We perform HERS Ratings in Indiana and Kentucky. HERS Ratings are conducted primarily on new construction residential properties for the purposes of energy code compliance verification, ENERGY STAR Home certification, or other program certifications. Essentially, a HERS Rating gives a score of how efficient the home will be for the home owners, and is oftentimes compared to a MPG rating for cars and trucks.
There are four basic steps to conducting a HERS Rating on a new house.
Conduct a "Projected Rating" using energy-modeling software that is based on the blueprints and details for how the home is to be built.
Perform an on-site "thermal bypass inspection" after the house is insulated, but before drywall is installed.
Once the house is complete, pressure-test the house for air-leakage, duct-leakage, and test airflow through bath fans and mechanical ventilation. Inspect attic insulation for proper depth and gather all model numbers from HVAC equipment, water heaters, refrigerators, and dishwashers.
Input all the confirmed data back into the energy-modeling software.
The Projected Rating - A certified Home Energy Rating System (HERS) Rater takes blueprints and specs for a new home and enters all the building's details into an energy modeling software program.
For a list of all the details needed to conduct a Projected Rating, download our one-page cheat-sheet here.
Thermal Bypass Inspection - The HERS Rater does an inspection of the framing, insulation, air-sealing, windows, doors, and ductwork before the drywall is installed. The insulation must be installed completely, with no gaps, voids, or compressions anywhere in the wall or floor cavities. All six sides of the insulation must be in full contact with an air-barrier. All penetrations through floors, walls, and ceilings to unconditioned space must be air-sealed properly with foam and/or caulk. Ductwork located outside of conditioned space must be air-sealed and insulated properly.
Click here for a copy of the Thermal Bypass Inspection checklist.
Final Inspection - The HERS Rater conducts a series of pressure tests using a blower-door and a duct-blaster. The air leakage in the house must be minimal - less than 40% natural air-changes per hour (ACHn) - as well as the duct leakage throughout the HVAC system - as designed in the HERS Rating report.
For energy code compliance in Indiana and Kentucky, the duct leakage to outdoors is limited to 8 CFM/100 Sq Ft of "conditioned space". In Kentucky the commonwealth also requires a DTV Form (Duct Test Verification) to be completed for each house when ductwork is located in attics, crawlspaces, or garages.
After the house has been confirmed to perform as intended, the HERS Rating file is sent to the HERS Provider who checks to ensure data accuracy. A final report is emailed to the builder of the home, who is to provide it to their client (the home owner) after the home is sold.