A medical office building (MOB) in Gresham operates under federal ADA accessibility obligations, with the local healthcare-system context shaped by the Legacy Mt Hood Medical Center corridor and the private MOB cluster along Powell Boulevard and Division Street. The 2010 ADA Standards for Accessible Design, Section 406, set the slope, width, landing, and detectable-warning requirements. Outer-east Multnomah County freeze-thaw shifts existing ramp compliance over time -- a ramp poured to spec in 2010 may have drifted out of compliance by 2026 because of frost cycling. Cojo installs ADA-compliant curb ramps at Gresham MOBs, and this guide explains the scope.
ADA 2010 Section 406, the Practical Spec
Section 406 sets a running slope of 1:12 maximum (8.33 percent), a cross slope of 1:48 maximum (2.08 percent), a ramp width of 36 inches minimum, and a level landing at the top of the ramp at least 36 by 36 inches. Flare slopes on the sides where they transition to the adjacent walking surface are limited to 1:10 (10 percent) maximum. Detectable warning surfaces (truncated domes) are required at the bottom of every ramp meeting a vehicular route -- they extend the full ramp width and 24 inches deep in the direction of travel.
In Gresham, the most common compliance failure is frost-heave-driven cross-slope drift on ramps installed before the deeper-aggregate-base discipline became standard. A digital-level field measurement during inventory walk catches this. See ADA curb ramp slope requirements for the field protocol and remediation options.
Outer-East Freeze-Thaw and Sub-Base Discipline
Gresham sits at slightly higher elevation than inner Portland, and freeze-thaw cycles hit ramp sub-bases harder. Frost depth in outer-east Multnomah County runs 6 to 10 inches in typical winters versus 3 to 6 inches in inner Portland. Ramps poured with a 4-inch aggregate base (an inner-Portland-spec) tend to heave 1 to 3 percent on cross-slope after 5 to 10 freeze-thaw cycles.
The standard fix on Gresham MOB ramps is an 8-to-10-inch compacted aggregate base under a 6-inch reinforced slab. That section adds 15 to 25 percent to the concrete line versus an inner-Portland-spec, but it holds compliance through the freeze-thaw cycle count. The economics almost always favor the upgrade because the alternative is a 5-to-10-year tear-out cycle.
Multnomah County and City of Gresham Permitting
City of Gresham permitting for ADA curb ramp installation depends on scope. A single-ramp replacement on an existing accessible route falls under a minor public-works permit. A multi-ramp project affecting pedestrian circulation may trigger a site-development review. Gresham Public Works coordinates with Multnomah County on ramps interfacing with public right-of-way.
For MOBs on the Legacy Mt Hood campus, the facility's ADA transition plan drives the scope. Legacy Health maintains field-measured ramp inventories at all their campuses, which streamlines bid-document preparation. Private MOBs along Powell and Division often lack inventories and require a field-measurement walk as part of the bid.
Industry Baseline Range
| Project Type | Cost Per Ramp | Typical Project |
|---|---|---|
| Single ramp replacement (frost-rated) | $2,000 to $5,000 | $2,000 to $5,000 |
| Multi-ramp replacement (5 to 10 ramps) | $1,700 to $4,200 per ramp | $8,500 to $42,000+ |
| Ramp + adjacent sidewalk panel | $2,700 to $7,000 | $2,700 to $7,000 |
| Detectable warning retrofit (only) | $400 to $1,200 per panel | $400 to $12,000+ |
Current Market Reality
Gresham MOB ADA scopes rarely land at baseline. The frost-rated sub-base premium, after-hours premium labor, ambulance-access traffic-control at Legacy Mt Hood, hidden sub-base conditions on older private MOBs, and concrete-cure waits in cool shoulder-season pours all push the real number up. The frost-rated upgrade is non-negotiable in Gresham; the only question is whether the rest of the scope holds at baseline.
Phasing Around Clinic and Climate Windows
Most Gresham MOBs operate Monday-through-Friday clinic hours with reduced weekend coverage. The cleanest phasing window is Friday evening through Sunday afternoon. High-early-strength concrete mixes get the ramp back in service within 24 to 48 hours. Legacy Mt Hood's 24/7 emergency operations require an even tighter window for ramps affecting ambulance-access, often confined to a 6-to-8-hour overnight pour with the ramp barricaded until cure.
The Gresham concrete-pour clean season runs late May through mid-October, with shoulder-season pours requiring blankets or heated enclosures. Cojo's concrete services schedules the work inside that window where possible, with related Gresham parking lot striping for ADA accessible stall layout and ADA signage post-install. The Oregon asphalt paving cost baseline covers parking-lot scopes including both asphalt and concrete work.
What the Practice Manager and MOB Operations Lead Decide
The buyer at a Gresham MOB is usually the practice manager (single-tenant MOB) or the MOB operations lead (multi-tenant MOB). Three levers move cost: scope (single ramp, full inventory, or partial), schedule (single weekend or multi-weekend phasing), and concrete mix (standard cure or high-early-strength). For an active ADA complaint, the high-early-strength mix wins.
For MOBs that are part of a campus ADA upgrade, bundling the curb ramp work with parking-lot restripe per hospital and medical office striping discipline reduces mobilization overhead by 10 to 15 percent.
Common Failure Patterns Found at Site Walks
A site walk of an existing Gresham MOB accessible route surfaces three outer-east-county failure patterns. The first is frost-heave cross-slope drift -- a ramp poured to 1:48 in 2010 may now read 1:35 or worse after a decade of freeze-thaw cycling on an insufficiently-deep aggregate base. The second is detectable-warning panel failure where the embedded truncated-dome surface has cracked or lifted from frost cycling underneath. The third is flare-slope spalling at the side transitions where freeze-thaw has chipped the concrete edge below the 1:10 maximum spec.
The fix in every case is removal and replacement on a frost-rated sub-base. Patch repairs on heaved Gresham ramps almost never hold -- the underlying sub-base problem remains, the patch lifts inside one to two winters, and the cycle repeats. The economics almost always favor a single full-replacement scope over a multi-year patch-repair sequence.
Get a Gresham MOB ADA Curb Ramp Quote
Every Gresham MOB curb ramp scope sits on its own combination of frost-heave history, patient-access constraint, and clean-season pour window. The only way to land an accurate number is a site walk with field measurement of every ramp on the accessible route. Cojo is CCB licensed and insured and has installed ADA curb ramps at MOBs across outer-east Multnomah County from the Legacy Mt Hood corridor to private clinics along Powell and Division. Contact us at /contact to schedule the walk.