Zone 2BHot (Zone 2)

Climate Zone 2B - Hot, Dry

Hot summers with low humidity. Moderate heating needs with large temperature swings. This climate zone encompasses parts of Arizona, California, Nevada, New Mexico, Texas and includes major cities like Albuquerque, El Paso, Bakersfield, Reno.

Common Questions About Zone 2B

Zone 2B definition

This page explains what IECC climate zone 2B means in HVAC and building-code terms.

Cities in zone 2B

Use the city examples below to answer common lookup searches for this zone.

Heating and cooling profile

See whether zone 2B is heating-dominant, cooling-dominant, or balanced.

HVAC requirements

Compare design temperatures, degree days, code requirements, and equipment guidance for this zone.

What IECC Climate Zone 2B Means

Temperature class

Hot (Zone 2)

Moisture class

Dry (B)

Load priority

Balanced heating and cooling

Quick definition

Hot summers with low humidity. Moderate heating needs with large temperature swings.

Common City Lookups for Zone 2B

CityIECC zone answerWhy it matters
AlbuquerqueAlbuquerque is commonly treated as IECC climate zone 2B in this guide.High cooling loads
El PasoEl Paso is commonly treated as IECC climate zone 2B in this guide.High cooling loads
BakersfieldBakersfield is commonly treated as IECC climate zone 2B in this guide.High cooling loads
RenoReno is commonly treated as IECC climate zone 2B in this guide.High cooling loads
FlagstaffFlagstaff is commonly treated as IECC climate zone 2B in this guide.High cooling loads

Design Temperatures

Winter Design Temperatures

20°F to 35°F

Used for heating load calculations and equipment sizing

Summer Design Temperatures

95°F to 105°F

Used for cooling load calculations and equipment sizing

Heating & Cooling Degree Days

Heating Degree Days (HDD)

2,000 - 4,000

Base 65°F. Higher numbers indicate more heating requirements and longer heating seasons.

Cooling Degree Days (CDD)

2,000 - 4,500

Base 65°F. Higher numbers indicate more cooling requirements and longer cooling seasons.

HVAC System Considerations

Key Considerations

  • High cooling loads
  • Moderate heating needs
  • Large diurnal temperature swings
  • Dust and UV protection
  • Low humidity year-round

Common Equipment

  • Heat pumps
  • Evaporative cooling in appropriate areas
  • Two-stage systems
  • Gas furnaces with AC

Energy Code Requirements

Equipment Efficiency

  • SEER 13+ minimum
  • HSPF 7.7+ for heat pumps
  • Radiant barriers
  • Window solar heat gain limits

Insulation Requirements

Walls:R-13 to R-19
Ceiling:R-30 to R-38
Floor:R-13 to R-19

Quick Reference

Zone:2B
Temperature:Hot
Moisture:Dry (B)
States:5
Cities:5

Calculate Load

Use our load calculators with the design temperatures and requirements specific to Zone 2B.