For home wiring, solid copper wire is the standard choice for typical branch circuits in walls, while stranded copper wire, made of many thin strands, is more flexible and used where flexibility or larger sizes make it preferable. Both carry current well, but their construction suits different uses. Solid is common for the fixed wiring behind your walls and at outlets and switches, while stranded appears in appliance cords, some larger conductors, and flexible applications. Understanding the difference helps explain why each is used where it is.

Here is how stranded and solid copper wire compare for home wiring.

The basic difference

The difference is in construction. Solid wire is a single solid conductor, while stranded wire is made of many thin strands bundled together into one conductor. Both are copper and carry current, but solid is stiffer and holds its shape, while stranded is more flexible and bends more easily. This difference in flexibility and handling is what drives where each is used.

Where solid wire is used

Solid copper wire is the standard for typical residential branch-circuit wiring, the fixed wiring in walls that feeds outlets, switches, and lights. In the common sizes used for home branch circuits, solid conductors are the norm, as in standard NM-B cable. Solid wire holds securely under screw terminals and is well suited to the fixed, concealed runs of a home’s wiring.

Where stranded wire is used

Stranded copper wire is used where flexibility matters or at larger sizes:

• Appliance and equipment cords, which need to flex
• Larger conductors, where stranding makes big wires manageable
• Applications needing flexibility, such as certain connections and equipment
• Some specific wiring methods where it is preferred

Stranded wire’s flexibility makes it the right choice for these uses, even though solid dominates fixed branch wiring.

Why solid is standard for branch circuits

Solid wire is standard for home branch circuits because it is well suited to fixed, concealed wiring and to the screw-terminal connections at outlets and switches, where it holds securely. For the common residential wire sizes, solid is practical and economical, and it is what most home wiring and NM cable use. This is why the wiring in your walls is typically solid copper.

Termination differences

One practical point is that solid and stranded wire are terminated somewhat differently. Solid wire loops neatly under a screw terminal, while stranded wire, with its many strands, may be handled with the correct terminal type or technique so all strands are captured securely. Using the right termination method for each is part of making sound connections, which is one reason wiring is best done by a licensed electrician who handles both correctly.

For home wiring, solid copper wire is the standard for typical branch circuits in walls, holding securely under screw terminals and suiting fixed, concealed runs, while stranded copper wire is more flexible and used for appliance cords, larger conductors, and flexible applications. Both carry current well, but their construction suits different uses. A licensed electrician uses the right type and termination for each application.

Stella Electric wires homes using the correct conductors and sound connections for homeowners across the Baltimore area and throughout Maryland, with flat-rate pricing and no overtime charges. If you need wiring done right, we handle the details. Financing is available on qualifying projects.