Table R301.1 shall be used in determining the applicable requirements from Chapter 4. Locations are assigned a climate zone based on Section R301.3.
Figure R301.1 Climate Zones.
CLIMATE ZONES, MOISTURE REGIMES AND WARM-HUMID DESIGNATIONS BY COUNTY
|Key: A – Moist |
Asterisk (*) indicates a warm-humid location.
|2A Indian River*|
|1A Palm Beach*|
|2A Santa Rosa*|
|2A St. Johns*|
|2A St. Lucie*|
The climate zone for any location outside the United States shall be determined by applying Table R301.3(1) and then Table R301.3(2).
INTERNATIONAL CLIMATE ZONE DEFINITIONS
|MAJOR CLIMATE TYPE DEFINITIONS|
|Marine (C) Definition—Locations meeting all four criteria: |
|Dry (B) Definition—Locations meeting the following criteria:|
|Not marine and Pin < 0.44 × (TF - 19.5) [Pcm < 2.0 × (TC + 7) in SI units]|
Pin = Annual precipitation in inches (cm)
T = Annual mean temperature in °F (°C)
|Moist (A) Definition—Locations that are not marine and not dry.|
|Warm-humid Definition—Moist (A) locations where either of the following wet-bulb temperature conditions shall occur during the warmest six consecutive months of the year: |
For SI: °C = [(°F)-32]/1.8, 1 inch = 2.54 cm.
INTERNATIONAL CLIMATE ZONE DEFINITIONS
|IP Units||SI Units|
|1||9000 < CDD50°F||5000 < CDD10°C|
|2||6300 < CDD50°F ≤ 9000||3500 < CDD10°C ≤ 5000|
|3A and 3B||4500 < CDD50°F ≤ 6300 AND HDD65°F ≤ 5400||2500 < CDD10°C ≤ 3500 AND HDD18°C ≤ 3000|
|4A and 4B||CDD50°F ≤ 4500 AND HDD65°F ≤ 5400||CDD10°C ≤ 2500 AND HDD18°C ≤ 3000|
|3C||HDD65°F ≤ 3600||HDD18°C ≤ 2000|
|4C||3600 < HDD65°F ≤ 5400||2000 < HDD18°C ≤ 3000|
|5||5400 < HDD65°F ≤ 7200||3000 < HDD18°C ≤ 4000|
|6||7200 < HDD65°F ≤ 9000||4000 < HDD18°C ≤ 5000|
|7||9000 < HDD65°F ≤ 12600||5000 < HDD18°C ≤ 7000|
|8||12600 < HDD65°F||7000 < HDD18°C|
For SI: °C = [(°F)-32]/1.8.
The tropical climate zone shall be defined as:
- Hawaii, Puerto Rico, Guam, American Samoa, U.S. Virgin Islands, Commonwealth of Northern Mariana Islands; and
- Islands in the area between the Tropic of Cancer and the Tropic of Capricorn.
R-values referenced in Chapter 4 of this code refer to the R-values of the added insulation only. The R-values of structural building materials such as framing members, concrete blocks or gypsum board shall not be included.
Exception: R402.1.5 Total UA Alternative.
U-factors of fenestration products (windows, doors and skylights) shall be determined in accordance with NFRC 100.
Exception: Where required, garage door U-factors shall be determined in accordance with either NFRC 100 or ANSI/DASMA 105.
U-factors shall be determined by an accredited, independent laboratory, and labeled and certified by the manufacturer.
Products lacking such a labeled U-factor shall be assigned a default U-factor from Table R303.1.3(1) or R303.1.3(2). The solar heat gain coefficient (SHGC) and visible transmittance (VT) of glazed fenestration products (windows, glazed doors and skylights) shall be determined in accordance with NFRC 200 by an accredited, independent laboratory, and labeled and certified by the manufacturer. Products lacking such a labeled SHGC or VT shall be assigned a default SHGC or VT from Table R303.1.3(3).
DEFAULT GLAZED FENESTRATION U-FACTORS
|FRAME TYPE||SINGLE |
|Metal with Thermal Break||1.10||0.65||1.90||1.10|
|Nonmetal or Metal Clad||0.95||0.55||1.75||1.05|
DEFAULT DOOR U-FACTORS
|Insulated, nonmetal edge, max 45% glazing, |
any glazing double pane
DEFAULT GLAZED FENESTRATION SHGC AND VT
|SINGLE GLAZED||DOUBLE GLAZED||GLAZED |
Insulation materials shall comply with the requirements of their respective ASTM standard specification and shall be installed in accordance with their respective ASTM installation practice in Table R303.2.1 in such a manner as to achieve rated R-value of insulation. Open-blown or poured loose-fill insulation shall not be used in attic roof spaces when the slope of the ceiling is more than 3 in 12. When eave vents are installed, baffling of the vent openings shall be provided to deflect the incoming air above the surface of the insulation.
Exception: Where metal building roof and metal building wall insulation is compressed between the roof or wall skin and the structure.
INSULATION INSTALLATION STANDARDS
|INSULATION MATERIAL||STANDARD SPECIFICATION||INSTALLATION PRACTICE|
|Mineral Fiber Batt/Blanket||ASTM C665||ASTM C1320|
|Mineral Fiber Loose Fill||ASTM C764||ASTM C1015|
|Cellulose Loose Fill||ASTM C739||ASTM C1015|
|Polystyrene Foam||ASTM C578||—|
|Polyisocyanurate Foam||ASTM C1289||—|
|Reflective||ASTM C1224||ASTM C727|
|Radiant Barrier||ASTM C1313||ASTM C1158|
|Spray-applied Rigid Cellular Polyurethane Foam||ASTM C1029||—|
|Interior Radiation Control Coating Systems||—||ASTM C1321|
Insulation that has been compressed to 85 percent or less of the manufacturer’s rated thickness for the product shall use the R-values given in Table 303.2.1.1. These values are to be used except where data developed by an independent testing laboratory are provided.
R-VALUES OF COMPRESSED INSULATION
|% OF ORIGINAL THICKNESS||R-5||R-7||R-11||R-14||R-19||R-30||R-38|
Insulation shall be installed in a permanent manner in substantial contact with the inside surface in accordance with manufacturer’s recommendations for the framing system used. Flexible batt insulation installed in floor cavities shall be supported in a permanent manner by supports no greater than 24 inches (610 mm) on center (o.c.).
Exception: Insulation materials that rely on airspaces adjacent to reflective surfaces for their rated performance.