Okamoto-Saijo Architecture Home Okamoto Saijo Architecture designs green buildings. Since 1991, the firm has successfully stayed within budget on large scale affordable housing renovations; infused private residences with green materials and passive solar features; and enhanced community centers in support of neighborhood revitalization. Projects range from $150,000 to $44 million in size. OSA places special emphasis on integrity, practicality and quality. Os-architecture.com~Site InfoWhoisTrace RouteRBL Check