Preserving the Library of Congress

Preserving the Library of Congress

To protect the priceless Library of Congress collection at the Madison Building, roof designers chose the heralded Siplast© two-ply modified bitumen system.

Protecting a nation’s heritage

The James Madison Memorial Building of the Library of Congress hosts thousands of employees, a stream of visitors, and irreplaceable historical documents, including the presidential papers of George Washington and Abraham Lincoln.
When an infrared survey showed the existing roof nearing the end of its life cycle, planners sought a reliable replacement and a strategy to do the work without disturbing the library operations or collection.

A steadfast roofing solution  

The choice for the new roof was easy: Siplast© Paradiene 20/30 system with Veral aluminum flashings. The 2-ply, SBS-modified bitumen system provides years of watertight protection in the most extreme environments and a reliable solution when leaks are not an option.
Getting the materials to the roof was trickier. In this busy section of the nation’s capitol, there wasn’t room for a crane or staging, so the contractor utilized a network of ramps, motorized buggies, and just-in-time deliveries. Together, the team safely installed a secure, reliable roof system.


  • The roof of the James Madison Memorial Building required 765 squares of material, or 76,500 square feet.
  • Siplast Paradiene 20/30 flexible membrane retains elasticity through severe solar load, ultraviolet rays, thermal shocks, water ponding, and extreme temperatures.