The project I have been working has suffered a minor setback. These type things are to be expected when working in a new location. The drawings called for a new electrical drop to the ADU, but the city does not permit it to have it own drop. In order to have separate meters to the two homes another meter must be added to the existing unit and then the lines ran to the new ADUs location where an electrical panel may be installed. Along the wall the gas and water were also ran and their stub ups are in place. The general rule is that utilities should be 2 feet apart. However, an electrical panel needs a penetration so the breakers can be switched on and off as need be.
Therefore, before you place the electrical panel you must answer a few questions. Do you want the panel to open to the exterior or interior? If you chose the exterior, you must choose a location in which there is a large enough break in the shear. If you chose the interior, you need a space where it will be less conspicuous. Back porches, pantries, laundry rooms and closets are popular spaces for these however if you choose the closet, you cannot hang clothes in front of it blocking it door. We are considering the closet but on a side wall without clothing or the master bath where A mirror could be hug to hide the door yet allow easy accessibility.
The next issue is how to run the conduit from the location of the new meter to the location where the power line will come into the ADU. The conduit needs to have less than three 90s in it to be able to pull the new wiring through. An LP box allows for a 90 degree turn but cannot be buried. My solution for this setback was to come out of the new meter box and then enter the crawlspace under the home. I ran the wiring through 1 ½ inch conduit in the floor joist and out the other wall. The two penetrations needed to be sealed quickly to prevent unwanted entry by pest and damage to the foundation. I used the LP box at this location. I have two 90s in the run from the new meter to this LP box and two 90s with a 45 bend in the run from the LP box to the new panel.
Where the conduit penetrates the trench for the new concrete, I also drove a copper grounding rod so Ill be able to connect it to the rebar once it placed. Rebar can be used as the grounding rod but for whatever reason when a contractor placed the new 200-amp panel on the existing unit he drove 2 rods and he connected a ground to the water line. I will use # 4 solid copper wire as my ground wire and Riverside requires that this connection be visible. A small access panel will permit this in the future.
The main point I am trying to talk about is not the method I used to chose a location for this new electrical panel, but to warn about not penetrating a shear wall. It is easy to see how that the columns and studs carry the compression load of the load bearing walls however it is the sheers walls that keeps the structure from blowing over from winds and or seismic forces. These walls require special nailing and to remove any section of their plywood or OSB weakens them and this calls for another one to be place if possible or a lot of strapping and nailing.
These are the types of thing insurance companies look for when a claim has been filed to see if someone else may be responsible for the claim.
Note: Images on this blog site are from a free source or taken by the author. No image or group of photos is intended to represent the people the author serves. The author does not care about Race (that is a politically correct term that he does not like because we are all of the same Race, the Human Race. He prefers the term ethnicity, color, religion, sex, gender, marital status, disability, genetic information, national origin, source of income, Veteran or military status, ancestry, citizenship, primary language or immigration status.) He is a service provider for all people. We will all rise together when we band together and help one another. Joseph Erwin is a Real Estate Broker, DRE # O2131799, and a CA general contractor # B 696662. He’s a member of the CRMLS and The East Valley Association of Realtors located in the Inland Empire region of Southern California.
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