How to Read Electrical Blue Prints

Reading electrical blueprints is an acquired skill that becomes easier with practice.

Reading and understanding electrical blueprints takes practice. The plans are usually included with the normal architectural blueprints as a separate sheet. This allows the electrician to focus on the specifics of the electrical system without being distracted by the overall design and other elements included in the architectural blueprint. Most sets of blueprints also are provided with a specifications manual which includes notes and other information important to the project, but not included on the electrical blueprints themselves. All blueprints include legends that define the various symbols used in the plans.

Things You'll Need

• Specifications manual

Instructions

1. Review the architectural blueprints to gain an understanding of the layout and use of space for the building project. Knowing how the rooms are designed will make visualizing the electrical needs of the area clearer. Use the electrical blueprints as an overlay if possible. This will make reviewing both sets of plans at the same time much easier.

2. Study the blueprint's legend. The legend provides clear definitions of the symbols being used in the electrical blueprint. The legend is most often found on Page 1 of the electrical blueprints or the title page of the plans. An additional copy might also be provided in the specifications manual.

3. Review the wiring diagrams. These show the paths between the various outlets, switches, boxes and breaker panels. Most diagrams include numbers which indicate the circuit on which the various groups of wire are run. This helps clarify how lights and outlets are grouped and which circuits they belong to. This type of grouping is referred to as phasing.

4. Look at the lighting diagram to identify the type of lighting being used. The symbols are defined in the legend. Some projects may include the lighting diagram as a separate document.

5. Read the specifications manual if available. This manual might contain important information regarding the electrical blueprints that might or might not be reflected on the actual blueprints. The specifications manual will include the specific electrical requirements and the building materials required for the project.

Tips & Warnings

• Use a qualified electrician whenever possible to avoid future problems and potentially dangerous accidents resulting from faulty wiring.

References

• The House Designers: Understanding Blueprints
• Make My Own House: All Blueprint Symbols for Homebuilders
• Make My Own House: Diagram Electrical Wiring

Resources

• The House Plans Guide: Electrical Blueprints Symbols Glossary