New Mexico design help

[ars001]

Just got off the phone with the plan reviewer from New Mexico. Being from Minnesota we do very little work outside the Midwest. He informed me that they were in a D1 seismic zone. What does D1 mean? Also, he informed me that we needed to have 24" min footing coverage. Typically in MN we provide a reinforced foundation wall down to a strip footing. Is this practice acceptable in New Mexico? Thanks for all your help.

 

[Bagman2524]

D1 is probably a Uniform Building Code (UBC) or possibly a IBC designation. I think New Mexico is a fairly low seismic area. IBC has designations of A through F. With F being the worst.

 

[JedClampett]

It sounds like some bad communication. Maybe he means that the soils are all seismic class D. As far as the footings, I don't think NM is any different than AZ, where I work. I'd call him (her) again, be non-confrontational, and ask what sections of the code they're referencing.

 

[OldPaperMaker]

ars001,
I think that the building official is giving you the seismic zone, D1 from the International Residential Code (IRC). The International Building Code (IBC)uses the mapped spectral accelerations, S sub s & S sub 1 (from the NOAA web site) to calculate S sub DS & S sub D1. These numbers are used to find the Base Shear, V from formulas 12.8-1 thru 12.8-6 of ASCE 7-05 (and E).
I don't use the IRC but I think that it is used mostly by non-engineers that do "precriptive design" of light framed buildings. Most engineers in the west do "rational design" and use the IBC.

I Hope that this helps.