Rhode Island Climate Zones by County
All five of Rhode Island's counties are in climate zone 5A under the 2021 International Energy Conservation Code (IECC).
Insulation minimums in Rhode Island (zone 5A)
| Zone | Attic | Wood-frame walls | Floors over unheated space | Basement walls |
|---|---|---|---|---|
| 5A | R-60 | R-30, or 20+5ci, or 13+10ci, or R-20ci | R-30 | R-15ci, or R-19, or 13+5ci |
Minimums from the 2021 IECC (Table R402.1.3). Many areas still enforce an older edition, so check with your local building department. See sources.
Which energy code Rhode Island uses
Rhode Island enforces the 2024 IECC for homes (in effect since Dec 2025). Source: US Department of Energy, September 2026. Local governments can adopt newer codes or amendments. See every state's energy code.
What changed from the 2018 map
None of Rhode Island's counties changed zone between the 2018 and 2021 maps.
Every county in Rhode Island
| Name | Zone (2021) | Zone (2018) | Details |
|---|---|---|---|
| Bristol County | 5A | 5A | Insulation → |
| Kent County | 5A | 5A | Insulation → |
| Newport County | 5A | 5A | Insulation → |
| Providence County | 5A | 5A | Insulation → |
| Washington County | 5A | 5A | Insulation → |
Source: Pacific Northwest National Laboratory, Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates (2022).
Frequently asked questions
What climate zone is Rhode Island?
Rhode Island is IECC climate zone 5A under the 2021 code.
How much attic insulation do I need in Rhode Island?
The 2021 IECC calls for R-60 in the attic everywhere in Rhode Island.
What energy code does Rhode Island use?
Rhode Island enforces the 2024 IECC for homes (in effect since Dec 2025). Source: US Department of Energy, September 2026. Local governments can adopt newer codes or amendments.
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