Ridgecrest Single-Family Housing Study by Keith Porter

This contains new data about single-family dwellings. I wondered, why was damage to housing relatively modest in Ridgecrest? An understanding of what was there to be damaged could inform the answer. I collected data on a few key housing attributes from 200 houses on 5 residential blocks that I selected as a sort of cross section spanning from the northwest to the southeast corners of the city, as shown in Figure 1.

Table 1 presents these statistics of Ridgecrest housing. Ridgecrest’s buildings are mostly of types that do well in earthquakes, as these did. Homes are mostly single-story wood-frame buildings, slab on grade, with stucco walls, light chimneys (few brick chimneys), and light roofs (not mission tile). Wood is light, so it doesn’t attract much earthquake force. Slab-on-grade foundations avoid the weaknesses inherent in unbraced cripple walls. Stucco cladding greatly adds to the strength of the wall, acting like reinforced concrete skin. Chimneys that are constructed with insulated metal flues clad in wood do not suffer the weaknesses and widespread collapse that brick chimneys do. Composition tile roofs are light compared to mission tiles and further limit the seismic loads the walls have to carry.