Ensure your builder meets, or exceeds local requirements of the Model Energy Code (MEC) recently re-issued as the "International Energy Conservation Code" which considers basic building "shell" and mechanical systems.

Insist upon air-sealed construction and have a "blower door" test done to confirm quality.

Require installation of an appropriate controlled mechanical ventilation system (cold, or very-hot climates this should be a heat-recovery ventilator type).

Choose energy-efficient windows (see Windows Tips) that are rated by the "NFRC" or have and equivalent energy performance warrantee from the manufacturer or builder.

Plan for effective natural lighting in the home's layout of floor spaces and windows and solar tube skylights where spaces would have no windows.

Install exterior insulated doors R-5, and use a minimum double-pane glass in your exterior doors with panes.

Design for "passive solar" where the homes architectural features help seasonally heat and cool the interior.

Specify your builder to use locally produced building products and other "green" building materials with greater recycled content.

Select mechanical systems and appliances that have DOE "energy guide" labels in the most efficient 20% range of their product performance category. Energy Guide labels are provided under Federal law for most major appliances and home systems.