Two years ago, questioning a group of builders about the biggest problems facing the green and energy-efficient building movement would more often than not elicit a popular complaint: There’s no industry-wide standard.

While that refrain can still be heard today, it seems to be fading out as more and more builders have turned to what may be becoming the industry’s default: HERS scores.

In model homes across the country, small thermometer heat charts are popping up next to thermostats as builders use their Home Energy Rating System (HERS) score to compete with other new homes and, importantly, existing-home inventory.

Even as the number of homes being built in the U.S. has declined in recent years, the percentage of new homes being rated by HERS has been increasing, says Steve Baden, executive director at Residential Energy Services Network (RESNET), which developed the HERS rating.