Their is no contradiction. You're mixing draft curtain requirements for a building without high-piled combustible storage (Table 910.3 in the IFC and IBC) with the IFC requirements for when draft curtains are required for high-piled combustible storage.

I seem to recall down this journey of the pellet storage building that you will not have high-piled combustible storage. You don't need draft curtains because your maximum building area is below the 50,000 square foot area threshold between each draft curtain.

Thanks Stookeyfpe, but let me understand your point:

I follow IBC and in 910.3.5 it says: "Where required by Table 910.3, draft curtains shall be provided in accordance with this section".  In my view, this paragraph is saying that the Table 910.3 determines when to use draft curtains.

For my particular case, High-piled storage, Class III (storage height=40 ft), the table shows minimum draft curtain depth 6 ft (Option 1) and maximum area formed by draft curtain = 8,000 ft. This means that my building (30,000 ft2) does need draft curtains per IBC. Note that my building is S-1 and high-piled storage, so my understanding is that I have to satisfy BOTH requirements in the Table and not only S-1.

And there is were I see the contradiction with IFC Table 2306.2 which for a 30,000 ft2 building, for high-piled storage, class III commodity does not require draft curtains.

Please help me to clarify this issue.

IFC/ [F] IBC Table 910.3 is not the determining table for high pile storage draft curtain installation.  IFC Table 2306.2 determines when draft curtains are required for high piled storage.

Note that IFC Table 2306.2 does not require draft curtains when the building is equipped with an appropriately designed fire sprinkler system, or is Class I-IV less than 2,500 or high hazard less than 500 square feet - high piled storage area.  

However; the IFC/ [F] IBC Section 910.2.1 still requires draft curtains at 50,000 sq ft, regardless of use (high piled storage or other use).  Both tables are required to determine application to high piled storage.

stookeyfpe is correct, there is no conflict.  

However, both tables must be used to determine high piled storage requirements. It might be helpful if a footnote was added directing IBC users to IFC Table 2306.2 for high piled storage draft curtain requrements.
 

I understand now.  As you said, IBC should be clarify by adding a reference to IFC table 2306.2

Thank you all