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RE: Wood Framing - Upgrade or Not

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Dennis  - You can count on Section 3403.2's exception in the 97 Uniform
Building Code (published by ICBO at 1-800-423-6587 for those who'd like to

Alterations of existing structural elements, or additions of new structural
elements, which are not required by Section 3401 and are initiated for the
purpose of increasing the lateral-force-resisting strength or stiffness of
an existing structure, need not be designed for forces conforming to these
regulations provided that an engineering analysis is submitted to show that:

1. The capacity of the existing structural elements required to resist
forces is not reduced.
2. The lateral loading to required existing structural elements is not
increased beyond their capacity.
3. New structural elements are detailed and connected to the existing
structural elements as required by these regulations.
4. New or relocated nonstructural elements are detailed and connected to
existing or new structural elements as required by these regulations, and
5. An unsafe condition as defined above is not created.

You might also try, if your code enforcer is willing,  Appendix Chapter 6 of
the Uniform Code for Building Conservation also by ICBO Section A601.3 which
provides for a reduced base shear V = 0.33ZW This section was not intended
to be just limited to cripple walls and bolting.

Basically you are encouraged by the Code to be creative in this situation
and take advantage of the window of opportunity and to consider options of
reducing future earthquake losses. Hope this helps (I suspect that you
personally know of these code sections, but others may not.)

Fred Turner, Staff Structural Engineer, California Seismic Safety
Commission, 1900 K St. #100, Sacramento, CA 95814 916-327-1606 Work Phone,
916-322-9476 Fax fturner(--nospam--at)