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What is union scale in construction?

Union scale is the hourly wage and fringe benefit package set for a trade in a collective bargaining agreement between a union and contractors, and it often becomes the prevailing wage on public work in areas where union rates are the most common.

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Union scale is the negotiated rate a union contractor must pay its workers in a given trade and area. It is spelled out in the collective bargaining agreement (CBA) between the local union and the contractors or contractor association that signed it. Scale includes the base hourly wage and a set of fringe contributions, typically to health, pension, apprenticeship, and other funds, plus rules for overtime, shift pay, and travel.

The phrase also gets used loosely by non-union contractors to mean "the going union rate" when they bid public work, because union scale frequently shows up as the prevailing wage in a wage determination.

How union scale works on a real job

Say a signatory electrical contractor is pricing a $900,000 school renovation. The local inside wireman agreement sets journeyman and apprentice rates, with apprentices paid a percentage of journeyman scale that steps up by period. The estimator builds a crew mix (one foreman, three journeymen, two apprentices), applies the CBA rates to each, adds payroll taxes and insurance, and arrives at a blended hourly cost.

Example: blended crew rate (illustrative numbers only)
ClassificationWorkersWage + fringe per hourCrew cost per hour
Foreman1$78.00$78.00
Journeyman3$70.00$210.00
Apprentice (3rd period)2$44.00$88.00
Total6$376.00

Those rates are made up for the example. Real scale comes from the current CBA, and most CBAs change rates on scheduled dates during the agreement, so a job that runs a year may cross a rate increase. Price it in.

Union scale and prevailing wage

On Davis-Bacon and similar public work, the U.S. Department of Labor surveys wages paid in an area and publishes wage determinations. Under 29 CFR 1.2, the prevailing wage is the wage paid to the majority (more than 50 percent) of workers in a classification. If no single wage reaches a majority, it is the wage paid to the largest group, as long as that group is at least 30 percent of those employed. If neither test is met, it is a weighted average. When a union rate meets the majority or 30 percent test, the published prevailing wage matches union scale for that classification. That is why non-union contractors bidding Davis-Bacon work often pay union-level rates in some counties and much lower rates in others.

Common mistakes

  1. Using last year's rate. CBAs often have scheduled increases. Check the effective date of each rate before bidding.
  2. Forgetting fringe rules. Union fringes go to specific funds. On prevailing wage work, paying the equivalent in cash or plans has its own rules; see fringe benefits.
  3. Wrong apprentice ratios. Apprentice rates only apply to registered apprentices within allowed ratios. See apprentice ratio.
  4. Mixing classifications. Paying a worker at a lower classification than the work performed is a common audit finding.
  5. Ignoring travel and shift rules. Subsistence, zone pay, and overtime triggers in the CBA change the real cost.

Related terms

See journeyman, project labor agreement, and certified payroll. Smart Business Automator helps prepare certified payroll reports with classification and fringe detail for each worker on prevailing wage jobs.

Frequently asked questions

What does union scale include?

The base hourly wage plus fringe benefit contributions set in the collective bargaining agreement, along with rules on overtime, shift work, and travel.

Is union scale the same as prevailing wage?

Not always. Union scale becomes the prevailing wage for a classification when union rates meet the majority or 30 percent test under 29 CFR 1.2 in that area. Otherwise the prevailing wage may be lower or a weighted average.

Do non-union contractors have to pay union scale?

Only when a law or contract requires it, such as a prevailing wage job whose wage determination reflects union rates, or a project labor agreement.

How often does union scale change?

It depends on the agreement. Many CBAs set scheduled increases during their term, so check the effective dates in the current agreement.

Sources

  1. Cornell LII: 29 CFR 1.2, Definitions (prevailing wage)
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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