As I mentioned after my final class recap, I was considering two final articles; the first one was a recap of the training process, followed up by a comparison of the systems. Many people tend to believe that there is no difference between the systems, except for the CAZ testing required by BPI. I can honestly say that comparison is really a disservice to both organizations. For purposes of this article, I am basing the BPI standards on the combined Building Analyst (Feb 2005) & Building Envelope Standards (Aug. 2010) and the RESNET standards on a HERS Rating.
Modeling / Rating:
In a recent discussion on one of the Linked In boards, L. Terry Clausen P.E. who also happens to be a certified BPI Instructor made the following observation “BPI does not model (i.e. computer simulation) or rate (score) houses because that is not their purpose.” I could not have stated it any better, but therein lays one of the biggest fundamental differences between the programs.
|RESNET – fully recognized program used by USGBC LEED®, EarthCraft®, ENERGY STAR®, the mortgage industry (MLS Listings, EEM’s), etc…||NONE|
Disclosure / Conflict of Interest:
|Mandatory with a specified form||At this moment – not required per the standards… soon changing?|
Ahhh, one of the biggest misconceptions out there; BPI is only for older homes & RESNET is only for new homes. Based on some of the items marked (*), one might easily be led to that conclusion especially if you combine that with quotes like this;
The purpose of a BPI audit is to establish a procedure for evaluating the improvements to a home that will improve health & safety, increase the durability of the structure and increase the energy efficiency for the occupants, and in a cost effective manner. The result of a BPI audit is a comprehensive list of prioritized recommendations to this purpose. The BPI audit does not require computer modeling but many BPI auditors do include computer modeling as part of their service. The BPI audit provides valuable guidance to homeowners who need to differentiate fact from fiction in the world of marketing.
I love elevator sales pitches; unfortunately, I am not buying it and happen to know better. First, it is impossible to know what is cost effective & what is truly valuable without modeling the baseline & proposed changes. BPI has also recognized this and is requiring it in its new standards, which they still have not approved. The funny part about the new standards, they do not reference any of the typical “auditing” items listed below, or they may be taking a page from RESNET, where that is included in specified software. Just as a quick side point, you can make a building more Energy Efficient but it is up to the occupants for how it is utilized. (Energy Efficiency Vs Conservation Article)
|Outside Evaluation||Numerous requirements to properly model & rate the house (Model #’s on Air Handlers to pull efficiency #’s) window size, footings, walls, rim joist area, etc… are all looked at & evaluated||Required for a Heat Loss & Savings Calc. to be within 10% of actual **|
|Building Orientation||Required to actually measure & rate building||Not mentioned or required|
|Type & color of materials||Required to actually measure & rate building||Not mentioned or required|
|Shading of Exterior Windows||Required to actually measure & rate building||Not mentioned or required|
|CO Outdoors||Not required to be done*||Required to get baseline number and zero it out for indoor monitoring|
|Check Gas Line & Meter for leaks||Not required to be done*||Required to be checked, including gas lines in the house|
|Attic||Required to measure & rate installation & note problem areas||Required for a Heat Loss & Savings Calc. to be within 10% of actual **|
|Wall Insulation||Required to measure & rate installation & note problem areas — for new housing following certain programs, the installation is to be verified by a rater before drywall is installed||Required for a Heat Loss & Savings Calc. to be within 10% of actual **|
|Crawl Space, Basement, Rim Joists||Required to measure & rate installation & note problem areas||Required for a Heat Loss & Savings Calc. to be within 10% of actual **|
|Windows||Required to measure & rate installation & note problem areas||Required for a Heat Loss & Savings Calc. to be within 10% of actual **|
|Lights & Appliances||Types of appliances needed, and % of CFL’s to incandescent bulbs needed to perform calculations||Nothing listed in the Standards for audits|
|Blower Door Tests||Required & similar||Required & similar|
|Ventilation Standard Measurement||Utilizes ASHRAE 62.07 &/or 62.89 depending on your local codes||ASHRAE 62.89 currently —new standard is still awaiting approval & it will only use 62.07|
|Duct Leakage||Required use of blower door & duct blaster testing for accurate numbers||Not required under the Building Analyst portion – mentioned in Envelope section, but they allow the use of pressure pans and guesstimating|
CAZ (Combustion Area Zone) Testing:
First, I will be one of the first to say that Combustion Safety and maintenance of these items is of paramount importance in a home. With that said, both organizations get a FAIL on this subject.
RESNET currently does not require CAZ, which I actually agree with – “because it is not their purpose”. They however have decided to try to be all things to everyone & adopted a standard that seemingly takes the worst portions of the old BPI standards they could find and making it worse. As an FYI, while RESNET has adopted a standard, it does not mean it is actually fully in place. They first need to add in another 32-hour class and train the trainers, before it will be fully implemented
BPI with their Health & Safety First approach has unfortunately created a nightmare where they have individuals drilling into ductwork that they should not be & evaluating systems that they are not qualified to touch. Fortunately, in their new standard, they are eliminating the draft testing and thus eliminating quite a few issues I have with there system. I would also wager that in quite a few locales, even most of the testing that is remaining is not allowed unless a licensed HVAC technician does it.
In all reality, the bulk of BPI’s testing should be done yearly when a Homeowner does their annual tune-ups & just utilize the Worst Case Pressure Test for the audit(s) – that really is the safest & healthiest option for all concerned parties. While we are on this subject, let’s talk about CO Detectors – you really should push for them to be installed in every house that has an ERV, HRV, attached garage & I would say an operable window. Whether one has gas appliances is irrelevant as CO is produced by cars, lawnmowers, grills, etc… I remember when I lived in Phoenix, reading about a family dying from CO poisoning – the reason, they brought in a charcoal grill to stay warm not realizing the issues that it would cause.
Standards of workmanship:
This section is quite simple, while RESNET truly is a modeling and rating program, BPI has numerous standards on how products are installed, minimum specifications, do’s & do not’s. The BPI program is truly not setup to perform true audits, but setup to promote certain standards or actual retrofitting guidelines which unfortunately the government is trying to get into.
There is one more major difference, that is BPI requires a Test-In Test-Out approach, while RESNET only requires one for older properties. In my opinion, and many others that is a mistake for retrofitting work & one reason why RESNET is not involved in the Home Performance with Energy Star (Retrofits, Energy Improvements, etc… on older houses).
To my knowledge, only RESNET has adopted an Infrared Standard for diagnosing houses. With that said, they really should not have even bothered. I think the two best terms for it was brought up on EnergyAuditorTalk where it was referred to as a “nightmare” and that this “belongs in a laboratory not the real world.” Quite honestly, they need to leave things like this to the experts at ASTM who understand NDT & that already have a valid process instead of appearing to be pulling a money grub. (FAQ’s on Infrared Thermography)
In closing, both organizations truly have some good programs that actually compliment each other. I would say that in a perfect world, BPI & RESNET should stop playing grab ass & do what they have been talking about for a while – RESNET Certified Raters should do the Test In & Test Out audits, while BPI Certified Contractors actually do the work.