrete Foundations
    Diagonal Step Cracking in Masonry
    Differential vs. Uniform Settlement Cracks
    Leaning or Tipping Buildings
    Uniform Width vs. Tapered Foundation Cracks
    Vertical Cracks
FLOOD DAMAGE TO FOUNDATIONS - examples of flood damaged foundations, flood damage case analysis: were these cracks due to flooding?
FOUNDATION DEFECTS OF OMISSION - recognize things that were left out, like footings, reinforcement, soil compaction, during foundation construction
FOUNDATION CRACK EVALUATION- recognize & diagnose types of foundation cracks, movement, damage, by the size, shape, location, pattern of cracks
  DIAGONAL FOUNDATION CRACKS - causes and significance of diagonal foundation cracks, varies by foundation type & material
  HORIZONTAL FOUNDATION CRACKS - causes and significance of horizontal foundation cracks, varies by foundation type & material
  SHRINKAGE vs EXPANSION vs SETTLEMENT - which foundation materials shrink, which expand, & their characteristic crack patterns
  Sinkholes & Building Damage - sinkhole recognition, significance, cause, underlying geology, areas where sinkholes are worst
  VERTICAL FOUNDATION CRACKS - - causes and significance of vertical foundation cracks, varies by foundation type & material
FOUNDATION BULGE or LEAN MEASUREMENTS - procedure for documenting the amount of lean or bulge in a foundation or other building wall
FOUNDATION DAMAGE SEVERITY - rules of thumb for deciding how much foundation movement requires further action
FOUNDATION DAMAGE REPORTS - how to report foundation inspection results and damage
FOUNDATION INSPECTION STANDARDS - definition of scope of what a foundation inspector
FOUNDATION MOVEMENT ACTIVE vs. STATIC - determine if foundation movement was a one-time event or an ongoing problem
FOUNDATION REPAIR METHODS - catalog of methods used to repair damaged foundations and masonry building walls
  Bulged foundation Repairs
  Crack Repair Methods
  Horizontal Movement Repairs
  Shrinkage Crack Repairs
  Vertical Movement Repairs
SITE FACTORS AFFECTING FOUNDATIONS - drainage, rock, soil compaction, slope or grading, bedrock, sloping bedrock, proximity to roads
SLAB CRACK EVALUATION - recognize and diagnose different types of slab or concrete floor cracks and movement
  Control Joint Cracks in Concrete - what are control joints, why they are needed, what happens when they're omitted; are they structural?
  Freezing & Water Damage - recognize frost and water damage to concrete slabs, distinguish from other crack types
  Frost Heave/Expansive Soil Cracks in Slabs - distinguish between frost damage and expansive clay soil damage to slabs
  Seal Cracks by Polyurethane Foam Injection - stop basement or crawl space leakage
  Seal Cracks in Concrete, How To - products and methods used to seal or repair cracks in poured concrete walls, foundations, floors, & slabs.
  Settlement Cracks in Slabs - recognize slab settlement, assess risk, assess potential impact on structure
  Settlement Cracks vs. Frost Heaves - how to tell the difference between frost heaves and foundation settlement; does it matter?
  Settlement Cracks vs. Shrinkage Cracks - critical identification of shrinkage cracks (non-structural) compared with foundation movement
  Shrinkage Cracks in Slabs - causes, prevention, assessment of concrete slab shrinkage cracks
  Shrinkage Cracks Along Foundation Walls - why do we see a gap between a poured concrete slab and its abutting foundation wall?
  Standards for Repair of Cracks in Floors - when does a floor or slab crack need to be repaired? why?
WATER ENTRY in BUILDINGS
  SUMP PUMPS GUIDE - how a sump pump can avoid foundation damage and reduce building water entry
ADDITIONAL READING

• "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.
• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• 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

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