Table R301.2 of Chapter 3 of the 2022 Edition of the California Residential Code, is hereby amended to read as follows:
TABLE R301.2
CLIMATIC AND GEOGRAPHIC DESIGN CRITERIA
GROUND SNOW LOAD o | WIND DESIGN | SEISMIC DESIGN CATEG ORYf | SUBJECT TO DAMAGE FROM | ICE BARRIER UNDER- LAYME NT REQUIREDh | FLOOD HAZA RDSg | AIR FREEZ ING INDE Xi | ANNU AL MEAN TEMPj | |||||
Speedd
(mph ) | Topographic effectsk | Speci al wind regionl | Windborne debris zonem | Weathe ringa | Frost line depthb | Termi tec | ||||||
0 | 106 | NO | NO | NO | D2 or E | Negligi ble | 12 in. | Very Heavy | NO | See Exhibit B | 0 | 60 |
MANUAL J DESIGN CRITERIAn
Elevation | Altitude correction factor e | Coincident wet bulb | Indoor winter design dry-bulb temperature | Indoor winter design dry bulb temperature | Outdoor winter design dry-bulb temperature | Heating temperature difference |
305 | 69 | 70 | 39 | 31 | ||
Latitude | Daily range | Indoor summer design relative humidity | Indoor summer design relative humidity | Indoor summer design dry-bulb temperature | Outdoor summer design dry-bulb temperature | Cooling temperature difference |
34 | 27 | 75 | 85 | 10 |
For SI: 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.
a. Where weathering requires a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of this code, the frost line depth strength required for wreathing shall govern. The weathering column shall be filled in with the weathering index, “negligible”, “moderate" or “severe'’ for concrete as determined from Figure R301.2(1). The grade of masonry units shall be determined from ASTM C34, ASTM C55, ASTM C62, ASTM C73, ASTM C90, ASTM C129, ASTM C145, ASTM C216 or ASTM C652.
b. Where the frost line depth requires deeper footings than indicated in Figure R403.1(1), the frost line depth strength required for weathering shall govern. The jurisdiction shall fill in the frost line depth column with the minimum depth of footing below finish grade.
c. The jurisdiction shall fill in this part of the table to indicate the need for protection depending on whether there has been a history of local subterranean termite damage.
d. The jurisdiction shall fill in this part of the table with the wind speed from the basic wind speed map [Figure R301.2(2)]. Wind exposure category shall be determined on a site-specific basis in accordance with Section R301.2.1.4.
e. The jurisdiction shall fill in this section of the table to establish the design criteria using Table 10A from ACCA Manual J or established criteria determined by the jurisdiction.
f. The jurisdiction shall fill in this part of the table with the seismic design category determined from Section R301.2.2.1.
g. The jurisdiction shall fill in this part of the table with: the date of the jurisdiction’s entry into the National Flood Insurance Program (date of adoption of the first code or ordinance for management of flood hazard areas); and the title and date of the currently effective Flood Insurance Study or other flood hazard study and maps adopted by the authority having jurisdiction, as amended.
h. In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall fill in this part of the table with “NO."
i. The jurisdiction shall fill in this part of the table with the 100-year return period air freezing index (BF-days) from Figure R403.3(2) or from the 100-year (99 percent) value on the National Climatic Data Center data table “Air Freezing Index USA Method (Base 32°F).”
j. The jurisdiction shall fill in this part of the table with the mean annual temperature from the National Climatic Data Center data table “Air Freezing Index-USA Method (Base 32°F).”
k. In accordance with Section R301.2.1.5, where there is local historical data documenting structural damage to buildings due to topographic wind speed-up effects, the jurisdiction shall fill in this part of the table with “YES.” Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
l. In accordance with Figure R301.2(2), where there is local historical data documenting unusual wind conditions, the jurisdiction shall fill in this part of the table with "YES” and identify any specific requirements. Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
m. In accordance with Section R301.2.1.2 the jurisdiction shall indicate the wind-borne debris wind zone(s). Otherwise, the jurisdiction shall indicate “NO” in this part of the table.
n. The jurisdiction shall fill in these sections of the table to establish the design criteria using Table 1a or 1b from ACCA Manual J or established criteria determined by the jurisdiction.
o. The jurisdiction shall fill in this section of the table using the Ground Snow Loads in Figure R301.2(3) and R301.2(4).
(Ord. 3316 § 2 (part), 2022)