When calculating the maximum floor area of the new building, I would like to utilize the allowable area increase for sprinklers as specified in section 506.3. However I am uncertain how one would apply the allowable area increase specified in Section 506 since the existing building is non-sprinklered
I am assuming that the allowable floor area for each building should be calculated individually per equation 5-1, using Is=0 for the non-sprinkled building and Is=2 for the new building, then insure that the sum of the actual/allowable floor area ratios does not exceed one as outlined in section 508.3.3.2. However since both buildings are of the same occupancy, I am uncertain if this is acceptable.
Is there anywhere in the code that addresses allowable areas for multiple buildings when one building is sprinklered and one isn’t?