Not a fan of the attic fan

When we bought our current house in December 2010, we immediately replaced the roof. We hired Tom Buzzard's roofing company, and they did a great job. After they were finished, however, they informed me that the slope on my roof was not steep enough for ridge vents to be effective, so they had installed an attic vent fan with a thermostat. But, since roofers don't do electricity, it was not wired up. They recommended hiring an electrician to do it, but I wouldn't be much of a DIYer if I didn't at least give it a shot. Early one morning last week, with a goal of beating the heat, I decided to head up and see what I could do.


Our attic entrance is a 12" x 12" opening in the ceiling of our bedroom's closet. I understand this type of entry is called an attic hatch or scuttle hole, sometimes shortened to "skutl" in real estate listings. Beware! this type of entry severely limits access to the attic. I am a relatively small guy in pretty good shape, and it was very difficult for me to get into and out of the attic. If I were an electrician, I would definitely charge extra if I had to use a scuttle hole to get into an attic. Luckily, I didn't have to find out what they charge.

The first step was clearing my wife's clothing from half the closet. She was not thrilled that I was going to be climbing up through her closet, but she was game, as long as none of her clothing got damaged. It was not a big deal to get it all out and onto the bed and floor of the bedroom.

Next, I got my ladder in place and assembled my tools. I didn't know what I was going to find up there, but I knew I wasn't going to want to go up and down too many times, so I tried to bring everything I thought I might need. As you can see at right, that included a pair of wire snips, a tape measure, a flashlight, needlenose pliers, a length of wire I had laying around, a current tester, electrical tape, and a bag of twist-on connectors.

As soon as I popped my head into the attic, I could see that the process was going to be technically easier, but far less comfortable, than I had planned. I could see that the fan included a box that was the thermostat, and that the box had two wires dangling from it. I could also see the wire that served the light in the bedroom closet right in front of my face. 

So I would just have to cut the existing wire, splice in my new wire to one end of the cut wire, attach the other end of the old wire (so it's  three-way connection), and then run the new wire over to the fan box and attach it. First, though, I had my wife cut off the power by throwing the main breaker. I decided to keep it simple.

My splice is at right. You can also see all the debris and nasty old insulation in my attic. It was dirty, hot, and the ceiling was very low. I did all the work on my stomach, balanced on a 2' x 4'. Not comfortable at all.

The splice into the thermostat box is visible above at left and right. Real simple, just twisted the black wire to the black, the white to the white, capped them, and screwed the ground into the back of the box. 

Then it was a matter of replacing the cover, setting the thermostat (I put it at 100 degrees F), and having my wife turn the power back on. The fan came on, and I knew it was a success. All in all, not a difficult project, but the logistics made it relatively uncomfortable. Still, it was more comfortable than paying $200+ for someone else to do the work.

*Important note: I didn't have a junction box on hand, so I thoroughly taped the 3-way splice before heading out of the attic. All connections need to be inside of a junction box to be safe. I have since acquired and installed the junction box, so I should be good to go.