Home Efficiency

In late 2018, my husband and I bought a mid century home in the suburbs of Los Angeles. In addition to salmon pink wallpaper, baby blue carpet, and asbestos-laden popcorn ceilings, our home came with basically no energy efficiency features. With both budget and the environment in mind, I set out to transform this home into a model of how homes can be retrofitted for a sustainable future. This page documents some of the changes we implemented in our first five years of homeownership. 

The Impact So Far

When we first moved in, the house interior would easily reach 90 degrees if the A/C was not turned on and during heat waves (95 degrees or hotter), the A/C would run constantly just to maintain 80 degrees inside. Now, we do not need to run the A/C at all during typical summer days and during heat waves, the house will not exceed 83 degrees without A/C. We've also found that we can run the A/C for 2-3 hours before noon (when solar is abundant and energy is cheap) then not need to run it at all in the afternoon when demand is high to maintain a comfortable temperature. Our water usage is also consistently in the lowest 10% for our area without feeling deprived. 

The Groundwork

Fortunately, our home did include some recent upgrades. Nearly all the windows in the house had been replaced with double pane (though not all of them well sealed), the HVAC system was only two years old, and the roof was under a decade old. Awesome, as these can be some of the most expensive efficiency upgrades in a home.

Building Envelope: Insulation, Windows & Doors

Los Angeles is famous for its beautiful year round weather, but that's not quite true in the San Fernando Valley, where it frequently swings between 30 and 110 degrees Fahrenheit throughout the year. Despite that, homes built after WWII did not generally include insulation in the attic or walls or even deep roof eaves to shield the windows so these homes get hot in the summer and cold in the winter. According to the Department of Energy, over 55% of household energy use is spent on heating and cooling the home. By improving the building envelope (e.g. the physical barrier between conditioned and unconditioned space, like walls, windows, roof, etc.), the home's temperature can be better regulated without additional energy inputs. This is the most important, but often most expensive part of retrofitting a more climate-resilient home.

Our home had blow in insulation in the attic, but it was thin, dusty, and likely lacked flame retardant. We replaced this with batts of R-30 fiberglass insulation. As we have renovated each room, we have been sure to add R-13 fiberglass insulation to all exterior walls. As of July 2023, we have tackled 75% of the house's exterior walls and have noticed the house is dramatically more comfortable and with reduced temperature differences between rooms. 

Most of the windows in the house had been replaced with double pane windows. However, the two sliding glass doors to the backyard and the garden window in the kitchen were still single pane and drafty. One of the sliding glass doors and the garden window have since been replaced with double pane, low E windows and the difference is noticeable. The final sliding glass door is on our list when we redo the addition.

The front door was a west facing solid wood door that would swell in the summer and stick or shrink in the winter and turn drafty. We replaced this with an insulated Energy Star door with low-E glass that no longer sticks or lets in drafts. 

Climate Control

Building envelope improvements don't eliminate all needs for heating and cooling, so we sought ways to improve those systems directly. One of the first things we did was install a smart thermostat (we opted for the Ecobee, as it was HomeKit compatible). This installation allows us to set custom schedules, including cooling the house when solar energy is abundant, as well as to adjust the temperature when we're away.

The smart thermostat also allowed us to enroll in a pilot program with the LADWP. Under this program, LADWP can adjust the temperature settings during periods of high demand to shed load (in exchange for an annual Amazon gift card). Generally, this has meant our A/C is automatically set to 82 degrees when it is over 100 degrees outside (we generally set it at 78). In September of 2021, I noticed that the thermostat had been set lower than usual (around 72) with a note that they were pre-cooling our house in anticipation of a high demand event. This way, the house would be sufficiently cool that the A/C would not need to run at all during this high demand period. I'm pleased with this more proactive approach, which could help prevent some of the complaints from a similar program in Texas. 

Electrical, Lighting & Solar

The other 45% of home energy use is on running appliances, lighting, etc. Our very first order of business was to replace all the incandescent bulbs with LED versions. According to the Department of Energy, LEDs use at least 75% less energy than incandescents and last 25 times longer, resulting in less waste in power and the landfill. 

More intensively, we rewired the entire house and we set our sights on the panel box. 100 amps, overloaded circuits, and no grounding. Unacceptable. We upgraded to a 200 amp panel that could safely support modern appliances, solar panels, and a future EV charging station. We also replaced most of the light switches with Lutron smart switches. We can control our lights from our phone and ensure that no lights or fans are left on when we're away. My husband also wrote a script that turns on several lights for 3 minutes when we come home, so we don't have to leave a light on all night just for when we return. 

As we've replaced appliances, we have prioritized Energy Star rated versions that use less electricity. To date, we've upgraded our dishwasher and fridge.

With over 300 sunny days a year, solar in Los Angeles is a no-brainer. We installed a 10 panel array (330 W each) capable of generating 3.3 kilowatts per hour. Outside of the summer months when A/C becomes a necessity, we find that this almost completely meets our  usage (see Solar Panels). Hopefully, more insulation and energy storage in an electric vehicle will improve this further.  

Natural Gas Reduction

The typical Los Angeles single family home uses natural gas for heating and cooking as this was historically a cheap fuel and the pipelines were built in as the area was developed. However, with the war in Ukraine, we've seen natural gas prices shoot up thanks to a volatile global market. We've also learned more and more how much using this fossil fuel contributes to indoor air pollution and increases house fire risks, especially after earthquakes when pipes break and leak. 

Our house came with a tank water heater, which we replaced with a tankless version. A tankless water heater uses less natural gas and electricity as it heats water on demand, rather than trying to keep a whole tank warm constantly. We noticed a 20-30% reduction in our natural gas bill. Looking back, we wish we had opted for an electric version that uses heat pump technology and possibly solar water heating. Since tankless water heaters can last for 20-25 years, we're locked into this for awhile. 

On the plus side, we replaced our gas range with an electric version that includes an induction cooktop. While cooking is only a tiny portion of home gas usage, it is a major contributor to poor air quality since the gas flame is inside the house. Induction cooking is more efficient and much faster than traditional resistive electrical cooking as electromagnets are used to heat the pans directly. Another bonus - by heating the pans directly, less heat is released into the kitchen, keeping it nice and cool.  

Indoor Water Efficiency

Los Angeles requires that all homes sold must be fitted with low flow shower heads and toilets, so the seller replaced the 5-gallons-per-flush (gpf) toilets with more reasonable 1.28 gpf versions. The shower heads were also replaced, but cheap and flimsy, so we picked up replacements on clearance. After we moved in, we installed an aerator on the kitchen tap to slow the flow of the water without sacrificing pressure or power. 

As part of our kitchen renovation, we replaced our old dishwasher with an Energy Star rated version that reduced the water per run from 10 gallons to 4. 

We also installed a Flume water monitoring device that alerts us to leaks and helps us keep an eye on our overall usage. 

Lawn & Irrigation

The previous homeowner was a single man. So you can imagine our surprise when we received our first water bill and saw that he had been using 16 HCF (hundred cubic feet) or nearly 12,000 gallons of water every two months (more than double what we currently use as a household of three). 

How? The aforementioned high-flow toilets and faucets definitely didn't help, but ultimately, we believe it was landscaping. The gentleman had kept both front and back lawns and dozens of plants lush and green with plenty of water - with a significant leak to boot. We ripped out the front lawn and replaced it with over 500 square feet of raised beds for growing vegetables, and drought tolerant plants and succulents. To irrigate that garden, we installed a Rachio smart controller that waters only when needed and drip irrigation lines buried under several inches of mulch to minimize evaporation. Unfortunately, the heat waves have still been frying my summer plants, so I've been experimenting with shade cloth, ollas to promote deeper, less frequent watering, and prioritizing drought resistant seed varietals and native plants. 

LA City's Department of Sanitation gave away 55 gallon rain barrels so I acquired a couple. Even with only half of our roof guttered, these barrels fill up in just one day of moderate rain and meet my watering needs all winter and spring.

Behavior

As a self-proclaimed sustainability fanatic, I don't mind going a little out of my way for the more sustainable option. But I know its not realistic to ask everyone to do the same so I focus on more structural or one-off ways to make a difference. But I would be remiss not to mention the behavior changes we've implemented to run a more sustainable household.

What's Next?

Last Updated 7/8/2023