Strong maintenance of existing structures is far more cost effective than damage repair. In the Bay Area, however, serious restrictions may be imposed on the design of any new ediface. Consult with an EXPERIENCED Architect to determine not just Building Codes, but the preferences of City Planning Departments.
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Water damage to the inside of Commerical buildings is catastrophic, Insurance carriers may or may not cover preventable events such as leaks, floods and erosion due to poor maintain or careless Management.