Private Specs Offer Producers a Common-Denominator Mix Design Win

Commercial contractors performing non-department of transportation (DOT) work are seeing more mix design requirements and quality control/quality assurance (QC/QA) parameters incorporated into bids. Specs like density requirements and percent within limits (PWL), once reserved for state projects, are showing up in private, municipal and maintenance contracts at an increasing rate. While this introduces new challenges, it also opens the door to a more streamlined, more consistent approach to mixes across a region. Let’s look at how that can be a boon to hot-mix asphalt (HMA) producers.

Contractors like Andersen Asphalt in West Haven, Utah, illustrate how private-sector expectations have risen. Jared Hislop of Andersen described an internal philosophy that predates incoming QC-focused contracts: “We bid all jobs the same way with the same expectations of quality.” Andersen’s process, which involves pressure-washing pavements before spray-applied surface treatments, adds time and cost but extends pavement life dramatically.

As more owners shift toward quality-based decisions rather than low-bid selection, contractors with established best-practice processes find themselves aligned with the new requirements. But for many in the industry, the bigger story is the mix design standards being written into commercial contracts.

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Why State-Level Specs Are Spreading

In 2025, Pavewise CEO Bryce Wuori encountered a commercial project with a custom PWL spec. “They’re looking for longer-lasting parking lots,” Wuori explained. Engineers who work with DOTs often drive these changes by recommending the same “state” standards for private owners.

But the momentum isn’t only coming from engineers consulting on the projects. Municipalities, counties, and turnpike authorities that previously wrote their own specs are increasingly adopting state-DOT mix designs. The primary reason, Wuori noted, is the available testing infrastructure. But the secondary reason reveals an industrywide advantage: streamlining.

“A large asphalt producer like Reith-Riley might have 20 different mix designs because there’s one for the DOT, there’s one for the city, there’s one for the municipality, there’s a city patching mix, and so on. It’s cheaper for asphalt facilities if you start to provide fewer options for mixes to reduce complexity and cost. So, the industry move for specifications is toward what’s common.”

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The Power of a Common-Denominator Mix Design

Among the emerging QC/QA trends, the push toward a common-denominator mix design for a region may be the most transformative. When one region aligns on the same high-performance mix that is already tested, verified and commonly produced, several benefits emerge.

First, producers gain efficiency. The plant can run a single mix all day without recalibration, thus reducing waste and cutting production costs. Second, the consistency improves QC outcomes with predictable acceptance testing. Third, owners gain reliability without reinventing the wheel. As Wuori pointed out, owners are asking, “What mix does the state already require that works in this environment?” Choosing the DOT-approved regional standard eliminates the cost of developing custom commercial specs. Fourth, contractors are bidding apples to apples.

This harmonized approach creates downstream efficiencies when adopted commercially.

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A Reality Check

Not every engineering-written spec hits the mark. The key is working together. As Bowes Construction’s Kesmond Willert observed, “Engineering firms and contractors must work collaboratively, respecting both the technical design and the practical realities of construction.” He noted that engineering support can protect owners’ interests, while contractors must speak up when real-world adjustments are needed.

Hislop highlighted another challenge: inconsistent enforcement. If a contractor wins a job by ignoring application rates or quality requirements, then no one verifies the work, it undermines the companies that are committed to doing the job correctly. Strong relationships with engineers and consistent enforcement of standards help close that gap.

Despite regional differences, the trend toward more structured QC/QA creates several industrywide benefits. It levels the bidding field, helps owners understand what they’re buying, protects contractors with third-party verification, and raises long-term pavement performance.

For producers, the benefits are even clearer. The gradual shift toward fewer mix designs common to an entire region simplifies production, reduces errors and aligns commercial work with the state-approved processes already familiar to most plants.

The industry’s increasing use of DOT-like standards in commercial projects reflects a growing desire for durability, consistency and accountability. But the biggest advantage may be the movement toward a common-denominator regional mix, which is a change that lowers producers’ costs, improves uniformity, simplifies testing, and gives owners and contractors a proven, climate-appropriate material.

Instead of a burden, the approaching spec-driven environment can serve as a catalyst: streamlining production, aligning expectations, and elevating the entire industry’s performance from plant to pavement.