Speaker Wire in Wall Code: The Rules the Run Follows

Quick answer / TL;DR: The speaker wire in wall code runs the line on the Class 2 circuit – the power-limited low voltage the speaker output occupies – through the listed stock the concealed path requires, the CMR jacket for the wall's cavity and the plenum-rated line for the air-handling space. The rules cover the jacket's listing, the route through the structure, the separation from the power conductors, the firestopping where a rated assembly is crossed, and the local amendments the authority having jurisdiction reads. The inspector checks the jacket's print and the route at the rough-in, before the drywall closes.

The speaker wire in wall code is the set of rules the concealed run follows, and the rules start with the circuit the wire occupies. The speaker line is the low-voltage output the Class 2 circuit carries – the power-limited classification the code's protection rules are written around – and the jacket the run uses is the listed stock the concealed path allows. The code's interest is the fire's behavior in the wall's cavity and the circuit's safety, and the figures it reads are the jacket's print, the run's route and the separation the power conductors take.

This is the code's view: the circuit class the run sits in, the listed jacket the concealed path requires, the routing and separation the rules state, and the checks the inspector makes at the wall before the drywall closes.

The Circuit, and the Code's First Figure

The code's first figure is the circuit class, and the speaker line is the Class 2 case. The amplifier's output is the low voltage the classification covers – the power-limited circuit under the figures that call for the protection the branch circuit takes – and the classification is what the run's rule set is written around. The Class 2 circuit is exempt from the conduit and the overcurrent device the building wire needs, and the exemption is the reason the speaker run can travel the wall's cavity on the jacket's listing alone. The circuit class is the figure the rest of the code's rules inherit: the jacket the path requires, the separation the power conductors take, and the protection the run does not need because the circuit's energy is limited.

The table is the code's figures, and the reading is where each one lands on the run. The circuit class is the output's figure, the listing is the jacket's, and the route and the separation are the path's – the stud bay the run dresses and the crossing the power conductors take. The firestopping is the structure's figure, the rated assembly the run crosses and the seal the penetration needs. Five figures, and the speaker wire in wall code is the run that answers all five at the wall the drywall is about to cover.

The Listing, by the Path

The listing is the jacket's figure, and the code reads it by the path the run takes. The wall's cavity – the stud bay the drywall covers, the joist space the ceiling's structure encloses – is the path the CMR stock serves, the communication wire's listing for the master and riser circuit. The air-handling space – the plenum the HVAC system's return air crosses, the ceiling the building's air moves through – is the path the plenum-rated stock serves, the listing above the CMR for the air the building breathes. The floor's bay and the surface conduit are the path's other forms, and the listing the code reads is the one the path states. The jacket's print is the figure the inspector reads at the rough-in, and the listing by the path is the first check the run passes.

The plenum, and the line above the CMR

The plenum is the path the CMR does not serve, and the figure is the air the space moves. The air-handling space – the ceiling's return plenum, the duct's chase, the space the building's air crosses – is the path the plenum-rated stock carries, the listing the jacket's material holds for the smoke and the flame the air would carry. The CMR stock is the wall's cavity's wire, and the plenum rating is the line above it for the space the air moves through. The run that crosses the air-handling space is the one the plenum stock serves, and the code's reading of the path's figure is the check the inspector makes before the ceiling closes.

The Route, the Separation, and the Firestopping

The route and the separation are the path's figures, and the code reads them at the run's dress. The route is the stud bay, the joist space, the bay the structure's framing leaves – the path the run dresses through the cavity rather than the notch the structure's member would take, the drilling's rules the framing's spans carry. The separation is the distance from the power conductors, the figure the code's rules for the low-voltage circuit state and the practical one the hum's coupling makes necessary – the parallel run's distance and the crossing's right angle. The firestopping is the structure's figure: the rated assembly the run crosses – the fire-rated wall, the floor's assembly – and the seal the penetration takes to keep the assembly's rating. Three figures, and the run that dresses the route, keeps the separation and seals the penetration is the one the code's reading passes.

The separation, and the figure the hum adds

The separation's code figure is the one the low-voltage rules state, and the practical figure is the hum the power's field writes into the run. The speaker line's low voltage reads the write the power conductors' field puts into the loop the pair presents, and the parallel run beside the power is the one the field gathers at the distance the separation's figure sets. The crossing at the right angle is the practical move the run makes where the separation cannot hold, and the distance the rules state is the one the code and the hum's coupling both read. The separation is the code's figure and the audio's, and the run that holds it is the one the wall's cavity is quiet at after the drywall closes.

The Inspector's Check, and the Local Reading

The inspector's check is the reading the run passes before the drywall closes, and the figures are the jacket's print, the route and the separation. The print is the listing the path requires, read along the wire the cavity holds. The route is the stud bay and the joist space the run dresses, and the separation is the distance the power conductors take. The firestopping is the seal the rated assembly's penetration carries. The local reading is the authority's – the amendments the jurisdiction makes to the code's figures – and the check at the rough-in is the minute the run's compliance is confirmed rather than discovered. The code's figures are the ones the run answers, and the rough-in's check is the stage the answers are read at.

The in wall speaker wire the code's figures are read on is stocked as the CMR-rated line for the wall's cavity and the plenum-rated stock for the air-handling space, in the gauge range; the catalog lists the rating, the gauge and the length per roll, and the authority having jurisdiction's amendments are the figures the local install confirms.

Real-World Applications

The new build's rough-in: the CMR stock through the stud bays, the separation from the power's runs held, the firestopping at the rated wall, and the inspector's print check before the drywall. The office's ceiling: the plenum stock through the air-handling space, the listing above the CMR the path required, and the ceiling's closure the check preceded. The retrofit's route: the joist space the run dresses, the crossing at the right angle where the separation could not hold, and the seal the rated assembly's penetration took. In each the speaker wire in wall code is the run's answer to the five figures – the Class 2 circuit, the jacket's listing, the route, the separation and the firestopping – and the rough-in's check is the stage the wall's cavity reads them at.

Related reading: The jacket the code's listing reads, in full: what is in wall speaker wire — what-is-in-wall-speaker-wire

Related reading: The separation figure, and the hum it prevents: speaker wire next to electrical wire — speaker-wire-next-to-electrical

Frequently Asked Questions

What code applies to speaker wire in the wall?

The concealed run follows the electrical code's rules for the circuit and the building's rules for the space: the speaker line's low voltage puts it in the Class 2 classification, the concealed path requires the listed jacket – the CMR stock for the wall's cavity, the plenum rating for the air-handling space – and the route, the separation from the power conductors and the firestopping at the rated assembly are the path's figures. The local authority's amendments are the figures the specific jurisdiction reads, and the rough-in's inspection is the stage the run is checked.

Does speaker wire in the wall need to be in conduit?

The Class 2 circuit is the exemption – the power-limited line the low-voltage classification covers, and the conduit the building wire's protection requires is not the speaker run's figure. The jacket's listing is what the concealed path reads, and the listing is the wire's own rating rather than the conduit's protection. The local code's amendments are the figures the specific jurisdiction states, and the inspection at the rough-in is the check the run's answer is read at.

Can speaker wire run next to electrical wire in the wall?

The code's separation figure is the distance the low-voltage rules state, and the practical figure is the hum the power's field writes into the run. The parallel run beside the power is the one the field gathers, and the crossing at the right angle is the move where the distance cannot hold. The separation the rules state and the coupling the audio reads are the two figures the run's route holds, and the wall's cavity is the space the separation is dressed in.

What is the plenum rating, and when do I need it?

The listing above the CMR for the air-handling space – the ceiling's return plenum, the duct's chase, the space the building's air crosses. The plenum stock's jacket is rated for the smoke and the flame the air would carry, and the path the air moves through is the one the rating serves. The wall's cavity is the CMR's path, and the air-handling space is the plenum's – the code's listing by the path, and the run's route is the figure that states which.

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