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How to calculate a range in a dwelling load calculation (220.55)
Ranges are one of the trickiest parts of a whole-house load calculation. Lesson 3.2 walks through the demand table. Note: in the 2026 NEC, Article 220's dwelling load calcs moved to Article 120, so 220.55 is now 120.55.
The breakdown, in plain English
- You don't add the nameplate rating of a range straight in. You use the demand table, which allows less than the nameplate because ranges rarely run everything at once.
- One range rated 12 kW or less: use 8 kW (Column C).
- Over 12 kW: add 5% to that 8 kW for every kW (or major fraction) above 12.
- Smaller cooking appliances can use the lower columns of the table instead. Read the table notes carefully, because the exam loves them.
Worked example
Example: one 14 kW range
- 14 kW − 12 kW = 2 kW over.
- 2 × 5% = 10% increase.
- 8 kW × 1.10 = 8.8 kW demand load.
Codes to look up
Household ranges and cooking appliances can use the demand factors in the table instead of their full nameplate rating.
For a range over 12 kW, increase the Column C value by 5% per kW above 12.
These are plain-English summaries, not the code's exact wording. Always check the full section in the NEC edition your area has adopted, plus local amendments.
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