Washington County paving is metro-grade work. Hillsboro hosts Intel's largest U.S. semiconductor campus, Beaverton and Tigard run dense retail and office markets, Tualatin and Sherwood carry growing industrial corridors, and the whole county sits on Willamette Valley clay with a permit framework that takes traffic-control overhead seriously. A paving project here is not the same as a paving project in eastern Oregon. The mix design might be similar, but the schedule, the permitting, and the site-management work are all heavier.
This guide covers what asphalt paving costs in Washington County, the conditions that drive project scope, and what property owners need to know about permits, traffic control, and timing in the Portland metro west.
Hillsboro, Beaverton, Tigard, and the Intel Corridor
County seat Hillsboro anchors the western half of the county. The Intel campuses along NW Cornell Road, Hawthorn Farm, and the Ronler Acres complex drive a steady stream of paving work -- access roads, employee parking lots, fleet yards, and a constant cycle of pad work for new buildings. The semiconductor supply chain that orbits Intel adds another layer of industrial paving demand on lots that take 80,000-pound truck deliveries.
Beaverton and Tigard sit on the eastern side of the county and run a dense mix of retail centers, office parks, and apartment complexes. Washington Square mall, the Beaverton Town Square corridor, and the Bridgeport Village area drive commercial paving work where weekend-only schedules and overnight pours are common to keep retail traffic flowing. Tualatin and Sherwood run more industrial -- distribution centers, fleet yards, and food-processing facilities that demand heavy-duty paving sections.
Outside the urban core, Hillsboro Airport, the Tualatin Valley Highway corridor, and the agricultural-edge zones along the western county line each have their own paving profiles. The mix of urban density and agricultural fringe makes Washington County one of the most varied paving markets in Oregon.
Willamette Valley Clay and Metro Permitting
Washington County subgrade is Willamette Valley clay, just like the rest of the central Willamette Valley. That means deep silty-clay that drains poorly, expands and contracts with moisture, and pumps fines under traffic if drainage and base prep are not done right. The standard correction is 6 to 8 inches of crushed-rock base over a proofrolled subgrade, with a geotextile fabric layer over any soft spots that show up on the proof roll.
For commercial pads, Cojo specs 6 inches of base under a 3-inch compacted lift of dense-graded asphalt. Heavy-duty industrial pads at Intel suppliers or warehouse properties step up to 4 inches of asphalt over 8 inches of rock. Residential driveways typically run 2.5 inches over 4 to 6 inches of base.
Metro permitting adds work that smaller-county jobs do not. Hillsboro, Beaverton, and Tigard each have right-of-way permit requirements for any work touching public infrastructure. Traffic-control plans require flaggers or signed lane closures for arterial-frontage paving. Cojo handles the permit and traffic-control plan in-house on commercial work in this county, which is the only practical way to keep schedule and cost predictable.
What Goes Into a Washington County Paving Project
A correctly scoped Washington County commercial project includes site survey, geotechnical evaluation if the soils have a history of failure, demolition or scarification, sub-base placement (often with geofabric), aggregate base, hot-mix asphalt placement in the appropriate lift, edge rolling, breakdown rolling, and finish compaction. Striping, curb work, and ADA compliance items follow after the asphalt cures.
For lots over 1 acre, traffic-control plans, stormwater management, and erosion-control bonds are typically required. Many properties also need concrete curbing for Washington County as part of the paving package -- extruded curb integration is common in retail and industrial sites. After asphalt cures and curbs are placed, commercial parking lot striping closes out the site work.
Industry Baseline Range
| Project type | Typical scope | Industry baseline range |
|---|---|---|
| Residential driveway repave | 500 to 1,200 sq ft | $4 to $6.50 per sq ft |
| Small commercial lot | 5,000 to 10,000 sq ft | $3.50 to $5.50 per sq ft |
| Medium commercial lot | 10,000 to 25,000 sq ft | $3.25 to $5.25 per sq ft |
| Large commercial or industrial pad | 25,000+ sq ft | $3 to $5 per sq ft |
| Heavy-duty Intel-supplier or warehouse pad | Per project | $4.50 to $8+ per sq ft |
| Overlay (no full tear-out) | Per project | $2 to $4 per sq ft |
| Patch and repair | Per square foot | $3.50 to $8 per sq ft |
Current Market Reality
Washington County paving costs in 2026 carry a metro premium driven by permit overhead, traffic control, and prevailing-wage requirements on public-frontage work. Liquid-asphalt and diesel prices have lifted base mix costs roughly 25% since 2021, and Portland metro labor rates run above eastern Oregon rates by 15% to 25%. Disposal fees for tear-out material at metro transfer stations also add cost. Property owners comparing pre-pandemic quotes to today should expect 30% to 45% nominal increases. For statewide context, see asphalt paving cost in Oregon.
Best Paving Window for Washington County
The reliable paving window in Washington County runs mid-May through mid-October. The wet season is the real constraint -- Willamette Valley clay does not tolerate wet-weather paving. Surface moisture under the mat causes adhesion failures that show up as raveling and edge breakdown within two seasons.
Commercial retail paving is often scheduled overnight on Friday-Saturday or Saturday-Sunday rotations to avoid daytime traffic. Industrial paving at Intel campuses or warehouse properties runs on planned shutdown windows. Residential driveway paving fits anywhere in the season but books out fast in June and July.
Hiring a Paving Contractor in Washington County
The contractor for Washington County work needs metro paving experience, permit familiarity, traffic-control discipline, and the equipment to handle multi-acre commercial pads. Cojo Excavation and Asphalt serves the Hillsboro, Beaverton, Tigard, and Tualatin corridor with the crew size and equipment fleet that metro paving demands.
Request a quote for your Washington County paving project and Cojo will handle the site walk, permitting strategy, and schedule planning end-to-end.