what is a hers rating? | home efficiency santa fe

What is a HERS Rating?

Dee BangertPre-Construction Services

HERS Raterwww.palosantodesigns.com

In 1995, representatives of the national mortgage industry, the National Association of State Energy Officials, and Energy Rated Homes of America founded the Residential Energy Services Network (RESNET).

RESNET, guided by the mortgage industry, developed national standards for home energy ratings and energy mortgages.

In 2002, RESNET became a 501 (C) (3). RESNET develops the rating standards and

administers the training and certification of Raters and Quality Assurance Providers.

HERS = Home Energy Rating System

Before July 1, 2006 the rating was known as a “score”.

Now the HERS Index is used to compare a home’s energy use with that of the American Standard Home - sometimes also called the “Reference Home”.

The Reference Home has a set of criteria which do not change, such as:◦ It is wood frame and the same size as the rated home◦ It has 18% glazing area and distributed equally between

North, South, East and West.◦ Same fuel and equipment type as the rated home for

heating, cooling and water heating, except with efficiency ratings of federal minimums.

HERS Index

HERS IndexThe American Standard Home is given a score of 100, while a Net Zero Energy Home is Given a 0.

Each point on the Index equates to 1% energy use. A lower

number is better.

Energy Star version 2 Required a HERS Index of 85, 15% better

than the Reference House.

A HERS Index is also used by LEED for Homes and the National

Green Building Standard. Lower Index scores are required for higher levels of certification.

Plan Evaluation◦ A Projected Rating can be given from a set of plans and

specifications. Estimates are used for test data such as air infiltration (Blower Door) and duct leakage.

◦ Measurements can be taken for existing home’s window, door, floor and wall areas among other things.

On Site Inspections◦ Insulation Inspections allow for the highest grade of installation

to be used in the rating.◦ A Thermal Bypass Inspection is required by Energy Star.

Testing◦ A Confirmed Rating will require a Blower Door and Duct Leakage

tests. ◦ Palo Santo suggests having a Duct Leakage test done at rough-

in to ensure success at completion.

Components of a HERS Rating

Plan Evaluation◦ It is suggested that this be done toward the end of the design

phase, so the design can still be modified to meet the energy goals.

On Site Inspections◦ Under slab insulation inspections can be eliminated if photos

are provided, but it will still receive the lowest grade for installation. This can affect the HERS Index.

◦ A Thermal Bypass Inspection is required by the City of Santa Fe’s Residential Green Building Code, LEED for Homes, and Energy Star.

Testing◦ A Confirmed Rating will require a Blower Door and Duct

Leakage tests.

Components of a HERS Rating

Tax Incentives – New Mexico◦ Sustainable Building Tax Credit, for homes

certified in Build Green New Mexico or LEED-H could receive a tax credit.

◦ Solar Tax Credit – 10% or up to $9,000 for homeowner.

Tax Incentives – Federal◦ Energy Efficient Tax Credit - $2,000 for the

contractor (through 2016)◦ Solar Tax Credit – 30% of cost for homeowner

Why does a new home need a HERS Rating?

RESNET has approved three

different software

companies for HERS Ratings.

REM/Rate is the most used by

HERS raters in New Mexico.

HERS Rating Software

Libraries allow for many building types

to be created. Through the use of the library items, a

house can be created with any

number of combinations of wall

type, foundation type, ceiling type

and mechanical equipment.

Utility Rates are also set to report on cost

of energy used.

HERS Rating Software

Above Grade Wall Types

HERS Rating Software

Mechanical Equipment

Requires information such as:

The efficiency ratings of heating, cooling and water

heating equipment

Location of equipment

Thermostat settings

HERS Rating Software

Air Infiltration (Blower Door)

These results are estimated for a projected rating based on the

guidelines of the program qualifying for. Final results are

entered for a Confirmed Rating.

Mechanical Ventilation Systems

Heat Recovery Ventilators and Energy Recovery Ventilators

help HERS score. Other ventilation is needed to qualify

for some green building programs. City of Santa Fe now requires meeting ASHRAE 62.2.

HERS Rating Software

Duct Systems

Allows for more than one system.

Requires information such as:

Location, R-value of insulation on ducts as well

as which mechanical equipment uses it.

Leakage rates are estimated for the Projected Rating based on the program,

and final results are entered for the Confirmed

Rating.

HERS Rating Software

Blower Door: Tectite

Testing Software

Quick Reports:Energy

Annual load Annual Consumption

Annual Energy Cost

Quick and easy way to see how changes effect energy usage

REM/Rate Reports

Quick Reports:Compliance

HERS IndexPass/Fail for Energy Star

Pass/Fail for Federal Tax CreditPass/Fail for IECC and other

energy codes

Quick and easy way to see how changes

effect the HERS Index

REM/Rate Reports

Projected Rating:Energy Star

This is what you would receive as confirmation

that the planned building meets Energy Star. Once

the final tests are completed, the file is

reviewed by the Quality Assurance Provider and

the word DRAFT is removed.

This is just one of many reports available.

REM/Rate Reports

Detailed ReportsAction Report

Action - Graphic ReportAir Leakage Report

Building fileBuilder Affidavit

Building File ReportComponent Consumption Summary

Component Consumption Summary GraphicComponent Loads Summary

Component Loads Summary GraphicComponent Design Loads Summary

Component Design Loads Summary GraphicEconomic Summary

Emissions ReportEnergy Cost & Feature

Equipment SizingFuel Summary

Lights and Appliances SummaryPerformance Summary

Performance Summary GraphicPerformance Factors

Source Energy & EmissionsUtility Bill Reconciliation 

ASHRAE 90.2 ReportsEnergy Star Reports (7)

IECC Compliance Reports (1998 – 2006)

REM/Rate Reports

Palo Santo Designs LLC is an Award Winning General Contractor specializing in the design and construction of Fine Custom Homes, Renovations and Distinctive Commercial Spaces in the Santa Fe area. Our experience is unsurpassed in the design and construction of high performance buildings, utilizing the most effective methods for energy and water efficiency, sustainability and comfort.

Choose Palo Santo Designs for your Custom Home Project in Santa Fe