Normally, estimating total energy use requires performing a computer analysis of each home design. However, to simplify the process, we have developed pre-approved design packages of energy features that meet or exceed the ENERGY STAR requirements.
For each climate region, pre-approved ENERGY STAR design packages are provided. The variety of packages gives the plant fairly wide latitude in deciding how to design an ENERGY STAR certified home.
A package contains requirements for several features that must be used together to qualify as an ENERGY STAR certified manufactured home. All the packages are roughly equivalent in energy terms. That is, applied to the same home, all packages will result in approximately the same total energy use. Therefore, saving energy in one area (e.g., by using tighter ducts or installing a programmable thermostat) will result in offsets elsewhere (e.g., by allowing a higher Uo-value).
The design packages are divided into four sub-tables, one for each climate region. Each sub-table is divided into two or three sections according to expected maximum duct loss percentages (e.g., 3%, 5%, or 7%). Each of these sections is further divided into two or three parts, one for each heating system type: gas/oil, heat pump, and electric resistance, if applicable.
In cases where a state has more than one climate region, the state-by-state climate region tables provide the “primary” climate region and lists counties in the other regions as “exceptions.” Where the destination of a home is not known prior to manufacture, and the plant's typical shipping radius covers more than one region, it is advisable to select an ENERGY STAR package from the region with the more stringent thermal envelope requirements (Climate Region 1 is the most stringent, Climate Region 4 the least).
Once you have printed the tables, select the climate region where the ENERGY STAR certified home(s) will be sited. Once you have identified your correct region, select the ENERGY STAR design package for that region following the steps described below.
The column “High Efficiency WH” indicates requirements for water heater efficiency, and the column “Programmable Thermostat” indicates if a programmable thermostat is required.