The Spokane Flour Mill
Coatings Project Profile

The Spokane
Flour Mill

Spokane, WA

Completion Date: 2006

Building Overview 

  • The Spokane Flour Mill, overlooking the majestic Spokane River, was built in 1890 and was the most modern mill west of the Mississippi River. Today it is home to boutiques, designer shops, galleries, and restaurants.

The Challenge

  • The original 12,000 square foot built-up roof was constructed using multiple layers of felt paper adhered with hot-mopped tar. The roof had been replaced and repaired numerous times in its 126 years of service, with leaks remaining a persistent problem. The old building was also difficult to keep cool in the summer months, with temperatures that frequently topped 100°F.


  • When the summer of 2006 again found the roof in need of repair, United Coatings™ Roof Mate Coating, an elastomeric roof coating, was chosen to prevent further leaks and reduce the interior temperatures. The process began with a prime coat of Unibase, a low-viscosity material that flows easily into cracks and crevices, to seal the existing substrate.
  • United Coatings™ Roof Mate Base Coat was then applied to build up the membrane thickness and provide long-term crack bridging and durability. All components of the United Coatings™ Roof Mate Coating are advanced acrylics and possess an optimum balance of physical performance properties. These characteristics make them less susceptible to thermal movement due to the fact that the coating system will stretch and flex with expansion and contraction within the roof.  

Key Facts

  • The roof was top-coated with United Coatings™ Roof Mate Coating tinted to Bright White, which is formulated to provide long-term weather resistance while reflecting up to 85% of the sun's harmful UV rays. Sustainable warranties are available, as a United Coatings™ Roof Mate Coating is designed to last indefinitely with proper maintenance and periodic recoating.

Job Details

Spokane, WA
Job Size
Job Size: 12,000 square feet

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