1-Wire Energy Management Projects

Home Telemetry and Control Systems to Monitor and Reduce Energy Costs

 My Attic Insulation Project

My house was built in 1996 so you would think it's well insulated. Well, think again. It took me 13 years to realize we had a problem with the attic insulation.

But I finally added an additional 12 inches of insulation to my attic in July 2010. So now after 8 months, here's the verdict:

  • Saved about $100/mon on energy costs over the last 12 months (electrical and natural gas) See chart below.
  • Note: My house has natural gas heating and water heating. Oven is electric and so is the stovetop and dryer.

Luckily, my wife has tracked all our major bills for years so it was very easy to create this chart. While the actual average temperature is not known (historically), I am tracking it now. Summers are about the same in Texas, really hot! Winters can be more mild or extreme year to year.

Over six years ago I started to create "catwalks" in my attic. Basically, it's a walkway to get from the back of my house (in the attic, from the garage) to the front safely. The access from the garage is the last to be finished (which is shown below).

You can clearly see the steps up from my garage level (which is not insulated). Plus, you can see the 2x4's standing straight up from the floor level. That is all "hand-railing" so nobody falls into the insulation.

On the immediate left is old inter-connect for my original sprinkler system. I simply connected to that with new wires and ran it to the new control box (off to the immediate right of this picture above).

Please notice the insulation gauges in "red/white", middle of the picture and immediately to the right. The middle gauge is reporting "R44" or about 1 1/2 inches below the highest "red" level which is R49.  (Current recommendation in Texas is R49, top if the "red" marking) The second gauge on the right is lower and I plan on addressing that in the Winter  with barrier boards (starting from the garage level) rising to the correct level for R48 of the house level.

The primary reason for creating these "cat-walks" in the past was to give me easy access to all parts of the house (rooms) for running phone, Ethernet, cable and whatever else down the walls. My house was built and finished in September 1996. Running all these lines  starting in 2000 for whatever reason seemed to be important to me. In my wildest dreams I never thought it would lead to something more important! (see diagrams at the bottom of this page).

This catwalk leads to the house front. Notice the insulation on the right and left. Yes, that's insulation, a measured R46 to R48. That's all new. I just blew in that during July 2010. More on that below.

My house has two HVAC systems. One for the day rooms and one for the night rooms. On the left of the picture above is the "day" room HVAC system. The "u" shaped pipe in the picture is the gas line for the heater part of the system.

Note: I designed the catwalk around my HVAC system to support the base width of a 12-ft ladder (a little less than 24 inches). Why? Because I have all kinds of  wiring running way up high in my attic. It's lots of stuff including controlling the attic fans. So I need a way to reach up there with my new "catwalk" system if I should ever have to do any repairs.

Updated 12.26.11

My 2300CFM attic fan crapped out this summer (2011) after about 4 years. I'm using a replacement motor from Granger's. Good thing I designed in the space in my cat-walk to handle 12-foot ladder!

The picture above shows the "cat-walk" going to my home automation system control box. The silver box on the left is part of the "night" room HVAC system. Also notice the 2x4" hand railing. Very important to provide at least one hand-railing side when building cat-walks in your attic. If you stumble and land outside the catwalk, depending on your house, it could kill you!.

The diagram above is an example of my attic before and after insulation was added. 

Wire Length

The other advantage of these 1-Wire devices is the distance you can run the wires (phone cord) from the controller.

Sources on the internet claim 1-Wire devices support distances of thousands of feet. I've not tested that but so far my shorter distance tests have been successful.

In my project I plan on running about a dozen temperature sensors with wire lengths of about 300 total feet. (This is not as easy as it sounds but we'll discuss that in my "Timeline" articles)