Renting a Rebar Bender vs Ordering Pre-Bent Rebar

Renting a rebar bender makes sense for a handful of bends in 10M or 15M bar, for field-fit pieces, and for repairs. For repeated shapes such as stirrups, ties, hoops and footing L-bars, and for anything 20M and larger, ordering pre-bent rebar from a fabricator usually costs less once crew time, waste and rework are counted. The rental rate is the smallest part of the cost of bending your own bar. The bigger parts are the hours your crew spends bending instead of placing, and the bars that come out wrong.

This post looks at what you can rent, what rental cost really depends on, and how to decide between bending on site and ordering shop-bent bar. For the bending technique itself, see our guide to how to bend rebar, and for the field vs shop rules, see can rebar be bent or cut on site.

What you can rent

Equipment rental stores in Ontario commonly carry some or all of these:

Check the rating against your bars. Many portable tools are made for the US market and rated in US bar numbers and strength grades. The diameters line up roughly like this:

Size is only half of it. A bender is rated for a bar size at a certain strength, and stronger bar takes more force. If your drawings call for 500W bar, ask the rental store whether the tool's rating covers it.

Check the pin. The bend diameter is a code requirement, not a preference. CSA A23.1 sets minimum finished bend diameters by bar size, grade and use, and stirrups and ties bend tighter than main bar hooks. A rental bender comes with whatever pins or rollers it comes with. If they do not match the diameters on your drawings, the bends will be wrong even if the angles are right. Our metric rebar bending chart lists the finished diameters.

What rental cost really depends on

We do not quote rental rates, and they vary by store, season and tool. What drives the total is predictable:

• Rental period. Daily, weekly and monthly rates differ, and a job that runs long pays for more days.
• Delivery and pick-up for heavier units.
• Deposit and damage terms, including blades and pins.
• Consumables, such as cut-off discs and replacement blades.
• Power. Electric benders and cutters need a suitable circuit or generator on site.
• Your crew's time, which is usually the largest item and the one most often left out.

The costs that don't show up on the rental bill

Bending on site carries costs that never appear on an invoice:

• Learning time. The first pieces take longest, and getting consistent leg lengths on a bender takes practice.
• First-piece checks. Every new shape should be checked against the drawing before the rest are bent.
• Rework and scrap. A bar bent to the wrong dimension usually cannot be straightened and rebent. Our post on whether bending rebar weakens it explains why.
• Waste from stock lengths. A shop plans cuts across a whole job to use stock lengths efficiently. On site, offcuts pile up.
• Sorting and identifying. Shop bar arrives tagged and bundled by mark. Site-bent bar has to be counted and sorted by hand.
• Weather. CSA A23.1 limits bending in cold conditions, which matters for outdoor bending in an Ontario winter.
• Schedule. Every hour spent bending is an hour not spent placing. On a tight pour date, that is often the deciding factor.

What ordering pre-bent rebar involves

Ordering cut and bent bar from a fabricator works from a bar list: each bar mark with its size, grade, shape, dimensions and quantity. If you do not have a bar list, the fabricator can take off the job from your structural drawings and detail it. The bar is then sheared to length, bent to the listed shapes, tagged by mark and bundled for delivery. Shop bending is done within the standard fabricating tolerances in RSIC practice, covered in our post on rebar fabrication tolerances.

The trade-offs are lead time and certainty. You need your bar list or drawings ready early enough for the shop's schedule, and a dimension that changes on site after the order is placed can leave a bar that does not fit. Our guide to ordering cut and bend rebar covers how to write an order that avoids that.

Side by side

A sensible split for most jobs

Most contractors end up in the middle:

1. Order the repeated and larger shapes pre-bent. Stirrups, ties, hoops, L-bars, dowels and any bar 20M or larger.
2. Order straight bars cut to length where lengths are known.
3. Keep a few extra straight bars for field fit, and rent or own a cutter for trimming.
4. Rent a bender only for the leftovers, such as a few site-measured pieces around an opening or a repair.

That keeps the crew placing steel instead of making it, and keeps a small amount of flexibility for the dimensions that are only known once the forms are up.

Safety notes if you do rent

• Read the operating instructions and use the guards. Benders and cutters have pinch points that can take fingers.
• Wear gloves, eye protection and safety boots, and keep the swing area clear; a bar can whip when it slips.
• Stay within the rated capacity. Overloading a bender can break pins or fling the bar.
• Only bend loose bars. Bending bars already cast in concrete needs the engineer's approval.
• Never heat bar to make it easier to bend unless the engineer has approved a procedure.

Get it bent in the shop instead

We shear bars to length and bend them to all standard shapes from 10M to 55M, then tag and bundle each mark so your crew can place them without sorting or bending on site. We also prepare bar lists from your structural drawings, supply fabricated dowels and stirrups, and deliver across the GTA and Ontario. Send your drawings or bar list for a free quote and compare it with the cost of bending your own, or see our services.