Archive for March, 2013

Tei Explains It: Rater Role & Responsibility

Wednesday, March 27th, 2013

Question: What are my roles and responsibilities as a rater?

You are a rater.  It doesn’t matter what classification. You are considered a third party verifier of energy efficiency of real property.  Decisions made about this property regarding energy efficiency are basically “in your hands”.  Your input to the client, whether it be a builder or homeowner, is important for solid, sound decisions about spending money wisely on replacement or upgrading systems and materials.  Your opinions should be based on solid principles as well as keeping in mind the “law of diminishing returns.”

As a rater, your only responsibility is to your client.  Remember that as a rater you are the person who is certified.  You are the person who passed all of the exams and jumped through all of the hoops.  When you perform a rating, you are putting your reputation on the line as well as the whole energy efficiency industry.  When you perform a rating you are NOT really representing the company you are paid by because companies are not certified.  At this point you are a third party verifier and the client is your only concern.  If you allow any person or circumstance to change your professional judgment you are not being a third party verifier.  You are being a paid “yes” man/woman.  This can cause problems in the future if there is a complaint because defending yourself in a “compromising” situation can be detrimental to you not your employer or client.  You are actually putting your certification in jeopardy, not to mention eroding the integrity of the rating system.

Please make sure you explain to your employer that you represent the rating industry as a third party verifier when you perform a rating, and your job is to verify the features of the home as well as assist with sound, solid advice when asked to do so.  Selling or advising a client to purchase a material or service from your company is fine as long as you can justify its cost through its savings.  If asked to compromise your advice based on what the company sells is a red flag warning. Remember your certification is yours, and will be taken from you, not the company you are employed through.  Trying to “please” your builder because your employer “expects” it also becomes another red flag warning.  Again, remember whose certification is on the line.

So, the next time you hit the road to perform a rating, remember that you are representing yourself as a third party verifier as well as an entire energy efficiency community.  Please take pride in what you do and all of those you represent.

In The Field With Neil: Digital Meter Calibration

Wednesday, March 27th, 2013

Spring is in the air – so what does that have to do with your manometer calibration?  Probably nothing, except Spring means new beginnings and we need to make sure that our equipment is up to the task ahead.

Question: Why do I need to have my manometer calibrated?

Simply answer – RESNET Standard dictates it and I quote from the standard:

802.9 Equipment Accuracy and Requirements
Blower door fans used for building air leakage testing shall measure airflow (after making any necessary air density corrections) with an accuracy of +/- 5%. Pressure gauges shall measure pressure differences with a resolution of 0.1 Pa and have an accuracy of +/- 1% of reading or 0.5Pa, whichever is greater.

Blower door and associated pressure testing instruments shall be tested annually for calibration by the HERS Rating Provider or Certified Rater. The provider shall use a standard for field testing of calibration provided by the equipment manufacturer. Magnehelic Gauges cannot be field tested and shall be recalibrated by the Blower Door manufacturer annually. Field check the fan and flow measuring systems for defects and maintain them according to manufacturers recommendations. The HERS Rating Provider or Certified Rater shall maintain a written log of the annual calibration check to verify all equipment accuracy for a period of three (3) years. These records shall be made available within 3 business days to the RESNET Quality Assurance Administrator upon request.

Therefore you have 3 options for compliance…

  1. Send your meter(s) to the manufacturer for calibration on a yearly basis.  This is the most expensive method, but has the advantage of having your meter calibrated and brought into factory specifications. (Click on the manufacturer link to go to their site).
    • The Energy Conservatory – TEC recommends that all of it’s digital pressure gauges be recalibrated once per year in order to maintain the instrument’s accuracy specifications of 1% of reading (or 0.15 Pa, whichever is greater). Calibration is performed at our facility in Minneapolis, MN. The cost to calibrate a digital pressure gauge is $75. This price includes return ground shipping within the continental 48 states and Canada (expedited or air shipments will cost more). Turn around time at our facility for calibration is typically 2-3 days following receipt of the instrument (assuming no repairs are necessary). We will provide a NIST traceable calibration certificate which includes “as found” as well as “current condition” pressure data.
    • Retrotec - Our recommendation for manufacturer calibration is: – Every two years for DM-2 pressure gauges – Every five years for the entire flow measurement system.  You will need to send in or call to get a price quote.

     

  2. Send or bring in your meter to us at FSEC.  We will do a field calibration check on your meter(s).  We do not modify, adjust or certify the meter – only verify whether it is within factory specifications.  If your meter is not in spec, we will let you know and it needs to be sent out for repair/factory calibration.  Our cost – FREE to our raters.
    • Make an appointment with Jimmy Williams (jwilliams@fsec.ucf.edu) if you are bringing them by (it takes about 30 minutes to do the check)
    • Send them in to:
      Jimmy Williams, Florida Solar Energy Center, 1679 Clearlake Rd, Cocoa, FL  32922
      • You prepay for the shipping both directions.
      • We are not responsible for any loss or damage done through shipping.

     

  3. Perform a field calibration per the manufacturer as done by a certified RESNET Rater (Class 1 rater in Florida).

     

Now, one more thing – if FSEC is your rating provider, we need a copy of the field calibration for each meter you use.

Send us a copy (pdf format to: Jimmy Williams (jwilliams@fsec.ucf.edu) or by mail  to Jimmy Williams, Florida Solar Energy Center, 1679 Clearlake Rd, Cocoa, FL  32922).  The nice thing about option #2 is that not only is the calibration check free – but all the paperwork we need is done.

Tei Explains It: Rater Class Distinction in Florida

Friday, March 1st, 2013

Question: Is there a rater class distinction in Florida?

The answer is YES! Only in Florida are there 3 distinct classifications of energy raters – Class 3, Class 2 and Class 1.

Let’s review these three classification as well as requirements for each.

Class 3

raterTraining

Class 3 ratings are ratings based on construction documents. A Class 3 Rater is only recognized in Florida and can only rate buildings from these construction documents alone. A Class 3 Rater is not recognized nationally by RESNET and can only perform ratings in the State of Florida.

A Class 3 Rater must obtain 12 CEU’s (Continuing Education Units) every three years. Currently these CEU’s do not have to be registered with the Florida Department of Business & Professional Regulation (DBPR) and allow the rater to get short trainings from suppliers of construction materials and processes as long as the courses are related to “green building”, construction materials, HVAC equipment, insulation, ventilation, IAQ and energy efficiency.

Class 2

Class 2 ratings are based on a site audit. A Class 2 Rater measures the windows, walls, floors, ceiling and doors. The equipment and systems in the home are documented by make and model number and all are documented by photographs which become essential if there is a problem. A Class 2 Rater, like the Class 3 Rater, is not recognized nationally by RESNET and can only perform ratings in the State of Florida.

A Class 2 Rater must obtain 12 CEU’s every three years similar to the Class 3 Rater. Currently these CEU’s do not have to be registered with DBPR and allow the rater to get short trainings from suppliers of construction materials and processes as long as the courses are related to “green building”, construction materials, HVAC equipment, insulation, ventilation, IAQ and energy efficiency.

Class 1

raterTraining1

Class 1 ratings are based on the site audit and include a building airtightness test as well as a duct leakage total test and duct leakage to outside test. A Class 1 Rater is the only one recognized nationally by RESNET and are allowed to perform ratings in every state except for California.

A Class 1 Rater can register the coveted tax credits for qualifying homes and are also eligible to register and certify homes for EPA’s Energy Star Version 3.0 (with special training) and DOE’s Challenge Home.

A Class 1 Rater is required to obtain 18 PDU’s (Professional Development Units) in three (3) years. These PDU’s can be obtained in three different ways.

  1. Attend a RESNET Conference and obtain 18 PDU’s by documentation of sessions to equal 18 hours. You can also attend the EEBA and ACI Conferences making sure that the tracks you attend are approved by RESNET
  2. Re-take the RESNET Core Exam and pass with at least 80%
  3. Take RESNET approved classes to obtain PDU’s

It is required that all raters regardless of classification will take a recertification test every three (3) years to retain their certification. At that time they will take a Recertification class and exams relevant to their classification. A Class 1 Rater will also show proficiency by performing a blower door and duct leakage test total and duct leakage test outside.

Questions regarding rater class distinction, contact Tei Kucharski.

In The Field With Neil: Depressurize or Pressurize Airtightness Test

Friday, March 1st, 2013

Question: Should the blower door test be performed in a pressurized or depressurized mode?

blowerDoortest

The blower door test follows ASTM standard E779 (Standard Test Method for Determining Air Leakage Rate by Fan Pressurization), which states that this test method consists of mechanical pressurization or de-pressurization of a building and measurements of the resulting airflow rates at given indoor-outdoor static pressure differences.  From the relationship between the airflow rates and pressure differences, the air leakage characteristics of a building envelope are determined.  It is intended to quantify the air tightness of a building envelope and does not measure air change rate or air leakage.

So the answer is… either method is acceptable.

In general, we tend to depressurize buildings as it prevents a jet of air from being blown into the house during the test process.  However, under certain conditions it is necessary to conduct a blower door test by pressurizing the building.  For example, pressurization testing may be used to avoid the possibility of pulling known pollutants into the building during the test procedure (e.g. mold from wall cavities or crawlspaces). The pressurization test also requires an additional outside reference hose connected to the meter.

Remember it is fan sensor with reference to fan sensor location.  Therefore if we are using a DG-700 meter, the fan sensor would be installed on the B-side input tap and the outside reference connected to the B-side reference tap.

Tip from Neil:
When reporting your results – we assume that a depressurization
test was done.  If you tested otherwise, be sure to document it.

In comparing the results of a pressurization test to that of a depressurization test, in general the depressurization test will yield a slightly tighter structure.  The reason is quite simple.  A depressurization test tends to pull dampers closed (i.e. bath fans, kitchen fans and dryer vents), whereas the pressurization test will tend to force them open.