Seismic Issues

Seismic Issues
No modern masonry chimney, reinforced and strapped to the house as required by code, has failed that we know of in recent American Earthquakes.

Tall and unreinforced

In the Northridge and Loma Prieta quakes in California and the Nisqually quake in Washington many old chimneys - even tall chimneys - did not fail. Even near the epicenter, many old and un-reinforced chimneys were not damaged.

The chimneys that did fail were, by in large, already in poor condition and in need of ordinary maintenance. Chimneys that served fireplaces and not furnaces generally faired better. Many of the chimneys that failed were lined with small metal flues indicating that a gas furnace had been vented into the chimney, and that probably the chimney had been damaged by acid flue gas condensation before the lining was installed. Chimneys that were poorly built to begin with or that were not maintained were the ones that failed.

Again, we found no modern masonry chimney built to code that failed in any of the three earthquakes.

Excerpts pertaining to masonry chimneys from a 1994 article by Richard E. Klingner, "Performance of Masonry Structures"

The Nisqually Quake And Masonry chimneys a report prepared by Jim Buckley for FEMA