SAN ANTONIO (San Antonio Express-News) – Along with the new year came regulations requiring new homes in San Antonio to be 15 percent more energy efficient.

 A part of the city’s Mission Verde initiative, the regulations will make tighter home design, better insulation and low-flow toilets standard market features.

 Builders estimate that it will cost 1 to 2 percent more to meet the requirements, adding $1,000 to $2,000 to every $100,000 a home costs.

 The biggest changes under Mission Verde are the requirement of a blower door test, which measures how tightly a building is constructed, and air-conditioning ductwork testing.

 Builders who use spray foam insulation will exceed the requirements of Mission Verde, and those homes will not be required to have ductwork testing.

 Other changes include insulating water pipes and removing water waste from irrigation systems and inside the home. Toilets will not be able to use more than 1.28 gallons per flush on average. Shower heads should have a maximum flow of two gallons per minute, and bathroom faucets should have no more than a 1.5-gallon-per-minute flow.

Compliance with these regulations will be checked during the permitting process and when inspectors visit the job site.