Category: Low Voltage

Several years back I started planning for the home security system. Most home security these days has gone wireless, but I found myself leaning old school. The wireless sensors generally cost around $30 apiece, have batteries to replace, and are typically bulky and can lose their connection, leading to lack of coverage or false positives. Conversely, the wired sensors are cheap. That same $30 gets you a bag of ten window and door sensors. Plus, they’re tiny, able to be concealed within the jamb so they are invisible. There’s no batteries to replace, I can literally put a sensor on every single door and window and a motion sensor in every room, and I can integrate it with smart home functionality. With the house gutted, running the wires is still an undertaking, but it’s not terribly difficult.

My goal with the system is to tie these sensors into triggers and actions. If it starts raining or the temperature suddenly drops and I’ve left a window open, I get a notification on my phone. If it’s night time and someone walks into a hallway or stairwell, the lights can come up just a bit, but during the day they can turn all the way on or not come on at all, whichever makes more sense for a given space. As an actual security system, we can either have it remotely monitored by an inexpensive service, or have it send us a notification if we’re away and a door or window opens or a motion sensor is triggered.

So as I said, I started planning this years ago. I did some research, picked out a system, wound up buying all the components, and they sat in a box collecting dust (I just checked and it was 2014!). I decided to wait until after spray foam to run the wires, since they’re fairly low profile. In hindsight, that was probably a mistake, but I wanted to be able to access it later if I really needed to even if it meant cutting drywall. It’s just 18 gauge 2-wire thermostat wire, so I picked up a 500 foot spool and started drilling into all my windows and jambs. Fishing the wires through the 3/8″ holes is tricky, and figuring out the best way to get the wiring into the ceiling while avoiding studs as much as possible, since that’s where drywall screws are likely to go is its own process, but it really isn’t too bad.

I decided to put the panel in the laundry room closet. It’s relatively central to shorten wire lengths with easy access to the area behind the attic knee wall above where I can run wires from one end of the house to the other. Initially I’d planned to only have motion sensors in the common spaces, but I wound up getting some PIR motion sensors for the bedrooms as well so we could tie smart triggers based on occupancy status. About the time I finished the attic and second floor, I bought a second 500′ spool of wire. The first floor was fairly straightforward, since by this point I’d gotten familiar with the process.

I thought the basement was the last step in the process, with the added challenge of getting the wires through two floors worth. I kept getting pulled away from this to work on other projects, but I got the back window and door wires run before I had to pick up a third 500′ spool. I really underestimated how much wire this would take, plus the spools aren’t particularly cheap. Parts of the beam look positively festooned where I set up raceways for converging sensor wires.

After I was done with the basement and ready to shift gears, I realized I was missing a few things. First, I had picked up a water level sensor for the mechanical room to alert me to leaks. Ok, just a forgotten sensor, run another line, all set. Then I realized I didn’t have power to the panel. The system uses a transformer, which I didn’t want to plug into one of the two outlets in the laundry closet, since they’re obviously for the washer and dryer. So instead I ran another line clear down to the mechanical room for that. Finally, I realized I needed to run the ethernet cable for the smart home integration, since I don’t have easy access to one of my drops, so I ran that through the wall to where I can connect it to a switch.

Next steps on this project can wait. I have all the wiring done and that’s what I need to have finished for drywall. I’ll have to install the PIR sensors after drywall, the sensors in the basement, all of the panel components, connect all the wiring, program the thing (since I didn’t label all my lines this will involve figuring out what everything is), and finally add the smart integration, which will be a whole other bit of programming.

I mentioned in the last post that Dean and I ran some conduit for networking. I had decided early on that even though I’m a computer guy, we use tech everywhere, and I genuinely prefer a wired connection, there wasn’t much point in running a whole patch panel home run network install. It uses a ton of wiring, it takes up more space in the basement somewhere, and everything has to go down to the basement just to come back to where it’s going.

Instead, I wanted point to point conduit. Essentially, this means that if I need to I can connect any two rooms in the house with a cable, presumably ethernet, but anything else that the future brings that isn’t wireless like coax, fiber or even HDMI. Because this wasn’t a conventional networking setup, I didn’t have the electrician do this. With the suddenly spray foam situation we had last Thursday evening, this plan was paired down to a minimum, but since we learned they were only going to spray the first floor on that Friday, it meant that I had the rest of the weekend to put in more conduit.

I picked up ten sticks of 3/4″ EMT because there was a bulk discount, assuming I wouldn’t need all of it, but I managed to go through it, in addition to the handful that were already lying about. It’s big enough that I can run several cables in the same tube. Dean and I had run conduit in the living room to connect a TV to the basement as well as support a hidden wire wall mount. We also ran a second line from the basement to the office area in the back of the first floor and then all the way up to the attic behind the knee wall.

I ran a line from Derek’s bedroom up and over the attic bedroom and down to a junction box in the crawl space behind the knee wall on the other side of the house. From that junction it drops to a connection in Emily’s room as well as a box in that guest room.

On the other end of the house, we added a drop in our bedroom that goes up to a box in the back attic bedroom above, then jogs over to a second box in that room on the other side. I decided this made more sense than putting a junction in the knee wall crawl space, because it’s much harder to access in this part of the house. This same box also connects to the line that Dean and I ran up from the office. I started running a second line down to the other side of our bedroom, in the event we (or more likely future owners) have a non-wireless TV on the wall opposite the bed.

The spray foam installation wrapped up late Tuesday, and after I picked up some more EMT, I got the junctions on either end of the house connected together and connected the last few parts of this system. For all I know, I’ll never use this, but it’s good to have it in the event I need it. The electricians got a couple remaining items checked off the list, and the plumbers finished up the rough-in for the tubs in our bathroom and the main second floor bathroom.