Home Energy Efficiency Score Calculator

Perform a high-level thermal audit on your home. Calculate your aggregate efficiency score, find your biggest energy leak, and see which upgrade gives you the best ROI.

Audit Results

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The Physics of a House: Why Are You Paying to Heat the Neighborhood?

When utility bills skyrocket, most people assume their air conditioner is broken. The truth is usually much simpler: the house itself is broken. A home is a physical box trying to maintain an artificial climate against the hostile physics of the outside world. If that box leaks, your heating and cooling systems must run constantly just to break even. Our Home Energy Efficiency Score Calculator pinpoints exactly where your thermal envelope is failing.

The Hierarchy of Upgrades

Do not buy solar panels for an uninsulated house. It is the equivalent of pouring more water into a bucket with a hole in the bottom. You must fix the hole first. The strict engineering hierarchy for home upgrades is:

  • 1.Seal the Leaks (Insulation): Heat rises. A poorly insulated attic acts like an open chimney, sucking all the expensive hot air out of your house in the winter. Upgrading to thick spray-foam insulation has the highest Return on Investment (ROI) of any home upgrade.
  • 2.Stop Glass Transfer (Windows): Single-pane windows offer almost zero thermal resistance. You can literally feel the cold radiating through them. Upgrading to double-pane windows traps an insulating layer of gas between the glass, instantly dropping HVAC run times.
  • 3.Upgrade Generation (HVAC): Once the 'box' is sealed tightly, *then* you upgrade the machine making the heat. Moving from an old gas furnace to a hyper-efficient electric heat pump minimizes the raw energy needed to change the temperature.

The Lighting Low-Hanging Fruit

While insulation requires contractors, lighting does not. Old incandescent bulbs waste 90% of their energy generating heat rather than light. During the summer, these bulbs actively fight your air conditioning, costing you money twice. Simply swapping every bulb in the house to LED is a fast, cheap upgrade that permanently lowers your baseline load.

Putting Your Score into Action

Once you understand your building's weaknesses, you can start running the math on specific upgrades. If our calculator suggested an HVAC upgrade, jump to our Heat Pump vs Gas Furnace Calculator to see the exact running costs. If it suggested lights, check the LED Savings Calculator to find your break-even point. Once the house is sealed and efficient, you can finally size a solar array perfectly using the Solar Sizing Tool.

Explore Next: Targeted Upgrades

Frequently Asked Questions

Is it better to replace windows or add insulation?

Insulation almost always provides a faster financial return. While replacing single-pane windows with double-pane is crucial for stopping drafts, high-quality windows are incredibly expensive. Adding a thick layer of blown-in insulation to an attic is relatively cheap and yields massive, immediate drops in heating and cooling costs.

What is an R-Value?

R-Value is a measurement of thermal resistance. It dictates how well a material stops heat from passing through it. A standard uninsulated wall might have an R-Value of R-3. A wall properly packed with fiberglass or foam can hit R-15 to R-20. The higher the number, the more efficient the house.

Do smart thermostats actually save money?

Yes, but they rely on your habits. A smart thermostat (like Nest or Ecobee) saves money by detecting when you leave the house and automatically letting the temperature drift slightly, reducing HVAC run time. If you work from home 24/7, the savings are much smaller.

How do I test my house for drafts?

Professionals use a 'Blower Door Test' which depressurizes the house to find exact air leaks. For a DIY approach, light an incense stick or a candle and walk slowly around your window frames, electrical outlets on exterior walls, and door thresholds. If the smoke pulls sharply in a specific direction, you have found an air leak.