A home energy audit: turn high bills into a ranked action plan

Gather evidence before booking an assessment

Collect twelve months of electric and fuel bills, current equipment ages, thermostat schedules and the rooms that feel uncomfortable. Note recent changes such as an EV, more occupants or working from home. Record whether the bill increase comes from higher rates, greater energy use or both.

Total bill divided by kWh is a convenient household average, but it includes fixed charges that many upgrades will not eliminate. For a savings estimate, identify the variable portion avoided when consumption falls. Time-of-use plans need a further check because a kWh saved at night may have a different value from one saved during a peak period.

Ask for a prioritized scope

An assessment may include an envelope inspection, leakage testing, equipment review and measurement of specific loads. Ask which services are included and what written report you will receive. An independent assessment and a contractor’s sales visit can have different purposes; find out whether the provider also sells the proposed work.

Request estimated savings ranges, installed-cost assumptions and dependencies between projects. Separate repairs needed for moisture, electrical or combustion concerns from elective efficiency upgrades. Comfort, resilience and equipment replacement can be legitimate goals, but they should not be disguised as electricity savings.

Avoid adding overlapping savings

Suppose annual heating and cooling spending is $1,500. A weatherization project modeled to save 20% reduces it by $300 to $1,200. If a later equipment upgrade then saves 30% of the remaining spending, it saves $360, not $450. The combined saving is $660, not $750.

A thermostat change may overlap again. Solar offsets the electricity remaining after efficiency improvements; it should not be sized as if all original loads remain unchanged. The calculator page preserves separate scenario estimates, but its headline sum is not an engineered whole-home forecast. Build an order of work and rerun the inputs after each major change.

Create a decision sheet you can actually use

For each candidate project, record the problem, baseline consumption, expected reduction, installed cost, maintenance, useful life and next action. Add a low-savings case as well as the central estimate. A $500 project saving $100 a year and a $10,000 project saving $600 a year solve different budget problems.

Start with a few specific actions: correct a control schedule, replace high-use inefficient lamps, obtain a weatherization scope or request a load calculation before HVAC replacement. After the work, compare measured energy over appropriate periods and explain changes in weather or occupancy. Keep the record so future upgrades use a better baseline rather than restarting with generic assumptions.

Before you request a quote or buy

• Twelve months of electricity and fuel consumption
• Fixed versus variable utility charges identified
• Written findings and project dependencies
• Low and central savings cases for each quote
• A practical measurement plan after installation

Frequently asked questions