Yes, that's correct, building codes do have tables for common materials 
and loadings for smaller (up to say 3 family) residential structures. 
Generally for larger residential, commercial, and industrial structures, 
a PE's stamp is required. Sometimes an architect's stamp is sufficient. 
I am trying to caution people from hurting them self. It is important to 
understand the limitations of the tables. Sometimes those footnotes need 
an engineer to understand. Also many times the tables are only for the 
complete structure and construction loads, and the incompleteness of the 
structure could be dangerous. A very good example, within the last 5 -10 
years, the lateral stability of trusses including bar joists has become 
a construction safety issue. When first erected, these components can 
bend sideways and fail. Before the crane hook is unhooked it may be 
required to provide lateral (sideways) support.

Dave Lagzdin wrote:
> 2008/10/1 Carl Denk <cdenk@alltel.net>
>
>   
>> Actually OSB is fairly homogenous, and is used in large scale, where the
>> defects are accounted for in the allowable stresses. Plywood has
>> different allowable loading parallel and perpendicular to the grain of
>> the face ply. And all these formulas apply only in the linear zone and
>> less than the elastic limit (after deformation, the piece returns to
>> it's original shape when the load is removed), and all safe loading is
>> in this area.
>>
>> I can't caution enough, as a registered structural engineer though, 85%
>> of structural failures are details, connections, etc. , NOT the main
>> member (beam or column). Think Holiday Inn Kansas City where a small
>> connection killed and severely injured many; The I-35 bridge in
>> Minneapolis where a plate failed, and this isn't just big structures.
>> Compared to the entire structure, the cost of a competent engineer is
>> inexpensive, and may save money by recommending more economical material.
>>
>>     
>
> If this is building code NBC/CBC/local relevant there are tables for "silent
> joists" and paralams(sic?) etc. Deflections usually limited to 1/360 of the
> length IIRC.
> Anything not in table usually requires a stamp, even substituting two 2x10s
> with douglas fir 6x12...
> D
>   
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