Wendy,
Each individual state has different laws regarding these conditions. In Florida, if the previous architect finished the project and was paid in full, the client's committment to the architect and vice-versa has been satisfied. Since you state that the project is a renovation, I make that assumption.
Regardless, the original architect owns the right (US Copyright laws) to the documents that the firm prepared for the project, including the specifications. My best advice would be to contact the firm, let them know what you are doing and obtain, in writing, their permission to use the documents. In most cases it will take you writing the letter and asking for the original architect of record to "sign-off" granting you permission to use the documents.
I have done several projects where we have either taken over a defaulted project or a total remodel. This has always been my approach to the issue when using the work of another architect.
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Greg Burke, AIA
President
Gregory John Burke ' ARCHITECT, PA
Vero Beach, Florida
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