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During the winter months, the roof the historic Paradise Inn perched among the clouds on Mount Rainier often experiences an average of 53 feet of snow.

After a long history of handling that load, the roof of the historic 121-room hotel was feeling the effects of the burden. The log trusses of the Great Hall in the hotel’s lobby wing had deflected about 9 inches out of plumb. The weight of drifting snow had pushed the entire east wing out of plumb by about 8 inches. The effects were so severe that the wing was on the edge of possible collapse.

The National Park Service turned to KPFF Consulting Engineers for help with structural engineering design to save the 95-year-old landmark. Also working as consultants on the team tasked with saving the hotel were Fletcher Farr Ayotte, Interface Engineering and Watts Constructors/Korsmo Construction.

Three historic stone masonry chimneys were disassembled, with each stone labeled and its placement photographed before demolition. The chimneys were then rebuilt around post-tensioned concrete cores, which served as bracings for the structures. The new chimney systems combined with reinforced roof diaphragms, and concealed drag elements allowed the removal of four intrusive concrete shear walls that had been added to the building during a retrofit in the 1980s. Trusses and columns made from Alaskan Yellow Cedar that were rotting away were restored. The team even straightened the east wing using a cross cable system that allowed the building to slowly creep to its proper orientation, a position that was then secured by the addition of new wood shear walls and floor diaphragms.

By the time the hotel reopened to greet the first of the roughly 2 million visitors it serves each year, the structure had been upgraded to handle snow loads of more than 600 pounds per square foot of snow, pressure equivalent to four feet of concrete.