Practice: dwelling standard load calculation
Each problem uses new numbers, so you practice the method rather than memorizing an answer.
Pick the answer: sizes and ratings come from your code book.
Worked solution
Formula
| Symbol | Meaning | Unit |
|---|---|---|
| A | Floor area from the outside dimensions (120.5(C)) | ft² |
| Lighting demand | General lighting, small-appliance and laundry load after Table 120.45 | VA |
| Total | Calculated service or feeder load | VA |
| I | Service load current at 240 V | A |
Worked example
A one-family dwelling has 3,600 ft² of living area, measured to the outside walls. It has 2 small-appliance branch circuits and one laundry circuit. Using the standard method, what is the demand load for general lighting and general-use receptacles plus the small-appliance and laundry circuits?
- General lighting and general-use receptacles at 2 VA/ft² (120.41): 3,600 × 2 = 7,200 VA.
- Small-appliance and laundry circuits at 1,500 VA each (120.52): (2 + 1) × 1,500 = 4,500 VA.
- Total before demand factors: 7,200 + 4,500 = 11,700 VA.
- Look up Table 120.45: the first 3,000 VA is taken at 100% = 3,000 VA.
- The next 8,700 VA is taken at 35% = 3,045 VA.
- Demand load: 3,000 + 3,045 = 6,045 VA.
Answer: 6,045 VA
Dwelling standard load calculation, explained
The standard method is the default dwelling calculation. PSI tells Texas candidates not to use an optional method unless the question asks for it, so when a question just says "calculate the service", this is the method. In the 2026 NEC it is in Article 120, Part III. It was Article 220 in 2023, and most section numbers kept their last digits: 220.41 is now 120.41, 220.53 is now 120.53.
The biggest 2026 change is the unit load. Open 120.41: dwelling general lighting and general-use receptacles are now 2 VA/ft² for feeder and service calculations, down from 3 VA/ft². The 3 VA/ft² figure still exists, but only in 120.13 for counting how many general lighting branch circuits the house needs.
Work the groups in order. Lighting plus 1,500 VA for each small-appliance and laundry circuit (120.52) goes through Table 120.45. Fastened appliances such as the water heater, dishwasher, disposal and microwave take 75% when there are four or more (120.53). The dryer counts at the larger of 5,000 W or its nameplate (120.54). One range of 12 kW or less counts 8 kW from Table 120.55, Column C. Heat and AC never run together, so 120.6 lets you keep only the larger.
Add the groups and divide by 240 V for a 120/240 V service. The result is the minimum load the service must carry; the next step on a real job is picking the service rating and conductors from it.
How to solve it on the exam
- Find the area from the outside dimensions. Multiply by 2 VA/ft² (120.41) and add 1,500 VA for each small-appliance and laundry circuit (120.52).
- Apply Table 120.45 to that subtotal: first 3,000 VA at 100%, the rest at 35%.
- Add the fastened-in-place appliances. If there are four or more, take 75% (120.53). Do not count the range, dryer, heat, AC or EV charger here.
- Add the dryer at the larger of 5,000 W or nameplate (120.54) and the range from Table 120.55 (8 kW for one range of 12 kW or less).
- Compare heat and AC and add only the larger (120.6). Add everything and divide by 240 V.
Common mistakes
- Using 3 VA/ft² for the service calculation. That was the 2023 rule. In 2026 it is 2 VA/ft² (120.41); 3 VA/ft² is only for counting branch circuits (120.13).
- Forgetting the laundry circuit, or using only two small-appliance circuits when the question gives three.
- Putting the dryer or range in the 75% appliance group. They have their own rules in 120.54 and 120.55.
- Using the range nameplate instead of Column C, or the dryer nameplate when it is under 5,000 W.
- Adding both heat and AC. Only the larger counts (120.6).
- Dividing by 120 V instead of 240 V for a 120/240 V service.
Exam tips
- Older prep books and many websites still show 3 VA/ft². If an answer choice matches a 3 VA/ft² calculation, it is the trap for 2023-trained students.
- Tab Article 120 in your 2026 code book: 120.41, Table 120.45, 120.53, 120.54 and Table 120.55 are all within a few pages.
- Write the groups as a list on the notepad (lighting, appliances, dryer, range, heat or AC) and add them at the end. It keeps you from dropping a group under time pressure.
Dwelling standard load calculation calculator
Questions people ask
How many VA per square foot is a house in the 2026 NEC?
2 VA per square foot for feeder and service calculations (120.41). The 2023 NEC used 3 VA. The 3 VA figure is still used in 120.13 to count general lighting branch circuits.
Where did Article 220 go in the 2026 NEC?
Load calculations moved to Article 120. Most numbers kept their last digits, so 220.41 is now 120.41, Table 220.45 is Table 120.45 and 220.53 is 120.53. Noncoincident loads moved from 220.60 to 120.6.
Do I include both the heat and the air conditioner?
No. Heat and AC are noncoincident loads, so 120.6 lets you use only the larger of the two.
What range load do I use for one 12 kW range?
8 kW, from Table 120.55, Column C. A range over 12 kW gets 5% more for each kW over 12 (Note 1).
Sources
- TDLR: Electrician examination information
- PSI: Texas electrician Candidate Information Bulletin
- EC&M: Changes to dwelling unit calculations in the 2026 NEC
- Mike Holt: Electrical Exam Preparation, 2026 NEC, Unit 6 sample (free PDF)
- NFPA: 2026 NEC Second Draft report, Code-Making Panel 2 (Article 120)
About the tables: The exam is open book. These problems cite the 2026 NEC section and table so you practice finding them in your own book. We never print NEC text or tables.