How to Draw an Electrical Plan of Your House, Online

What an electrical plan is for

An electrical plan is a floor plan with the electrical equipment drawn on it: the panel, the outlets, the switches, the lights and the runs of cable between them. Its first use is a conversation. A contractor who has your drawing can quote on the same list as the next contractor, and you can compare the bids line by line instead of guessing what each one includes.

Its second use is thinking. Drawn before the work, the plan shows the room where there are too few outlets, the long run from the panel to the garage, the circuit that will carry the whole kitchen. Moving an outlet on paper costs a click, and moving it behind a finished wall costs a day.

It also keeps a record. A drawing of where the cables run is worth having years later, when someone wants to hang a shelf or open a wall.

Before you draw: the base and the rules

Start from an accurate floor plan, because the cable lengths and the position of every device depend on it. If you do not have one yet, draw the structure first, as the guide to drawing a house plan explains: walls at their real thickness, openings, rooms. The electrical layer sits on top of that.

Then find out which rules apply to you. In the United States, residential wiring follows the National Electrical Code (NFPA 70), together with the amendments each state, county or city adds, and work usually needs a permit and an inspection through your local building department. Which jobs a homeowner may do, and which need a licensed electrician, depends on where you live. Check with your building department before you start.

The method: from the walls to the circuits

1. Draw the structure first

   Draw the outside walls, the inside walls, the doors and the windows, and name the rooms. The cables follow the walls, so the base must be right before you add anything to it.

2. Switch to Electricity mode

   Open Layers and choose Electricity. A mode locks the other layers, so you cannot move a wall by accident while placing outlets, and you can still show or hide the layers you want to see.

3. Place the breaker panel

   Put the breaker panel where it really is, or where you want it. The electric meter is in the library too. The panel is the starting point of every circuit, and its position decides the length of every run.

4. Place the outlets, switches and lights

   The Electricity family of the library has outlets (single, double, high-power, weatherproof, TV and network), switches (single and two-way), ceiling lights and wall lights. Pick one, then click the plan. On a phone, place it with the viewfinder: drag the plan under the crosshair and tap Place.

5. Lay the cables

   Draw each cable as a run by tapping points from the panel to the devices it feeds, and finish the run. If the house has more than one floor, a riser joins two floors, so the cable length accounts for the climb.

6. Make the circuits

   Create a circuit for each run. Give it a name and a use (outlets, lighting or dedicated), a breaker, a cable gauge and a color, so you can tell the circuits apart on the plan. A dedicated circuit feeds one appliance only: the range, the dryer, the water heater.

7. Read the advice and the cable lengths

   Plan² shows the length of cable of every circuit, and the advice flags the circuits that look overloaded or mixed up. Treat the advice as described above: a prompt to look again, not a verdict. Fix what is a slip, and note what your electrician should decide.

8. Export with the legend and measure

   Choose File, then Export…, pick the plan type, a PNG or PDF, the paper and the scale from 1:50 to 1:500, and choose which networks to include: over the plan, under it, or apart, with one plan per network. Switch on the legend and measure to print the circuits and their cable lengths. The PDF is vector at true scale.

Good habits when you plan the circuits

These are general habits, not code requirements. Your code and your electrician have the final word.

• Keep circuits short and simple: one that wanders through five rooms is harder to understand, to repair and to extend.
• Do not put the whole house on a few circuits: split lighting from outlets, and keep a separate circuit for each large appliance.
• Group devices by area as well as by use, so that shutting a breaker to work on one room does not turn off the whole floor.
• Think about future needs: a charger in the garage, a workshop, a home office. A spare breaker space costs less than a new panel.
• Place the switches where a hand looks for them, beside the door, on the side of the handle.
• Leave room around the panel: it must stay reachable, and the clearance in front of it is set by your code.

Common mistakes in an electrical plan

• Drawing devices before the walls are right, then moving everything.
• Putting every outlet of a kitchen on a single circuit.
• Forgetting the cable runs between floors, which are the longest.
• Reading the Plan² advice as a verdict: it is a French-based hint, not a check under your code.
• Skipping the legend: without the circuit names and lengths, the electrician has to start over.
• Treating the plan as a permit drawing, when the permit and the inspection go through your building department.

What Plan² does not do

Plan² does not size a circuit, check a drawing against the NEC or any other code, or replace an electrician or an inspection. Its advice is indicative. It does not draw wiring diagrams or panel schedules, and it does not draw sections, elevations or heights, which are coming. What it does is give you a clear drawing of where everything goes, circuit by circuit, with the cable lengths worked out, which is what a contractor needs to quote.