I'm putting my plans together to finish the basement in my house, which I've been in for about three years.

For a bit of background, my house was built in 1973 and previously had a finished basement. Due to some debacle with an in-ground pool, the basement flooded at one time and was therefore ripped apart and "de-finished". However, much of the electrical is still in place and functional.

Now, the previously finished bathroom only had a 15-amp breaker, but my understanding is that current code requires a 20-amp breaker. However, my circuit panel does not currently have an available 20 amp breaker. My panel sits at the back corner of a room with a finished ceiling, meaning that installing a new breaker and running cable would require (I assume) tearing out some of the ceiling.

I'm pulling all of the necessary permits and getting the inspections for this basement project. For existing construction like this, is there typically some leeway with these sorts of things? Will I be permitted to use the 15-amp breakers and cabling that exists, or will I be required to bring everything up to code?

 

As with all things, it's up to the local inspector, but my interpretation of code is that you would need to install a new 20A circuit for your bathroom.

 

I agree with Ben. Since you're building basically a new bathroom (or renovating it), you'll need to bring everything up to current code. That includes a dedicated 20A GFI circuit/receptacle.

If you were just replacing the toilet and/or vanity, there would probably be an exception, but not with the amount of work you'll be doing.

 

Ok, thanks for the replies.

In the case of an existing, finished ceiling, it is permissible to run new cable through the ceiling without needing to secure it every 4.5 feet, or will the new cable run require me to rip out the ceiling?

Alternatively, there is an unused 30-amp outlet in the laundry room adjacent to this bathroom. Previously this was used for the dryer, but the current dryer runs on gas. Is it possible to make use of this cable run (I don't know the gauge of the wire offhand) and convert it to a 20-amp circuit?

 

You do not have to fasten cables when fished through finished walls & ceilings. You may be able to repurpose the dryer circuit, but we'd need to know the gauge, material and number of conductors in the cable.

 

That probably wouldn't work. Most likely a 1973 vintage dryer circuit was installed with 10-3 Plain meaning there is no grounding conductor you would need to convert it to a 120 volt circuit. Back then NM cable (aka Romex) was available either with or without a ground wire and dryers typically were installed with 10-3 Plain just as range circuits were installed with 8-3 Plain or 6-3 Plain. Today ALL NM cable comes with a ground wire.

 

Thanks for all of the input.

After some further thought, I think I'll just have a new 20-amp circuit installed. I mapped out all of the existing wiring in the basement, and all outlets throughout the living area are also on 15-amp circuits with 14-gauge. I'd like to have all outlets on 20-amp, so I'll probably just run completely new 12-gauge wire through all the new basement outlets, fish that wire back to the panel, then have a pro come in and swap out the old 15-amp breakers and hook up the new wires to new 20-amp breakers.

My biggest concern was the possibility of needing to tear out ceiling to secure new wires, but if that's not typically required, then the rest of this should be cake.

 

The wiring needs to be secure and protected. You secure it where it's exposed.
Thru the ceiling is considered protected.