Shoring Posts: The Rating Is Only One Part of the Support

Choose shoring posts from the load each post must carry, its installed height and the surface beneath it. Then check head fit, bracing and access for installation and removal. A post that reaches the beam and has a large advertised capacity is not necessarily a suitable support.

Shoring posts are commonly adjustable vertical supports used beneath floor formwork, beams or existing framing during construction and repair. For example, Doka’s Eurex top props are telescopic steel supports intended for vertical load transfer in floor systems, temporary reshoring and free-standing applications. Their use outside those conditions requires the manufacturer’s written approval. Doka’s August 2025 user information defines those limits.

Match the post to the job

Similar-looking products can have different purposes:

• Formwork props support the specified formwork system or serve as reshoring within documented conditions.
• Repair jack posts provide temporary or additional support while framing or primary supports are repaired.
• Lifting shores are specifically designed for adjustment under load. Ellis’s lifting shores, for example, use thrust bearings to ease that adjustment. Do not assume an ordinary support prop has the same capability. Ellis lifting-shore specifications
• Permanent supports need both a product intended for that use and a suitable structural design, foundation and connections.

“Adjustable” does not mean “approved permanent column.” Tiger Brand explicitly states that its floor/telescoping jacks are not intended for permanent, primary support. Ellis, by contrast, markets particular steel shores for temporary or permanent installations. Neither statement establishes that a particular building installation is adequate; verify the exact product and project requirements. Tiger Brand’s limitations and Ellis’s product descriptions illustrate why the distinction matters.

For wall removal, settle the existing load path before selecting posts. Our guide to identifying a load-bearing wall explains the framing clues and their limits. Have a structural engineer establish the temporary support arrangement and load-transfer sequence rather than choosing spacing from the wall length alone.

Read the capacity at the installed height

Three numbers must not be confused: failure load, allowable support load and lifting capacity.

Tiger Brand’s J-S-100, for example, lists a compression-load range of 18,000 to 9,100 lb. Its footnote says these are tests to the point of failure, with maximum loads at minimum extension; it directs users to a licensed engineer to determine safe or allowable loads. An “18,000 lb” listing therefore is not permission to place an 18,000 lb service load on that post. Manufacturer’s load table

Extension and configuration also matter. A longer compression member is generally more vulnerable to buckling. Doka’s permissible-load tables distinguish extension length, outer-tube position and free-standing versus specified clamped applications. Its manual also specifies a 20% reduction when using its 0.50 m floor-prop extension. That is a product-specific rule, not a general derating formula for other posts. Doka load tables and extension warning

Before ordering or renting, obtain these answers:

Selection input	What must be established
Load per post	The reaction assigned to that post by the support design—not total load divided by post count without justification
Working height	Installed length, including the specified head, sill and permitted packing
Allowable capacity	The exact model’s rating at that height, orientation and restraint condition
Bearing and connections	What carries the load above and below, and how movement is prevented
Task and access	Support or lifting; room for adjustment, bracing, inspection and eventual removal

If a rental quote gives only a maximum capacity, ask for the applicable load chart and assembly instructions. Use the current documentation for the exact model and region of use.

Check the complete load path

The support system runs from the framing or formwork, through the head and post, into the sill, slab, footing or ground. A stronger post does not strengthen a weak bearing surface.

For U.S. cast-in-place concrete work, OSHA 1926.703 requires sound, rigid sills capable of carrying the maximum intended load. Base plates, shore heads, extensions and adjustment screws must be in firm contact, with securing where necessary. Off-center loading on shore heads is prohibited unless the members were designed for it.

On repair work, the same load-path questions need explicit design answers: Can the slab carry the concentrated reaction? What supports a suspended floor beneath the post? Does the head distribute load adequately into the beam? Loose scraps under a base are not a substitute for a specified bearing detail.

Keep vertical props plumb and follow the required lateral restraint details. Doka requires full-surface baseplate contact on adequately load-bearing ground and warns that its folding tripod is a setup aid, not a substitute for tower bracing. It also prohibits stacking these props and replacing their pegs with rebar or anchor rods. Doka assembly restrictions

Inspect, load and release under a defined plan

Before erection, check model identification, tubes, welds, plates, threads and locking components against the manufacturer’s acceptance criteria. Quarantine questionable equipment rather than assuming a dent or damaged thread is harmless.

For cast-in-place concrete, OSHA requires inspection before erection and immediately before, during and immediately after placement. It also prohibits adjusting single-post shores to raise formwork after concrete placement. Although OSHA sets special design, inspection and bracing requirements for tiered single-post shores, those provisions do not override a manufacturer’s prohibition on stacking its product. OSHA shoring requirements

Define the release condition before loading the posts. For elevated concrete slabs and beams, removal depends on sufficient concrete strength to carry self-weight and superimposed loads, established by following removal conditions in the plans and specifications or by appropriate ASTM strength testing—not simply elapsed days. Reshoring is required where the concrete must support loads beyond its capacity as the original forms and shores are removed. OSHA removal and reshoring requirements

For structural repairs, the engineer’s sequence should specify when the permanent support can take over and how temporary loads are released.

The useful purchase specification is therefore not just “shoring post, 10,000 lb.” It identifies the model, allowable load at working height, head and base details, restraint, intended task and removal conditions.