Okay, I understand the situation. You have a builder wanting the receptacle installed on the mirror (deviating from the plan), but you're concerned about the proximity to the shower stall and the interpretation of the electrical code by a 3rd-party inspector who tends to be overly strict.Here's a breakdown of the code requirements, your concerns, and my recommendations

1. NEC (National Electrical Code) Concerns:
Receptacle Proximity to Shower

The primary concern is the requirement regarding receptacle placement near tubs and showers. While the specific wording of the NEC can vary slightly between editions (depending on the year your 3rd party is using) a common rule is that receptacles must not be located within a zone that extends 3 feet horizontally and 8 feet vertically from the top of the tub rim or shower threshold.

Defining the Zone

This is where interpretation comes into play. The 3-foot horizontal measurement originates from the edge of the tub or shower stall threshold.

The "Fixed Barrier" Exception

This is the crux of your argument and the point of potential conflict with the inspector. The NEC might allow for an exception if a fixed barrier exists. The key is whether the glass shower enclosure (which doesn't reach the ceiling) is considered a "fixed barrier" by the inspector.

2. Why Installing on the Mirror is Problematic



Violation of Plan

The most straightforward issue is that it deviates from the approved plan. If the plan specified the wall, changing it to the mirror without approval is a problem in itself, especially with 3rd-party inspections involved.

Safety

Mirrors in bathrooms are prone to condensation and moisture. Installing an electrical receptacle directly on a mirror increases the risk of water intrusion and potential electrical hazards.

Serviceability

Replacing or repairing a receptacle on a mirror can be more difficult and potentially damaging to the mirror compared to a wall-mounted receptacle.

Aesthetics

While subjective, many people find receptacles mounted on mirrors visually unappealing.

3. Analyzing the "Fixed Barrier" Argument



The Inspector's Interpretation is Key

Ultimately, whether the glass enclosure qualifies as a "fixed barrier" rests on the inspector's interpretation. Because these 3rd party inspectors have made up their own rules, this is paramount.

Arguments Against "Fixed Barrier"



Incomplete Enclosure

The fact that the glass doesn't reach the ceiling is a strong argument against it being a "fixed barrier." Moisture and splashing can easily travel over the top of the glass and reach the receptacle.

Not Fully Sealed

Even if the glass reached the ceiling, if it's not perfectly sealed, it might still not be considered a barrier.

Arguments For "Fixed Barrier" (Weaker)



Deflection of Water

You could argue that the glass effectively deflects the majority of water spray.

Local Practice

If it's common practice in your area to consider similar glass enclosures as barriers, you might have a chance.

4. Recommendations



Install on the Wall per Plan (Recommended)

This is your best course of action. It avoids the mirror-mounting issues, adheres to the plan, and minimizes the risk of conflict with the inspector. Installing to the plans and specs is always the safest route.

Document Everything

Keep detailed records of all communications, inspector interpretations, and code references. This will be valuable if you need to appeal or defend your installation.

Communication with the 3rd-Party Inspector



Before Installation

If possible, contact the 3rd-party inspector before installing the receptacle. Ask them specifically if they would consider the glass shower enclosure (with its dimensions) a "fixed barrier" that would allow a receptacle closer than 3 feet. Get their answer in writing (email).

During Inspection

Be prepared to explain your reasoning and provide code references if the inspector raises concerns.

Offer Alternatives (If Necessary)



GFCI Protection

If the inspector is hesitant, emphasize that the circuit is GFCI protected, which provides an extra layer of safety.

Move the Receptacle

If the wall isn't fixed, offer to move the receptacle slightly further away from the shower stall if there's room, even if it means a minor change to the plan. Sometimes a small compromise can satisfy the inspector.

Appeal if Necessary

If the inspector rejects your installation despite your best efforts, inquire about the appeals process.

In summary: While a strictly technical argument might* be made for the glass acting as a barrier, it's a weak argument given the incomplete enclosure. The best course of action is to install the receptacle on the wall according to the plan. Communicate with the inspector beforehand if possible, and be prepared to defend your installation. Don't install it on the mirror – it's a bad idea for multiple reasons. Flag for review