Home Energy Rating System (HERS)
There are various types of HERS verifications and ratings; Some to verify
quality installation of new or replacement systems and some to provide analysis
of existing buildings, aka HERS II. We have equipment to provide diagnostic
analysis to establish quantifiable measurements of energy elements. The 2013 energy code now includes some mandatory HERS verifications for all projects as well as HERS measures used in Title 24 energy models to gain compliance. HERS II analysis is
used to evaluate existing buildings and help develop cost effective measures to
improve the home’s performance.ABP is also proud to offer Energy Star Homes verifications.
Verification of Title 24 Measures:
Maximum Duct Leakage (mandatory max 6%)
Ducts in Conditioned Space
Quality Installation of insulation (QII)
Blower Door infiltration tests
Duct Leakage to
Ventilation air flow (mandatory ASHRAE 62.2 levels)
Verify existing conditions
It used to be that HERS testing was only required when
credit was taken for a particular measure on the Title 24 report but now there
are mandatory HERS Tests that must be done for all new homes and some addition
All new homes with ducted systems must be verified to have
a maximum leakage of 6%. Also it is required that the systems be sized using ACCA manual D, J and S methods. These reports need to be provided to the HERS Rater.
New duct systems in any climate zone must be verified to have
a maximum leakage of 6%. That used to be the level that would get credit. So
now if one wants to take credit for a low leakage duct system it would be for a
number even lower which is possible with good techniques.
Ventilation is now mandatory as per ASHRAE 62.2 and the
levels must be verified by measuring air flow. This is to be done for range
hoods and full bathroom exhaust fans as well as the system providing
ventilation for the whole house. Applies to all new homes and where the
addition is greater than 100 square feet
Whole house ventilation sized for the conditioned floor area
and occupancy of the home
Range Hood minimum 100 cfm and bathroom fan minimum 50 cfm.
All replacement furnaces, air-conditioning components, and duct systems trigger verifications. The installing
contractor needs to register with CalCERTS and
complete a CF-1R and CF-2R for the project.
As a third party HERS rater I am not allowed to perform any repairs but I will
do what I can to help pinpoint leakages. If we are just analyzing ducts to
improve performance I can do some repairs.
Quality Installation of Insulation (QII)
It is also quite common that insulation is installed poorly at best. Infrared
imaging has demonstrated just how catastrophic even a seemingly small corner of
missing insulation can be. This is also one of the best opportunities to make a
truly high performance home, and it will never be easier than the first time
insulation is installed. QII can be a very tough measure with comply to and the framing
and insulation contractors must be aware if it is required. The
QII protocols for 2013 all but eliminate standard batt insulation as an option.
So the alternates are blown in cellulose or fiberglass or foam. QII also starts
with the framing so it cannot be left to the insulation contractor only. To get
an idea you can see the checklists here that the installer must fill out on line and which is the same that the HERS rater uses to verify this extensive measure. A pre-construction meeting is recommended to
know what is expected.
There will typically need to be a number of verification visits for QII. The HERS rater must see it to verify, no "I promise I did it" kind of thing.
HERS II This is the whole house evaluation of the various systems that comprise the energy use of the home. This analysis can include a blower door test, duct test, accounting of major appliances, combustion safety analysis and more. As a HERS II rater I can also verify existing conditions as may be called for in certain types of Title 24 analysis.