A sample audit scenario

If a home is at least 20 years old, an audit might return these results: 

  • Minor air leaks both within the home and along the home’s exterior
  • Mechanical issues, such as old and leaky ducts; inefficient, old appliances and HVAC system 
  • Old windows, a source of drafts
  • Insufficient insulation  
  • Uninsulated ducts in unfinished spaces, which would benefit from insulation

Is budget a priority?

If you’re funding repairs on a small budget, your best bets include tightening up air leaks, tackling home mechanical issues, and using storm windows. Tightening up your home can save $150 per year on energy costs, according to the California Energy Commission, but costs less than $75 (for mastic paste or foil tape to seal ducts; indoor and outdoor caulk; and weather stripping for doors).

Tackling mechanical issues — adjusting appliance settings, putting a timer on a water heater, adding programmable thermostats — can reduce bills by up to 50%, according to the Alliance to Save Energy. 

Using storm windows ($30 and up) or plastic film-based kits ($25 for one large or two small windows) until you can replace windows can save 25% to 50% of heat loss during winter, lowering bills, ASE says.

Save the tasks that require a contractor and expensive materials, such as insulating ducts in unfinished areas, adding insulation generally, and replacing windows, for your flusher future.

If you’re payoff minded

Willing to shell out for all the repairs on your list, but want to start with the work that pays off fastest?

First replace old windows, then old appliances. 

The logic: Windows make up a large portion of your home’s exterior surface area, so improving their insulating power can lower energy costs by 30%, according to the ASE. Replacing windows can be costly — more than $10,000 for vinyl or wood windows, according to Remodeling magazine—but it’s one of the best home projects in terms of payoff. You can recoup about 71% of the cost in added home value at resale, according to the magazine’s annual Cost vs. Value Report.

Upgrading your appliances throughout the home can reduce energy consumption by 20%, and you’ll see results in your bills immediately, ASE reports. Energy Star provides guidance on what to look for in different appliances. Replace the oldest first. Chances are, the older the appliance, the more inefficient it is. 

Consider major insulation upgrades for your next priority since they also may be eligible for tax credits through 2011. Tightening up your home, sealing ducts, and other small steps will also help with energy bills. 

When there’s an urgent need

Got less than a week to make some changes? DIY fixes are fastest. With a trip to the hardware store and a few hours of free time at night or on the weekends, you can seal minor air leaks around the house. If you’re capable of adding insulation, that, too, can take less than a week, allowing for purchase and installation. 

Two to four weeks is sufficient to hire a pro to measure, quote, and install insulation around ducts or elsewhere in the home. 

In two to three months you can replace windows. The process requires a rep to measure your windows and provide an estimate; up to six weeks or more for the order, depending on manufacturer and any custom work; and installation, which is usually done in about a day. If schedule is a major issue, ask the window rep up front about the fastest-available models. 

In general when hiring contractors, keep in mind their availability will be affected by the time of year. For instance, it’s better to replace a furnace in summer than January when they’re busy with repair calls. 

Assess your capability; the job’s level of effort

How comfortable are you on a ladder, working with fiberglass bats, or installing a $500 picture window on the front of your home? Assess when outsourcing makes more sense because your mistakes might prove expensive, you have limited time, or you lack confidence in your DIY skills.

Many energy-efficiency upgrades, such as sealing small air leaks, putting in storm windows or plastic window liners, and installing some consumer appliances, are easy. But you’ll need pros for window installation, insulating ducts in unfinished spaces, and, possibly, adding insulation elsewhere in the home.

No matter your budget, DIY abilities, timeframe, or ambition, any steps you take will show results on energy bills in a matter of months.