And then, moving on to sharing from another pole barn house challenge:
A CLIENT’S EXPERIENCE
We have a client in Colorado who has been trying to get a permit to build his combination garage and pole barn house since last fall. His building is similar to ours (a gambrel) with a smaller footprint of 2880 square feet. Upstairs will be a 1440 square foot living quarters. The downstairs is to be used strictly for the owner’s vehicles.
Should be easy, right?
I (as well as most of the post frame industry) have had little direct involvement with residential post frame. Here the Building Official is giving me a free lesson:
“….. forwarded me your email to help explain to you what is going on with the barn with dwelling above as noted below in your email. The size/area of the overall structure kicks the entire structure into the 2012 IBC for review. As you know the R-3 fire area kicks the entire building into the sprinkler system requirements as noted in section 903.2.8 of the 2012 IBC. The character size/area and use of the barn/garage area within the structure lends itself to the S-2 classification except that it is private use and not commercial use. Thus locally we have determined to leave such areas classified as group U occupancies while having them meet the requirements of the S-2 occupancy. This being said, you need to look at foot note b of Table 508.4 in the 2012 IBC which states; The required separation from areas used only for private or pleasure vehicles shall be reduced by 1-hour but to not less than 1-hour.
Due to the possible mix of garage and barn type uses with these structures, the fuel loads in the unfortunate event of a fire can be extremely significant within the mixed barn/garage environment. Consider vehicles of varying types with fuel in their tanks, storage cans of fuel, paints, solvents of varying types, hay, straw, wood shavings or chips, etc.,. We would be well within the scope of the intent of the code to jump to an even higher hazard occupancy classification which would lead to not only a different type of sprinkler system but also maintaining a 2 to 3-hour separation between the occupancies within the structure. Locally we have decided to take the approach noted above in the first paragraph and allow the owners of such structures two options.
Option 1 is to divide up the occupancy areas within the structure with a 2-hour Fire Wall (as described in section 706) such that in the eyes of the code, we have two separate structures. The dwelling area may then be constructed under the IRC instead of the IBC. If the barn or garage area with the dwelling area removed is still over 3,000 square feet it would still fall under the IBC for review and meet the requirements needed for that review. If the garage/barn area left over from subtracting out the dwelling area is less than 3,000 square feet, it too may be constructed under the 2012 IRC as an accessory structure. Again, once the true 2-hour Fire Wall exists the code will allow us to look at each one as a separate structure. The key here is it must be a true Fire Wall type separation and not a Fire Barrier. Considering horizontal fire wall assemblies, there is some justification to make them 3-hour instead of 2-hour so that they serve their intended purpose in the best of ways. We have not gone to the 3-hour on horizontal fire wall assemblies at this point.
Option 2 is to fully sprinkle the structure and provide the “not less than 1-hour” fire separation between the occupancies concerned (see leading paragraph notes). The local Fire Department having jurisdiction would need to review the structure being sprinkled to decide which type of sprinkler system is needed for proper structure protection.“
Due to the versatility of post frame buildings, we will see some very complex structures, with an entirely new challenges to be faced. A pole barn house is extremely efficient, functional, not to mention affordable at a lesser cost than stick built. It is a brave new world we are entering!