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STRUCTURAL INSPECTIONS & DEFECTS
AGE of a BUILDING - how to determine
BRICK FOUNDATIONS & WALLS
CHIMNEY INSPECTION DIAGNOSIS REPAIR
COLD POUR JOINTS, CONCRETE
COLUMNS & POSTS, DEFECTS
DISASTER BUILDING INSPECTION & REPAIR
EARTHQUAKE DAMAGED FOUNDATIONS
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOD DAMAGE TO FOUNDATIONS
FOOTING & FOUNDATION DRAINS
FOOTINGS EXPOSED, Repair Methods
FOUNDATION BULGE or LEAN MEASUREMENTS
FOUNDATION CONSTRUCTION TYPES
FOUNDATION CONTRACTORS, ENGINEERS
FOUNDATION CRACKS & DAMAGE GUIDE
FRAMING DAMAGE, INSPECTION, REPAIR
GRADING, DRAINAGE & SITE WORK
GUTTERS & DOWNSPOUTS
INSECT INFESTATION / DAMAGE
MOBILE HOMES, DOUBLEWIDES, TRAILERS
MODULAR HOME CONSTRUCTION
MOISTURE CONTROL in BUILDINGS
RETAINING WALL DESIGNS, TYPES, DAMAGE
RETAINING WALL GUARD RAILINGS
STRAW BALE CONSTRUCTION
STRUCTURAL DAMAGE PROBING
STRUCTURAL WOOD ASSESSMENT
THERMAL EXPANSION of MATERIALS
TIMBER FRAMING, ROT
WATER BARRIERS, EXTERIOR BUILDING
WATER ENTRY in BUILDINGS
WINTERIZE A BUILDING
This article describes how to choose a foundation crack diagnostic engineer or contractor, how to choose a foundation repair expert, and how the expert will evaluate building foundation damage. This article series describes how to evaluate and repair foundation damage. Types of foundation cracks, crack patterns, differences in the meaning of cracks in different foundation materials, site conditions, building history, and other evidence of building movement and damage are described to assist in recognizing foundation defects and to help the inspector separate cosmetic or low-risk conditions from those likely to be important and potentially costly to repair.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Question: I've now asked four foundation contractors and gotten very different opinions
Sketch of differential settlement (below left) is provided courtesy of Carson Dunlop Associates.
I'm going a little nuts here about this foundation crack and would love some guidance. When I bought my 100 year old home in Brooklyn a year ago, the basement side-wall right near the front of the house had a diagonal crack from a window to the corner. it's about 4 feet and starts a little wider and gets smaller. This sidewall is on the detached side of the house.
A few weeks ago, I noticed a new, very thin horizontal crack. After researching it, I realized it goes almost the full length of the house. It wavers up and down a little, but is mostly a little above grade and near the middle of the wall. Next to this wall is an unused driveway (it's actually too small for a car...so it really hasn't been used).
I've now seen 4 contractors and gotten very different opinions.
I'm kinda at my wits end with time and money and appreciate any advice. Best, - BL
Reply: We need to know the type of foundation movement, its cause, and its impact on structure to decide on urgency and type of foundation repair needed
A competent onsite inspection by an expert who is familiar with the causes and cures of foundation damage usually finds additional clues that help accurately diagnose a problem beyond what would occur to a homeowner to describe in email. Put another way, we cannot reliably diagnose the cause, nor evaluate the significance of a crack by email text description, though knowing the type of foundation material, site characteristics, drainage issues, and seeing some photos, measurements, and building history would help. That said, here are some things to consider:
The urgency of foundation repair depends on several factors such as
A foundation expert may also consider:
The foundation materials: what was used. For example, a crack in steel-reinforced poured concrete foundations has different implications from the same crack size, shape, location, pattern in a masonry block foundation. For non-trivial foundation damage, the inspector, engineer, or contractor may want to identify the building foundation construction type, materials, sequence of construction - the history of the site, the foundation itself, and its construction details. See FOUNDATION CONSTRUCTION TYPES.
Site factors affecting the structure such as slope, drainage, rock, or nearby activities such as blasting. See SITE FACTORS AFFECTING FOUNDATIONS.
The construction type, materials, sequence of construction - the history of the site, the foundation, and its construction details. See FOUNDATION CONSTRUCTION TYPES.
First Identify Severe or Dangerous Foundation Damage - collapse risk
Watch out: As we introduce at our home page for this topic, FOUNDATION CRACKS & DAMAGE GUIDE, since certain masonry structure defects, such as even slightly-bulged structural brick masonry walls (above or below ground level - BRICK FOUNDATIONS & WALLS) or severely bulged below-ground masonry block or stone foundations, (BULGED vs. LEANING FOUNDATIONS) can lead to sudden precipitous and catastrophic building collapse, dangerous conditions may be present at some properties.
While there are often hidden conditions which can disguise building conditions, the ability to recognize those potentially urgent or dangerous conditions which can be detected is important in a foundation inspection.
Get the Details that Support the Contractor's Opinion
Watch out also and avoid or at least defer non-urgent repairs that may be unnecessarily costly in comparison with the impact of the crack on the structure or that fail to first identify and understand the cause of the foundation cracking and second to evaluate and understand its impact on the structure.
Some fellows who work in construction are very experienced, knowledgeable, and honest, but they were not English majors in school. You have to ask to hear more of the contractor's reasoning before you'll be comfortable with an answer like "Nah, don't worry about it!" much less "Yeaaah, this is a big problem and needs a big expensive repair."
Make a Thorough and Technically Accurate Foundation Inspection
In addition to the outline of how we approach foundation inspection found (described beginning at FOUNDATION INSPECTION METHODS), here is some basic advice about how to evaluate foundation damage:
If it is not apparent that a major problem exists (see our Watch out: warnings throughout this website) it's ok to start with a contractor. Any building inspector, building contractor, masonry repair contractor, or carpenter needs to be able to recognize when additional expert evaluation or repair is needed by a foundation or structural engineer or foundation repair specialist.
Ask for a Foundation Inspection Report
Evaluate the information which has been collected (history, observations, clues), visual evidence of their impact on the structure, and their importance.
When the foundation expert you are consulting suggests that costly or dangerous conditions exist, it is important that you have an accurate understanding of the problem and that the repair is appropriate. A professional foundation inspector, engineer, architect, or contractor should be able to communicate her/his observations and recommendations to the client with clarity so that the client understands the implications of the findings and the need for action (if any). See FOUNDATION DAMAGE REPORTS for details.
Choose a Qualified Foundation Expert
For costly or potentially dangerous foundation damage, be sure that your "expert" really is one.
A civil engineer or structural engineer who is specifically experienced in building foundation diagnosis and repair can give reliable and often economical advice on what foundation repair is needed. So can some experienced foundation repair contractors.
Foundation Damage Repairs
Depending on the condition of the foundation system, repairs may be needed, and in emergency cases such as the threat of imminent collapse, other measures such as installation of temporary foundation support, or even evacuating an unsafe structure and keeping people away from it could be in order. An example is the discovery of a bulged structural brick wall - a condition that can cause sudden catastrophic building collapse. See FOUNDATION REPAIR METHODS
Watch out for "foundation experts" who don't know foundations: OPINION-DF: even licensed professional engineers or architects who do not have specific experience and training in building foundations. Those experts can often design a repair that will be "safe" and "work" but we have found that some who are not familiar with foundations are not aware of repair products and procedures specifically designed for these problems.
The result can be "overkill" or a foundation repair design that was more complex, more disruptive, and more expensive than necessary. At Vertical Foundation Movement Repairs we mention a case where just this problem occurred at a home built over a landfill.
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