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How to Distinguish Settlement Cracking from Frost Heave in Concrete Foundations, Walls, Floor Slabs
- POST a QUESTION or COMMENT about t how we tell the difference between building settlement & frost heaves
How do we tell the difference between foundation or slab settlement & foundation or slab frost heaves?
This article describes how to distinguish frost heave cracking from settlement cracking in concrete slabs - a division of our article on How to Identify and Evaluate Settlement Cracks in Slabs in Poured Concrete Slabs or in concrete floors in basements, crawl spaces, or garages.
This article series 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.
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Concrete Slab Settlement Cracks Compared with Frost Heaves in Poured Concrete Slabs
Where cracks appear in slabs in homes built in freezing climates, it can be difficult to distinguish between frost heaves and settlement since both types of movement can cause similar cracking in a slab or foundation.
Our photo (left) shows frost-heaved poured concrete, in this case located outdoors. But these conditions can occur indoors too if heat is lost to a building, and especially if there is water, moisture, or a clogged drain line below a basement or floor slab.
We often find frost heaves too at garage floors near the garage door.
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.
Clues suggesting settlement cracks in a concrete slab
- Evidence of probable backfill or infill defects
below a poured concrete slab: significant cracks in a garage floor slab that are not near nor tracking the footing across the garage entry, especially where the level of the garage floor is well above outside grade - fill was needed inside the garage foundation. - Evidence of extensive poured concrete slab settlement
such as noting that the level of the top of the slab is below a concrete trace line along the foundation walls where the top was located when the slab was originally poured is clear evidence of slab settlement. [We regret we have not photographed this condition though it is quite obvious - if any readers have photographed this condition please let us know.]
Clues suggesting frost heaved cracks in a concrete slab
Frost heave cracking is likely to be cyclical unless the building has gone through less than one cycle of seasons. Frost heave cracking can often be reasonably postulated as a cause or main factor in slab cracking if the inspector can identify site conditions that make it likely that there has been water around and under the foundation or slab, and that freezing conditions have occurred.
- Evidence of cyclical movement in poured concrete foundations and slabs such as crumbling broken edges of cracked sections may suggest recurrent movement.
- Evidence of a history of site or building water entry or poor site drainage may suggest (in areas of freezing climates) frost heaved damage to a poured concrete floor slab.
- Absence of evidence of backfill or site fill problems at a poured concrete structure: a garage slab poured at grade and cracked across its width near the entry is more likely due to frost heaves. But remember this basic principle of diagnostics: absence of evidence is not evidence of absence. It may be inconclusive.
Photos of Frost Heave Cracked Basement Slabs in Older Homes
A classic example of slab cracking due to frost heaving can be seen in some older homes (1885-1935) in which roof drainage was routed
from gutters down into the home to a drain that ran under the basement floor slab and thence out to
a storm drain in the street (urban houses).
Our photo (left) shows a frost heaved and cracked basement floor slab in a New York Home. A combination of loss of heat and lots of water below the slab caused the cracking around the Lally column and in other basement locations.
In this case the floor (and the Lally column that was sitting on the concrete floor, not on its own independent pier) heaved upwards.
Watch out: you might see similar crack patterns around a Lally column that is settling due to a missing or inadequate pier. It's simple: is the floor heaved upwards (convex) or has it settled (concave). Or is it cyclical, heaving up and down as water levels and winter temperatures vary?
In such homes you may find that the basement floor slab is seriously broken up and heaved, some sections pushed several inches into the air, along either side of a rather straight line which tracks exactly the route of one of these buried drains.
[We regret we didn't take photos of this - if any readers have photographed this condition please let us know.]
...
Continue reading at SETTLEMENT vs. SHRINKAGE CRACKS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see these
Concrete Crack Diagnosis & Repair Articles
- CONCRETE COLD POUR JOINTS
- CONCRETE CORROSION DUE TO HYDROGEN SULFIDE
- CONCRETE DECK PIER PROCEDURE
- CONCRETE DIY SMALL JOB PROCEDURE
- CONCRETE DELIVERY & MIXING
- CONCRETE FOUNDATION, WALL, SLAB DEFECTS
- CONCRETE REINFORCEMENT, FIBER
- CONCRETE SHRINKAGE CRACKS
- CONCRETE SHRINKAGE CRACK REPAIR
- CONCRETE STAINS: ID & REMOVAL
- CONCRETE SLAB CRACK EVALUATION
- CONTROL JOINT CRACKS in CONCRETE
- FREEZING & WATER DAMAGED SLABS
- FROST HEAVE / EXPANSIVE SOIL CRACKS in SLABS
- SETTLEMENT CRACKS in SLABS
- SETTLEMENT vs. FROST HEAVE CRACKS
- SETTLEMENT vs. SHRINKAGE CRACKS
- SHRINKAGE CRACKS in SLABS
- SHRINKAGE CRACKS at FOUNDATION WALLS
- TEMPERATURE EFFECT on CONCRETE POUR
- CONCRETE SLAB CRACK REPAIR
- FOUNDATION DAMAGE by MATERIAL or INCLUSIONS
Suggested citation for this web page
SETTLEMENT vs. FROST HEAVE CRACKS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
Or see this
INDEX to RELATED ARTICLES: ARTICLE INDEX to BUILDING STRUCTURES
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Citations & References
In addition to any citations in the article above, a full list is available on request.
- "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
- "Best Practices for Concrete Sidewalk Construction," Balvant rajani, Canadian National Research Council
- "Design Considerations for Perlite Roof Slabs," a chapter in "Perlite Concrete Grade for Lightweight Concrete Construction", United Perlite Corporation
- 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
- Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
- 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.
- Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
- 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.
- Appliances and Home Electronics, - energy savings, U.S. Department of Energy
- Avongard FOUNDATION CRACK PROGRESS CHART [PDF] - structural crack monitoring
- BASEMENT MOISTURE CONTROL [PDF] U.S. Department of Energy
- Building Failures, Diagnosis & Avoidance, 2d Ed., W.H. Ransom, E.& F. Spon, New York, 1987 ISBN 0-419-14270-3
- 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
- The Circular Staircase, Mary Roberts Rinehart
- Construction Drawings and Details, Rosemary Kilmer
- CRAWL SPACE MOISTURE CONTROL [PDF] U.S. Department of Energy
- 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. - 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.
- 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
- Historic Preservation Technology: A Primer, Robert A. Young, Wiley (March 21, 2008) ISBN-10: 0471788368 ISBN-13: 978-0471788362
- LOG HOMES: MINIMIZING AIR LEAKAGE [PDF] U.S. Department of Energy
- Manual for the Inspection of Residential Wood Decks and Balconies, by Cheryl Anderson, Frank Woeste (Forest Products Society), & Joseph Loferski, October 2003, ISBN-13: 978-1892529343,
- Masonry structures: The Masonry House, Home Inspection of a Masonry Building & Systems, Stephen Showalter (director, actor), DVD, Quoting:
Movie Guide Experienced home inspectors and new home inspectors alike are sure to learn invaluable tips in this release designed to take viewers step-by-step through the home inspection process. In addition to being the former president of the National Association of Home Inspectors (NAHI), a longstanding member of the NAHI, the American Society of Home Inspectors (ASHI), and the Environmental Standard Organization (IESO), host Stephen Showalter has performed over 8000 building inspections - including environmental assessments. Now, the founder of a national home inspection school and inspection training curriculum shares his extensive experience in the inspection industry with everyday viewers looking to learn more about the process of evaluating homes. Topics covered in this release include: evaluation of masonry walls; detection of spalling from rebar failure; inspection of air conditioning systems; grounds and landscaping; electric systems and panel; plumbing supply and distribution; plumbing fixtures; electric furnaces; appliances; evaluation of electric water heaters; and safety techniques. Jason Buchanan --Jason Buchanan, All Movie Review - Masonry Design for Engineers and Architects, M. Hatzinikolas, Y. Korany, Canadian Masonry (2005), ISBN-10: 0978006100, ISBN-13: 978-0978006105
- Masonry Structures: Behavior and Design, Robert G. Drysdale, Ahmid A. Hamid, Lawrie R. Baker, The Masonry Society; 2nd edition (1999), ISBN-10: 1929081014, ISBN-13: 978-1929081011
- Masonry, Engineered: Using the Canadian Code, J. I. Gainville, Cantext publications (1983), ASIN: B0007C37PG
- Masonry, Non-reinforced masonry design tables, Hans J. Schultz, National Concrete Producers Association and the Canadian Masonry Contractors Association (1976), ASIN: B0007C2LQM
- MOISTURE CONTROL in BUILDINGS [PDF] U.S. Department of Energy
- MOISTURE CONTROL in WALLS [PDF] U.S. Department of Energy
- 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
- 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. - VAPOR BARRIERS or VAPOR DIFFUSION RETARDERS [PDF] U.S. DOE - how vapor barriers work, types of vapor diffusion barriers, installing vapor barrier
- VENTILATION for ENERGY-EFFICIENT BUILDINGS [PDF] Purpose of ventilation, ventilateion strategies, etc.
- In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
CONTINUE READING or RECOMMENDED ARTICLES.
Sinkholes and Sudden Land Subsidence References, Products, Consultants
- "A Hole in the Ground Erupts, to Estonia's Delight", New York Times, 9 December 2008 p. 10.
- History of water usage in Estonia: (5.7 MB PDF) jaagupi.parnu.ee/freshwater/doc/the_history_of_water_usage_systems_in_estonia.pdf
- "Quebec Family Dies as Home Vanishes Into Crater, in Reminder of Hidden Menace", Ian Austen, New York Times, 13 May 2010 p. A8. See http://www.nytimes.com/
- "Quick Clay", Wikipedia search 5/13/2010 - http://en.wikipedia.org/wiki/Quick_clay
- Florida DEP - Department of Environmental Protection, & Florida Geological survey (http://www.dep.state.fl.us/geology/default.htm) on Florida sinkholes: Effects of Sinkholes on Water Conditions Hernando County, Florida, Brett Buff, GIS in Water Resources, 2008, Dr. David R. Maidment, Photos - Tom Scott, Florida Geographic Survey - Web Search 06/09/2010 - http://www.dep.state.fl.us/geology/geologictopics/jacksonsink.htm
and - http://www.dep.state.fl.us/geology/geologictopics/sinkhole.htm
also see
Lane, Ed, 1986, Karst in Florida: Florida Geological Survey Special Publication 29, 100 p. - Foundation Engineering Problems and Hazards in Karst Terranes, James P. Reger, Maryland Geological Survey, web search 06/05/2010, original source: http://www.mgs.md.gov/esic/fs/fs11.html
Maryland Geological Survey, 2300 St. Paul Street, Baltimore, MD 21218 - "Frost Heaving Forces in Leda Clay", Penner, E., Division of Building Research, National Research Council of Canada, Canadian Geotechnical Journal, NRC Research Press, 1970-2, Vol 7, No 1, PP 8-16, National Research Council of Canada, Accession number 1970-023601, Quoting from original source
The frost heaving forces developed under a 1 ft. (30.5 cm) diameter steel plate were measured in the field throughout one winter. The steel plate was fixed at the ground surface with a rock-anchored reaction frame. heave gauges and thermocouples were installed at various depths to determine the position and temperature of the active heaving zone. The general trend was for the surface force to increase as the winter progressed. when the frost line approached the maximum depth the force was in excess of 30,000 lb (13,608 KG). Estimates of the heaving pressure at the frost line ranged from 7 to 12 psi (0.49 to 0.84 KG/cm) square during this period. The variation of surface heaving force was closely associated with weather conditions. Warming trends resulting in a temperature increase of the frozen layer caused the forces to decline.
- "Geoscape Ottowa-Gatineau Landslides", Canada Department of Natural Resources, original source http://geoscape.nrcan.gc.ca/ottawa/landslides_e.php - quoting from that source:
Leda clay slopes in the Ottawa valley are vulnerable to catastrophic landslides. More than 250 landslides, historical and ancient, large and small, have been identified within 60 km of Ottawa. Some of these landslides caused deaths, injuries, and property damage, and their impact extended far beyond the site of the original failure. In spectacular flowslides, the sediment underlying large areas of flat land adjacent to unstable slopes liquefies. The debris may flow up to several kilometres, damming rivers and causing flooding, siltation, and water-quality problems or damaging infrastructure. Geologists and geotechnical engineers can identify potential landslide areas, and appropriate land-use zoning and protective engineering works can reduce the risk to property and people.
Deposits of Leda clay, a potentially unstable material, underlie extensive areas of the Ottawa-Gatineau region. Leda clay is composed of clay- and silt-sized particles of bedrock that were finely ground by glaciers and washed into the Champlain Sea. As the particles settled through the salty water, they were attracted to one another and formed loose clusters that fell to the seafloor. The resulting sediment had a loose but strong framework that was capable of retaining a large amount of water. Following the retreat of the sea, the salts that originally contributed to the bonding of the particles were slowly removed (leached) by fresh water filtering through the ground. If sufficiently disturbed, the leached Leda clay, a weak but water-rich sediment, may liquefy and become a 'quick clay'. Trigger disturbances include river erosion, increases in pore-water pressure (especially during periods of high rainfall or rapid snowmelt), earthquakes, and human activities such as excavation and construction.
After an initial failure removes the stiffer, weathered crust, the sensitive clay liquefies and collapses, flowing away from the scar. Failures continue in a domino-like fashion, rapidly eating back into the flat land lying behind the failed slope. The flowing mud may raft intact pieces of the stiffer surface material for great distances.
- Kochanov, W. E., 1999, Sinkholes in Pennsylvania: Pennsylvania
Geological Survey, 4th ser., Educational Series 11, 33 p., 3rd printing April 2005, Pennsylvania Department of Conservation and Natural Resources / Bureau of Topographic and Geologic Survey, DCNR Educational Series 11, Pennsylvania Geological Survey, Fourth Series, Harrisburg,
1999 - web search 06/05/2010, original source: http://www.dcnr.state.pa.us/topogeo/hazards/es11.pdf - Quoting from the document introduction:
The first 18 pages of this booklet contain an explanation of how sinkholes develop. In order to tell the sinkhole story, it is important to discuss a number of related geologic disciplines. The words used to describe sinkholes and these disciplines may be a bit unfamiliar. However, general explanations are given throughout the booklet to help clarify their meanings. Key words are printed in bold type for emphasis. The more important ones are defined in a Glossary that begins on page 29. The remaining sections, starting with “Sinkholes in the Urban Environment” (page 18), deal with sinkholes and their impact on our environment. This includes recognition of subsidence features and sinkhole repair. - [1] Sarah Cervone, [web page] data from the APIRS database, Graphics by Ann Murray, Sara Reinhart and Vic Ramey, Vic Ramey is the editor. DEP review by Jeff Schardt and Judy Ludlow. The web page is a collaboration of the Center for Aquatic and Invasive Plants, University of Florida, and the Bureau of Invasive Plant Management, Florida Department of Environmental Protection contact: varamey@nersp.nerdc.ufl.edu [A primary resource for this article
- [2] Center for Cave and Karst Studies or the Kentucky Climate Center, both at Western Kentucky University
- Vanity Fair - web search 06/04/2010 http://www.vanityfair.com/online/daily/2010/06/what-caused-the-guatemala-sinkhole-and-why-is-it-so-round.html
- Sinkholes, Virginia Division of Mineral Resources,
- Virginia Department of Mines, Minerals and Energy, www.dmme.virginia.gov Virginia Department of Mines, Minerals and Energy Division of Mineral Resources 900 Natural Resources Drive, Suite 500 Charlottesville, VA 22903 Sales Office: (434) 951-6341 FAX : (434) 951-6365 Geologic Information: (434) 951-6342 http://www.dmme.virginia.gov/ divisionmineralresources.shtml - Web search 06/09/2010
Sink Hole & Related Engineering References
- Newton, J. G., 1987, Development of sinkholes resulting from man's activities in the eastern United States: US Geological Survey Circular 968, 54 p.
- Sinclair, W. C., 1982, Sinkhole development resulting from ground-water withdrawal in the Tampa Area, Florida: U.S. Geological Survey Water-Resources Investigations 81-50, 19 p.
- White, W. B., 1988, Geomorphology and Hydrology of Karst Terrains: Oxford University Press, New York, 464 p.
- Williams, J. H. and Vineyard, J. D., 1976, Geologic indicators of subsidence and collapse in karst terrain in Missouri: Presentation at the 55th Annual Meeting, Transportation Research Board, Washington, D.C.
- Barry F. Beck, A. J. (1999). Hydrogeology and Engineering Geology of Sinkholes and Karst. Rotterdam, Netherlands: A. A. Balkema.
- Beck, B. F. (2003). Sinkholes and the Engineering and Environmental Impacts of Karst. Huntsville, Alabama: The American Society of Civil Engineers.
- Beck, B. F. (2005). Sinkholes and the Engineering and Envrionmental Impacts of Karst. San Antonio, Texas: The American Society of Civil Engineers.
- Tony Waltham, F. B. (2005). Sinkholes and Subsidence, Karst and Cavernous Rocks in Engineering and Construction. Chichester, United Kingdom: Praxis Publishing.
- Whitman D., G. T. (1999). Spatial Interrelationships Between Lake Elevations, Water Tables, and Sinkhole Occurence in Central Florida: A GIS Approach. Photogrammetric Engineering and Remote Sensing , 1169-1178.
- Cited References from this article:
- #3. Detecting Sinkholes with Geophysics, Enviroscan, Inc., Lancaster PA 717-396-8922 email@enviroscan.com www.enviroscan.com 2003
- Sinkholes in Guatemala, Guatemala City, Wikipedia - web search 06/04/2010 - http://en.wikipedia.org/wiki/Guatemala_City
- In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
CONTINUE READING or RECOMMENDED ARTICLES.
- Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The HOME REFERENCE BOOK - the Encyclopedia of Homes and to use illustrations from The ILLUSTRATED HOME .
Carson Dunlop Associates provides extensive home inspection education and report writing material. In gratitude we provide links to tsome Carson Dunlop Associates products and services.
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