When I saw my first hole in a concrete support post, I stopped and looked at it a little too long. It turns out that these holes are often related to precast column lift points. A solid post, a nice circle of nothingness, no apparent wire, no pipe, no other explanation for its existence.
If you start to see these openings on multiple posts, it starts to look suspicious. As if some portion of the work was overlooked or as if the project was never completed.
However, most of the time the solution to this mystery is simple. The holes in a series of posts are often column lift points. These were intended to be a conduit for the construction crew to use when placing the columns. The crew could then use these openings to safely hoist, rotate and set the column in place.
Why The Holes Repeat On Every Column
Precast concrete columns are built off-site. They are then taken to a jobsite and placed using a crane. This leaves the construction crew with no viable option to safely hoist, rotate and position the column.
This is where precast column lift points come into play.
A lifting pin, rod or rigging attachment is run through the opening on each side of the post. This allows the crew to safely hoist, rotate and lower the column in place. Once the column is placed and anchored in place, the hole is no longer needed. Essentially, it is a remnant of the construction process.
Why The Holes Repeat On Every Column
Consistency is the key here.
One post having a crude hole drilled into it is a concern. However, when every post has the same size opening at roughly the same height, this usually indicates that the detail was included in the initial fabrication and erection plan.
With pre-cast construction, crews will perform the same task over and over again with each identical component. The reasons for this include; safety, speed and control of the lifting process.
As such, the repetitive openings do not happen by chance. Rather, they indicate that the columns were fabricated and erected utilizing the same lifting procedure.
