St. Charles Parish and School
Single-Ply & Coatings Project Profile

St. Charles
Parish and

Spokane, WA

Completion Date: October 2014

Building Overview 

  • St. Charles Parish began construction in 1959 and finished in 1961. It is similar to construction used in Europe and Russia, but the hyperbolic paraboloid roof was quite new at the time in the U.S. The building has seating for 800 people inside.

The Challenge

  • Rev. Thomas Connolly needed to reroof his church, but he knew it would be a difficult project, since the church features what is believed to be the only unbalanced hyperbolic paraboloid roof in the world. John Kidwell, president of All Surface Roofing and Waterproofing Inc. and his crew first had to remove a layer of spray polyurethane foam (SPF) that was breaking loose at the roof perimeters. Beneath the SPF were two built-up roofing systems and other coating products that contained asbestos. All of these systems had to be removed from existing wood and concrete decks. 


  • Kidwell’s crew removed the asbestos and tested it to make sure it would not break loose and become airborne. After the asbestos was properly disposed, they were ready for reroofing. This project required three different roof systems: high-definition asphalt shingles, TPO single-ply roofing, and coating for the wing-like concrete roof. Luckily, all were under GAF’s guarantee.
  • GAF’s Tiger Paw™ Roof Deck Protection was used for the steep slope while WeatherWatch® Leak Barrier was used for the eaves, valleys, chimneys, and other areas.
  • GAF Timberline HD® Shingles in Barkwood were the asphalt roofing shingle choice.
  • On the low-slope section, EverGuard® TPO 60 mil Tan was adhered over EnergyGuard™ Polyiso Insulation and a ¼" gypsum board were mechanically attached to the deck. The upgraded insulation will help enhance the building’s energy efficiency. 
  • TOPCOAT® Membrane, a water-based, spray-applied liquid elastomeric roofing system, was applied to the concrete deck.
  • The 800-square-foot project took four months to complete. Kidwell estimates a 25-year service life for the three different systems used on the roof.

Materials Used

Tiger Paw™ Roof Deck Protection

WeatherWatch® Leak Barrier

Timberline HD® Shingles

EverGuard® TPO 60 mil

EnergyGuard™ Polyiso Insulation

¼" Gypsum Board

TOPCOAT® Membrane

Job Details

Spokane, WA
Job Size
80,000 square feet
Building Owner
St. Charles Catholic Church
Roofing Contractor

All Surface Roofing and Waterproofing Inc.

P.O. Box 18806 Spokane, WA 99228

(877) 732-ROOF

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