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This article explains how to notice defective, damaged, improperly supported, or missing structural columns, and other structural column & pier mistakes. Our page top photo shows a telepost used as a "permanent" supporting column. Most models of teleposts or "jackposts" are thin-walled steel and are not designed for permanent use. And all columns require proper bearing support at both the column top and bottom. This leaning, cockeyed jackpost is a structural collapse waiting to happen. Detecting omissions, such as leaving out a column or it's pier or footing is an important step in learning 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. Also see FOUNDATION DEFECTS OF OMISSION - MISSING Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman. Structural Columns in Residential Buildings: Visual Inspection for Defects
Some of these are dangerous and risk collapse. But do not fail to pay careful attention to the structural connections themselves: connections between posts and beams, posts and piers, beams and the floors or ceilings they support. Connection failure is often the weak link in residential structural movement and collapse. See DECK COLLAPSE Case Study for an example. FYI we call a 6-inch concrete filled steel column a Lally column after its inventor. Some folks call these just steel columns, or lolly columns or steel posts. Proper Use Compared with Misapplication of Temporary Teleposts or Jackposts in StructuresOur photos below show a proper use of a temporary column, telepost, or jackpost - that gray screw-jack to the right of the white-painted steel column I am touching. The second photo at right shows why the temporary column was put in place: the hollow steel column supporting this beam had rusted through at its base, risking collapse. The collapse of a structural steel column is increased if the column is hollow, rather than concrete-filled.
Thin-walled Steel Teleposts - Maybe Not the Best Choice for Permanent Repairs
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 However what you see is a temporary repair. The rusted steel column should be replaced with a structural column such as a concrete filled steel Lally column that is rated for permanent use. Our photo (left) shows a thin-walled adjustable column in use in a wet crawl area. The repair contractor installed gravel and then plastic to keep moisture levels down in the crawl space. (The post is probably not out of plumb, that was a tilt in the camera when I shot this photo.) But notice that the column extends down through the gravel into the presumably wet surface beneath. Consider that the end of the column is now hidden from view in gravel, that we think this is a recurrent wet area, we can't see if it's wet or not, and more, because this is a tight crawl space, people won't enter it very often to inspect conditions there. A more durable repair would have been a Lally column. Some builders even prefer to use a pressure treated wood 4x4 post in this sort of location, arguing that it is "rustproof". |
Some Teleposts May be Permitted for Permanent Installation
Shown below, some adjustable screw jacks or teleposts such as some Read-I-Post columns are constructed of a heavier-gauge steel and in some jurisdictions they may be approved for permanent use in structures. Often where an adjustable column is permitted for permanent structural use, once it has been properly adjusted in height, its adjusting rod is removed and the screw is tack-welded in place.
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Notice that the installer took care to bolt the Red-I-Post top plate to the beam underside. Let's hope that the beam itself is secured to the floor joists overhead and is protected against lateral movement.
Improper Column Top or Bottom Support, Bearing, or Connections
See our page top photo for an example of a horrible installation of a jackpost that is likely to collapse. Below are more examples of improper telepost installations. At below left we have inadequate bearing surface and no connection between the steel bearing plate and the joist underside. It looks as if the post may also be out of plumb. Boing!
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Which End Goes Up When Installing Screw Jacks & Teleposts?
Our second dangerous telepost photo at above right you can see that the post top screw has bent the steel plate as it pushed into the beam, and the whole assembly is slipping off of the beam and moving to the right. Some installers place screw jacks or teleposts with the screw down against the concrete floor or pier top.
That allows the larger-diameter post "bottom" to be placed up against a steel plate and against the underside of the beam. This "upside down" installation reduces the chances of bending the steel supporting plate and it also places the thick steel screw down on the (often wet) basement or crawl space floor. The thicker steel screw is slower to rust through to the point of collapse than is the thin-walled hollow steel pipe that forms the body of most teleposts.
Supporting Column Location
 It seems obvious that in addition to spacing requirements for supporting steel columns below beams (typicallyi a steel column is placed every eight feet on center in a wood frame two story residential structure), you would also place the column below any splices in the beam. But a splice in a structural beam also needs resistance to bending upwards. Look closely (click any of our images to see a larger view) and you'll see some nice wood putty in that opening splice joint. The splice shown in our photo of a home in Portland ME would probably not have bent if it had been located below that floor joist to the right, and had the supporting column placed below the splice as well as below the josits. |
Improper Structural Columns Failed at 1994 Northridge Meadows Earthquake
As we also discuss at Earthquake Damage to Foundations, defective supporting columns failed at Northridge Meadows during that 1994 earthquake. It appears that hollow 6" pipes were substituted for concrete filled steel Lally columns under part of the building. Once the fireproofing wrap was installed it was not possible to spot this shortcut by visual inspection. The hollow columns failed, permitting the upper floors of the structure to collapse. There were fatalities.
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Here are examples of types of omission that contributed to a structural collapse. During our work at the Northridge Earthquake site in California in 1994 we noticed that some of the supporting Lally columns were hollow rather than concrete filled.
Perhaps due to material shortages or rush during construction, these hollow, and weaker supporting columns were wrapped with a fire-barrier just as were the "real" supporting columns used elsewhere. Our photos show a section of Northridge Meadows which collapsed during the earthquake. At left you can see that this column was hollow. Our opinion was that these were defective columns and that they were a factor in the structural collapse during the Northridge earthquake. Other areas of the same complex moved, columns even leaned, but they did not collapse where the columns were of the proper type and were properly connected to the structure. Other factors in the collapse appeared to include how exterior sheathing had been nailed across or not across certain sections of the building supporting walls. Our list of examples of defects of omission during foundation construction continues below. |
Missing Structural Columns
"Missing" column footings may or may not be a defect depending on design and soil conditions. In some jurisdictions, a poured concrete floor slab may be considered of sufficient thickness and strength to support the column.
Completely missing structural columns such as a basement Lally column, where an owner has removed the column to open up a basement space being remodeled for use as living area. Our photo (left), illustrates one way you can spot a missing column: a Lally column top plate remains tacked in place on the under-side of a built-up beam in a basement. |
How can we take a photo of a missing structural post or column?
 Sometimes you can spot the imprint of this Lally column top plate as a rectangular impression on the underside of a beam even though the steel plate itself was removed. See our photo (left) where you can spot the rectangular imprint of a typical steel Lally column top plate and even two nail holes where the plate had been tacked to the beam underside. And notice that there is a long span, perhaps sixteen feet, with no supporting post. Perhaps the center girder has been boxed in or covered with paneling and corner molding. Ask yourself: when this house was built, given that typically I see a Lally column every 8-feet, I wonder if there was one in the center of this room. Was it removed? Was the center girder reinforced with steel? Is there sagging in the floor above? |
Pipes are Not Structural Column s
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Our photo (left) shows a basement girder supported by cute little 2-inch pipes. We think the installer knew these were not structural-components, because s/he installed these toy "faux-structural" pipes on 5-foot centers. |
Settling or Missing Column Footings & Piers Show up As Cracks, Sags, Movement
Failure to compact the soil under a column pier or footing or under a poured concrete slab which has been placed on backfill can result in column settlement.
Our client is pointing to a supporting column in a location where we suspect that crack pattern around the column, combined with a slight but observable depression at the column base area suggests its pier may be settling.
 
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When we see a column whose base penetrates the concrete floor slab we know the floor was poured around the column - the column was put in place first. We can't see if a proper pier was installed to support the column base - as is usually the case. Perhaps in the installation we show here, the builder set a 4-inch solid concrete block on (poorly-compacted) fill inside the building foundation, set his post on that, and jacked away. When the fill settles the block settles too, and the column may move downwards, cracking the concrete floor around its base in the pattern we show here.
- Omitted steel reinforcement - footings missing re-bar or other required steel rods (not visibly detectable after construction) may show up as breaks or cracks and settlement around a post that rests just on the floor slab
- Missing piers beneath interior or exterior posts may be visible as post settlement or movement downwards through the floor slab without cracks in the slab itself.
How to Evaluate Rusting Steel Structural Columns & Posts That Can Risk Building Collapse
As we also discussed at BASEMENT LEAKS, INSPECT FOR, even a concrete filled steel Lally column can deteriorate enough to lead to building movement or instability. But hollow steel columns such as teleposts and even steel pipes people sometimes think will support a building, heavy exfoliating rust on the columns can lead to crushing or splitting and a structural collapse.
When evaluating the history of water entry in a building we like to look at structural components that have been in place since the building was completed - those are parts that will have been exposed to flooding or recurrent wet floors if water entry has been a problem.
Light superficial rust on a Lally column base is not structurally significant, though it might indicate a history of wet floors in the area. The rust shown at the Lally column base at below left is just a chip, it is insignificant, and we concluded that there was no evidence of a history of wet floors in this basement area. The steel column at below right penetrates the floor slab - we think it may sit on a hidden pier (there was no sign of settling).
But the column surface rust at be;pw right suggests the floor has been wet in this area. We did not think this column had suffered damage that risks it's structural integrity. Click this link to see another photo of rust on the base of a steel column in a basement that we verified over a 12 year life had been subjected to recurrent wet floors but never flooding.
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Comparing Surface Rust to Significant Exfoliating Rust on a Structural Column
But when we see exfoliating rust, some careful poking around to see just how much damage has occurred can help us decide the urgency of replacing the column - and of course fixing the water entry problem . WATER ENTRY in BUILDINGS will help with the latter.
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Example of Structural Steel Column Collapse Due to Rust
At below left we show serious exfoliating rust at the base of a steel column. It's reasonable to infer that this home has been subject to recurrent flooding to a depth of several inches.
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Our second structural rust photo (above right) was very exciting. We were inspecting a house on Long Island when the owner mentioned that she had pumps running 24/7 in the basement to keep Long Island Sound at bay. There was a forest of steel supporting columns (some were just hollow pipes not real Lallys) in this home's basement - all were badly rusted.
As the owner, who was a big person, walked across the floor, the kitchen floor suddenly collapsed and fell down about a foot. We wondered if an earthquake had suddenly struck Long Island.
Trembling we both took another look in the basement. The Lally column shown above and supporting part of the kitchen floor had picked that moment to crush. It was rusted through from repeated flooding.
Also see FLOOD DAMAGE TO FOUNDATIONS. For problems with settlement of piers below Lally columns see Settlement Cracks in Slabs.
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Frequently Asked Questions (FAQs) about damaged structural columns in buildings: inspection, diagnosis, repair
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
- "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
- 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, 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
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
- Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
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The Home Reference Book - the Encyclopedia of Homes
- 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 for structural crack monitoring
- Basement Moisture Control, U.S. Department of Energy
- 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, U.S. Department of Energy
- 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
- Energy Recover Ventilation Systems for Buildings, U.S. Department of Energy
- Energy Savings Methods: Whole House Systems Approach, U.S. Department of Energy
- Historic Preservation Technology: A Primer, Robert A. Young, Wiley (March 21, 2008) ISBN-10: 0471788368 ISBN-13: 978-0471788362
- Log Homes: Minimizing Air Leakage in Log Homes, U.S. Department of Energy
- Log Homes: Controlling Moisture in Log Homes, U.S. Department of Energy
- Log Homes: Log Home Design, U.S. Department of Energy
- Moisture Control in Buildings, U.S. Department of Energy
- Moisture Control in Walls, 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
- Natural Ventilation for Buildings, U.S. Department of Energy
- R-Value of Wood, U.S. Department of Energy
- Spot Ventilation for houses, U.S. Department of Energy
- 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", U.S. DOE: how vapor barriers work, types of vapor diffusion barriers, installing vapor barrier
- Ventilation for energy efficient buildings, Purpose, Strategies, etc.,