Otta Seal

Cost-effective and Environmentally Friendly

What is an Otta Seal?

An Otta Seal is an asphalt surface treatment constructed by placing a graded aggregate (5/8-0) on top of a thick application of relatively soft bituminous binding agent (HFMS-2). The binder works its way into the aggregate with rolling immediately following the application and traffic over time. PLEASE NOTE: When performing a two layer Otta Seal you must allow 7-10 days between applications.

Interlocking Matrix

Closed texture creates a dense interlocking matrix. It promotes impermeability and protects the binder from direct solar radiation and associated oxidation and embrittlement.

Minimal Maintenance

Requires minimal maintenance, which helps lower the long-term costs and labor associated with road upkeep.

Lower Material Costs

Using locally sourced materials and less expensive materials (up to 20%) compared to the more traditional chip seal.

Gravel Road Appearance

Immediately after placement, the Otta seal’s appearance is similar to a gravel road and is influenced by the aggregate color. With time and traffic, the black bituminous binding agent works its way up through the aggregate, creating a surface appearance similar to cold mix asphalt concrete.

Reduced Surface Deformation

The treatment minimizes the risk of surface degradation due to thermal expansion and contraction, preventing cracking and pothole formation.

Low Environmental Footprint

By utilizing locally sourced materials and reducing the need for energy-intensive processes like hot-mix asphalt production, Otta Seal reduces carbon emissions and promotes environmental stewardship.

Special Note: Dust

After the Otta Seal application is in place and completed, during the initial sweeping process (gathering up excess rock left behind), expect an extreme amount of dust. Additional sweeping required 30 days after initial sweeping.

Life Expectancy

Life expectancy varies depending on construction materials used, environmental conditions, and traffic volumes. Reported serviceable lives for double Otta seals range from 8 to 15 years.

Optimized Moisture Management

By effectively sealing the road surface, Otta Seal mitigates the ingress of moisture, reducing the potential for water-related damage like erosion, base failure, or frost heave in colder climates.

Otta Seal Process

Sweeping and Cleaning

Sweep and clean existing roadway

Application of Otta Seal

Second layer Otta Seal

(7-10 days is needed before additional application)
Sweeping will occur in between applications

7-14 Day Sweeping and Cleaning

(Approximately 7-14 days after first application)
Please Note: Extreme dust will occur during this process

30 Day Sweeping and Cleaning

Approximately 30 days after all original sweeping, additional brooming may be required

Restriping Occurs (after 30 days)

After the 30 day additional brooming step.

Fog Seal Can Be Added (18-24 months approximate)

After Otta Seal is completed, roadway cure time of 18-24 months is needed due to PNW climate