Unlimited building area - two separate buildings on same site?

[aztec]

I've read a few posts and am still unsure. We are IBC 2012. I have a enough site to build a two story, B occupancy, Type VB, fully sprinklered "business" building! And used the unlimited building section. Then we were asked to add a small storage (B occupancy) to store computer parts, tools, etc. the additional building is within the 60' yard requirement for two story unlimited clause, but...we think we should be fine as we still have about 100' between our building(s) and property line. However, we didn't fully sprinkle the storage.

Now I'm unsure. We did draw the imaginary lot line between main building and little 800 SF storage. The distance is less then 40', so we moved the line placing 1 hr rated assembly on storage (30' from main building, 8 feet from storage) - keeping main building free and clear. Fully sprinkled storage? Not sure if we have to, but I don't want to lose the unlimited building area for main building.

I can't find this situation in code and have gone back and forth. We thought storage would come years down line but now....it's here to stay. Sprinkle storage would cost a lot, so I thought we would meet intent with FSD line. I thought as long as i keep my 60' yards and use fire sep lines, I should've fine. Maybe I'm in for a big surprise.

I hope I wasn't too confusing. Any thought or things i should read, please let me know. I appreciate your time.

 

[steveray]

Typically...if you can treat them as "one" it works, but I believe everything would have to be a 13 system....Other than that, the FSD and unlimited qualifiers would have to be met...