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Founded In: 1986
Annual Vol: Undisclosed

Our Story

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Our capabilities include demolition, site excavation, trenching, side sewer installation and/or lining, import, export, trucking, and the full gamete of utility installation.  We install catch basins, electrical vaults, man holes, detention tanks, fire hydrants (we are certified to install fire water line). We have relationships with developers, and GC's that work on industrial facilities, for municipalities, for private and commercial building, as well as private/residential projects.

Cornerstone Construction of Seattle Inc. has been excavating and installing underground utilities in Seattle since 1986. Though most of our work has been within the City of Seattle we are extremely familiar with most of the region including the Eastside and up into the south of Snohomish County.

We are more than just another sub coming and going. We work to be the best partner we can be by openly communicating throughout the project.  We work to identify potential issues BEFORE they become that change order. We understand more than just installations, we understand the impact of our contribution to each project and work to make sure the job is done right and on budget.

What We Do

Products/Services Relating to Underground Utilities--Contractors
Products/Services Relating to Excavating Contractors

Project Experience

Project Types:
Service Work/Repairs
Civil & Site Development
Hotel / Motel
Grocery Stores
Medical Office

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Associations & Memberships

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