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split-column-supportAdjustable “split” jack posts or “split” steel columns are improperly used in many homes in New York and are a structural defect. When any of these split type or telescopic adjustable post or columns are installed with the intention of permanent use for the support of main beams in homes it is an improper and unsafe application for which they were not designed. All “split type” adjustable posts are for temporary use only.

What I am addressing in this article is the “split” type hollow steel posts or columns; where the steel column is two or more pieces that telescope, one fits inside the other and they are pined or bolted together. It’s confusing because they go by many names, most of which are used interchangeably to describe different types of split and non-split columns. There are many adjustable steel columns that are not split; they are a solid one piece steel tube with a threaded adjustable end. Many non-split adjustable posts are suitable for permanent use.

Adjustable “split” jack posts are also known as:

“Split posts or columns,” “steel posts or columns,” “split-pinned posts or columns,” “Lally columns,” “lolly columns,” “jack posts,” “jacks,” “screw jacks,” “adjustable floor jacks,” “floor jacks,” “house jacks,” “tele posts,” “sectional columns,” or “double-sectioned columns.”

Originally a lolly or Lally Column was a proprietary name for the concrete filled, solid steel column invented by John Lally. Many people feel that the term should only be spelled “Lally” and that it should only be applied to concrete filled steel columns. “ For more on the Lally Column see: John Lally History.”

So what makes up an adjustable “split” jack post?

Adjustable split jack post, partsThey usually come in two (but sometimes more) hollow steel tube sections with a threaded adjustment rod at one end and two small steel bearing plates one for each end. The smaller diameter tube(s) fit into the larger diameter tube(s) lining up the holes for the rough length adjustment. The sections held in place with steel pins or bolts which pass through the holes of both tubes. Then the threaded end section is placed at the top or bottom and is screwed for fine tune adjustment of height with a steel bearing plate at top and bottom.

No “split” jack posts are manufactured for permanent use in the USA. All home inspectors and code enforcement personnel should deem the permanent use of split jack posts or telescoping adjustable columns as a structural and safety defect in any home in the USA. This is a defect because no split jack post or telescopic adjustable column has been evaluated by a U.S. evaluation firm and none of their manufacturers cite an engineering report to prove these columns’ ability to carry a specific load. Also, according to the International Residential Code (IRC), a steel column has to be at least 3 inches in diameter. All split jack posts or telescopic columns are less than 3 inches in diameter.

Dangers of long term use of split jack posts

dangerous use of split jack postsRust, catastrophic structural failure and collapse are the potential dangers of using split jack posts or telescopic columns. When used in long term or permanent use there is the potential for loss of life and property. Should a sudden column failure occur, as sometimes happens, it could start a chain reaction of catastrophic failure of the floor structure and partial building collapse. The thin metal hollow tubes of these columns are not designed to withstand long term exposure to moisture and heavy pressures.

These temporary supports in long term use most often fail due to rust deterioration. These hollow tubes, especially at the bases are prone to rust, often buried in concrete or resting on cement floors or footers in damp or wet basements or crawl spaces. They are typically thinner gauge steel and cheaper quality than solid steel columns designed for permanent use and vulnerable to rust.

Their intended purpose is easily mistaken. With these adjustable split jack posts so readily available at most do-it-yourself big box, and hardware stores, home owners or the typical handyman can easily miss their intended use is only for temporary supports. Some manufactures don’t help matters with advertising on the boxes with claims of “give[s] lifetime support” and “For Remodeling and Additions” and “Corrects Sagging Floors, Supports Basement Beams” etc.

“As a home inspector I have a personal responsibility and a duty to my client to report the improper use of split jack posts or telescopic steel columns.”

My Home Inspection Report description of this defect

“Observed split-pinned or telescopic jack post(s) /column(s) in a permanent use application. All “split” type jack posts or telescopic posts/columns are designed for temporary use only; I recommend and strongly urge, for improved safety and structural integrity reasons, that the improperly used split-pinned or telescopic adjustable post(s) /column(s), those which have been installed as permanent supports, be replaced with proper cement filled “Lally” columns or approved adjustable solid steel columns designed for permanent use; Additionally…

… it should be ensured that the new columns have appropriately sized footings under each column or beneath the floor under the column if the column base penetrates the concrete floor slab; In such case where the floor was poured around the column base we can’t see if a proper pier or footing was installed to support the column base. Also note that when improper use of temporary split column(s) is present it could indicate the construction may not have been properly designed or that it may have been done without the proper permit or code enforcement.”

Split posts could indicate additional defects

If split or telescoping adjustable columns were installed when the home was built, it’s possible the builder may have cut corners else where such as the lack of sufficient foundation or load bearing support under the columns. So when I observe split jack posts being used in a permanent fashion I recommend they be replaced by a qualified contractor with proper supports and to ensure they are resting on proper footings. In some situations it may be wise to refer the matter to qualified structural engineer if additional issues are also involved.

Why is improper use of split jack posts so widespread?

With the with improper use of split jack posts or columns in so many homes, it does seem they were “allowed” practically speaking, at least locally and in many areas, for many years. It seems implausible that countless numbers of building code enforcement personal in different geographical areas could have missed such an easy to see defect in so many homes. I’m not certain why, if anyone knows and would like to weigh in on this it would be appreciated.

8 Reasons I blame for the widespread misuse of adjustable split posts

  1. Money. The telescopic or split adjustable posts or columns are less expensive.
  2. Time. They are faster to install.
  3. Laziness. They are easier to install.
  4. Availability. The telescopic or split adjustable columns are readily available at big box stores and small hardware stores nearly always as compared to the solid adjustable and Lally columns which are not as readily available, not stocked or by special order only.
  5. Lack of integrity, honesty and work ethic. I believe many builders have and do misuse split jack posts knowingly for a combination of the above four reasons, plus the next reason.
  6. No consequences. Many builders have gotten away with this, without consequence for the most part because code enforcement has overlooked this problem in many instances.
  7. Lack of Code enforcement. From my experience in the greater Syracuse area I know in many cases it seems the code enforcement personal are so over tasked, they simply cannot do all the inspections they should be doing. Only some things get inspected some of the time.
  8. Ignorance. I believe the average do-it-yourself homeowner and many handymen and beginning small time contractors simply are not aware of this problem. They see the improper use of the split posts all the time, thinking its normal use; and that’s what is available at the corner store. They don’t think twice about using them properly or not and most often split jack posts end up being used improperly.

Home buyers and the Home Inspection Report

In older homes there are usually many recommendations for components or items that can that can be improved, upgraded, replaced, or repaired for reason of improved safety or efficiency etc. However such recommendations are usually not required for the sale of the home or to be performed after the home is purchased. And such is life; many of these recommendations go unheeded, especially if they are expensive or complex.

The proper use of split jack posts

proper use of split jack postsFor all the bad press split jack posts have gotten here, they do have a good and purposeful function. The proper use of telescopic or split adjustable columns in construction is to adjust or level a structure before installing a permanent column; or, they may be used as temporary supports during the course of a building repair project but should be removed once the project is complete. You can actually rent split jack posts at some rental stores but it is usually cheaper to buy them if used for more than a day or two.

The picture to the left shows split jack posts being used temporarily for a sagging joist repair job until the permanent wood posts are in place. Now they can be easily removed. This is an example of proper use for split type jack posts.