Technical Bulletins
Tips and guides for getting the most out of the Duke Energy RNC Program
Spray Polyurethane Foam Benefits
Utilizing Spray Polyurethane Foam (SPF) is an effective option for reducing energy costs and lowering utility bills by creating a tight seal that prevents air movement. According to studies by the U.S. Department of Energy (DOE), up to 40% of a home’s energy loss is due to air infiltration, often through wall outlets, windows, doors and top/bottom plates.
Posted October 2024
Ductless Mini Split Systems
Ductless mini-split systems offer an effective, energy-efficient solution for heating and cooling in new homes. This bulletin provides an overview of ductless mini-split systems, their benefits, and best practices for installation in compliance with the North Carolina HERO code program standards.
Posted September 2024
Home Upgrade Impacts
The RNC Program provides incentives based on improvements to insulation and performance results. To help raters and builders understand the impacts of upgrades, this technical bulletin covers a short analysis on the impacts to home upgrades.
Posted August 2024
Ekotrope Reporting
HERO failures pose a recurring challenge for RNC program raters. In this technical bulletin, we delve into the intricacies of building reports that diagnose HERO failures beyond the scope of basic blower door or duct blaster assessments.
Posted July 2024
Modeling Basements and Crawlspaces
For accurate savings, raters must assess and model basements and crawlspaces with precision. This technical bulletin will cover best practices.
Posted June 2024
Blower Door Guide
As part of the RNC Program, raters should understand the best practices when testing whole home infiltration. This technical bulletin covers basic preparation for blower door testing, manometer configurations, and air leakage calculations.
Posted May 2024
DG-700 Manometer
The DG-700 Manometer is a widely adopted pressure measurement tool utilized by the DERNC Program. This technical bulletin contains a summary of the fundamental controls and functionalities of the DG-700 used when performing a leakage to outside and total leakage test.
Posted April 2024
Insulation Grading
This bulletin is intended to help newer Program participants better understand insulation grading by defining RESNET Standard for Grade I, II, and III insulation. Pictures are also provided as a reference to help raters identify issues behind the insulation to determine the grade.
Revised March 2024
Originally Posted January 2023
Advanced Framing
This Technical Bulletin will cover best practices with advanced framing techniques.
Posted February 2024
Spray Polyurethane Foam
This Technical Bulletin will provide safety consideration, how to measure the depth of foam insulation and calculate the approximate R-value. Spray polyurethane foam (SPF) is frequently applied in the residential construction industry due to its ability to provide continuity of the water control, air control, vapor control, and thermal control layers necessary for environmental separation.
Posted January 2024
Pivot Table Tutorial
This Technical Bulletin will provide instructions on how to generate a Pivot Table in MS Excel to analyze data about homes submitted to the DERNC incentive program.
Posted November 2023
Modeling Slab Insulation
This Technical Bulletin will cover modeling partially insulated slab perimeters, slab insulation grading, and derating slab insulation with large termite gaps.
Posted October 2023
Recommended EELC Courses
This Technical Bulletin highlights recommended courses in the Duke Energy RNC Energy Efficiency Learning Center.
Posted September 2023
Top Plate Sealing
Top plate gaskets such as foam sill seal gasket or canned foam top plate gasket, have the potential for large impacts on energy savings and incentives in the RNC Program.
Posted August 2023
Ceilings
Various aspects of the ceiling affect the home’s energy modeling and performance. Insulation, roof decks, and baffling should be noted and inspected by raters for the type and quality of the installation. This month’s technical bulletin will help raters identify insulation issues that can affect the rebate and serve as a guide for modeling of ceilings in Ekotrope.
Posted July 2023
Garages
Proper installation of insulation and air barriers in garages during the rough stage will help improve blower door performance at final testing and help builders get their maximum possible rebate in the Duke Energy RNC Program.
Posted June 2023
Duct Testing
Accurate duct testing and modeling is crucial to the Duke Energy RNC Program savings calculations. This technical bulletin will cover duct testing procedures and serve as a guide to help raters estimate duct location percentages in the field.
Posted May 2023
Field Safety
Safety covers a broad range of topics; however, this technical bulletin will address three safety concerns that impact Home Energy Raters (HERS) while performing inspections.
Posted April 2023
Diagnosing Blower Door Problems
One of the main requirements for the Duke Energy RNC rebate program is a blower door test result at or below 4.0 ACH50. This month’s technical bulletin will give guidance on diagnosing blower door problems when the test results are over 4.0 ACH50.
Posted March 2023
Slab Insulation
Quality installation of insulation at a home’s thermal boundary is essential to qualify for the Duke Energy RNC Program. This technical bulletin provides examples of the types of slab edge insulation and common issues found.
Posted February 2023
What is HERO Code
The Duke Energy RNC Program promotes the construction of highly efficient, better quality new homes. Homes submitted into the Program must perform above code minimum requirements. This technical bulletin will help define HERO Code requirements and incentive structures.
Posted December 2022
New SEER Minimum Efficiency Standards
The Department of Energy (DOE) is updating air conditioner and heat pump minimum efficiency standards beginning January 1, 2023. This technical bulletin will cover an overview of the change and the new standards for air conditioners and heat pumps.
Posted November 2022
Refrigerant Charge
To help raters understand the HVAC grading process, the RNC team is publishing a series of technical bulletins on the HVAC grading process. This third bulletin covers HVAC Grading Task 5, Refrigerant Charge using the Non-Invasive method.
Posted September 2022
Measuring Blower Fan Watt Draw
To help raters understand the HVAC grading process, the RNC team is publishing a series of technical bulletins on the HVAC grading process. This second bulletin covers HVAC Grading Task 4, Blower Fan Watt Draw using the Clamp On Watt Meter method. A future bulletin will cover the reaming task, refrigerant charge.
Posted August 2022
Measuring Blower Fan Airflow
To help raters understand the HVAC grading process, the RNC team is publishing a series of technical bulletins on the HVAC grading process. This first bulletin covers HVAC Grading Task 3, Blower Fan Airflow using the OEM Static Pressure Table method. Future bulletins will cover the reaming tasks.
Posted June 2022
Duke Energy Carolinas RNC Expansion FAQs
With the news earlier this month of Duke Energy Carolina’s expansion in North Carolina, May’s technical bulletin will outline how to calculate estimated incentives using the DEC incentive structure. We have also provided some of the Frequently Asked Questions (FAQs) and their answers.
Posted May 2022
Dropped Ceiling Complexities
Dropped ceilings are an aesthetic feature used by designers to add depth to a room, but can create some complexities when it come to air barrier, air sealing and insulating. The complexities can lead to increased blower door results and a decreased incentive. This technical bulletin will help raters and builders identify what to look for when air sealing and insulating dropped ceilings.
Posted April 2022
Laundry Room Air Sealing
An often overlooked but common source of air leakage is the laundry room. The pre-drywall stage is the best time to perform cost-effective air sealing measures. This months technical bulletin will highlight best practices for air sealing the laundry room during the pre-drywall stage and offer guidance to diagnose leakage at final testing.
Posted March 2022
Final Inspection Guide
It is important for home energy raters to test home in the RNC Program correctly to ensure accurate rebates. This technical bulletin outlines testing procedures as well as incentive requirements for Program homes.
Posted February 2022
NCBPA Air Sealing Study
The North Carolina Building Performance Association (NCBPA) performed an air sealing study to analyze how builders and raters understand both The RNC Program and the best air sealing methods. This technical bulletin covers the air sealing aspects of the study.
Posted January 2022
Common Issues at Rough
This bulletin discusses the most common issues found during rough inspections during 2021 by the RNC team and provides tips for some common problem areas.
Posted December 2021
Insulation Grading
This bulletin is intended to help newer raters grade insulation by defining RESNET Standard for Grade I, II, and III insulation. Pictures are also provided as a reference to help raters identify issues behind the insulation to determine the grade.
Posted November 2021
Duct Testing
This bulletin covers how to diagnose problems with ducts that have leakage higher than 3.00% or that cannot pressurize.
Posted October 2021
Dual Fuel Heat Pumps & AHRI Database
Dual fuel Heat pumps are a rare sight in the RNC Program and can be tricky to model. This bulletin provides an example of how to model one in Ekotrope as well as how to navigate the AHRI database.
Posted September 2021
Rater Webinar: T-ply and House Wrap Best Practices
RNC Program Webinar on best practices and pros and cons for installing t-ply and house wrap.
Posted August 2021
Ekotrope Data Entry
Homes submitted in the RNC Program should be accurately modeled in Ekotrope. Small overlooked and mismodeled items can lead to compounded losses in savings, this bulletin covers slabs, floors and walls data entry.
Posted August 2021
Hot Weather Safety
As we enter the middle of the summer and are having heatwaves across the United States, the Duke Energy RNC Program wants to inform our partners about some hot weather safety and heat related illness safety precautions.
Posted July 2021
Blower Door Applications: Wind Assist and TEC’s Gauge App
The Energy Conservatory or TEC has updated their TEC Auto Test app to include a wind assistant feature. This new feature allows more accurate blower door results when the weather is windy. In addition to the wind assistant, this technical bulletin will introduce TEC’s gauge app which allows raters to remotely control the blower door.
Posted June 2021
Top Plate Sealing
Top plate gaskets such as foam sill seal gasket or canned foam top plate gasket, have the potential for large impacts on energy savings and incentives in the RNC Program.
Posted May 2021
DG-1000 Manometer Functions
The newer DG-1000 Manometer is becoming increasingly more popular in the RNC Program. This technical bulletin is a guide for the basic functionality of the DG-1000.
Posted April 2021
HVAC Grading in Ekotrope
The new Standard 310 (Std. 310) provides a method for evaluating the installation quality of HVAC systems. This technical bulletin outlines the steps for completing HVAC grading in Ekotrope.
Tech Bulletin Posted March 2021
Rater Webinar Posted April 2021
Thermoply Installation
Proper air barrier installation is vital when building a tight home. This technical bulletin will cover instructions for T-ply installation based on the manufacturer’s specifications.
Posted February 2021
Slab Insulation
Quality installation of insulation at a home’s thermal boundary is essential to qualify for the Duke Energy Progress RNC Program. This technical bulletin provides examples of the types of slab edge insulation and common issues found.
Posted January 2021
Air Barriers and Sealing Best Practices
Air barriers and sealants have the potential to make a large impact on homes in the RNC Program. To ensure homes receive their maximum incentives, raters and homebuilders should follow the air barrier and sealing best practices outlined in this technical bulletin.
Posted November 2020
Townhome Air Sealing
Townhome air sealing is one of the top issues found in RNC Program inspections this year. This technical bulletin will cover the top tips for air sealing townhome core walls.
Posted October 2020
Most Common Issues
Over the past year the RNC Program has compiled a list of the most common issues found at pre-drywall quality assurance inspections. This technical bulletin outlines those issues along with tips to address them during rater inspections.
Posted September 2020
Insulation Grading and Top Plate Gaskets
This technical bulletin covers some frequently overlooked items that raters should check when inspecting insulation and canned foam top plate gasket installation.
Posted August 2020
Equipment Calibrations
Accurate testing for all HERS ratings depends on properly calibrated equipment. This Tech Bulletin will discuss the processes for checking field equipment.
Posted July 2020
Rater Photo Library
To help raters communicate issues, this technical bulletin will outline resources the RNC Program is offering raters to incorporate into inspection results.
Posted June 2020
Blower Door Testing Tips
This Technical Bulletin provides general blower door testing tips and best practices for the TEC AutoTest App to conduct better quality inspections.
Posted May 2020
Construction Safety Tips
This Technical Bulletin overviews safety tips that may prevent injury or harm when working on a construction site.
Posted March 2020
Incentive Analysis
This Technical Bulletin details the process to determine various options a builder can use to maximize their incentive.
Posted February 2020
HERO Compliance Guide
This Technical Bulletin outlines the HERO and HERO + Hers incentive structures and best practices to meet HERO compliance.
Posted November 2019
Ekotrope Guide
This Technical Bulletin serves as a basic guide for using Ekotrope and understanding the results for determining RNC Program compliance.
Posted October 2019
Recommended EELC Courses
This Technical Bulletin highlights recommended courses in the Duke Energy RNC Energy Efficiency Learning Center.
Posted September 2019
Commonly Overlooked Items
This Technical Bulletin highlights the most commonly overlooked issues that impact HERO performance and incentives, along with error prevention methods.
Posted July 2019
Spray Foam Safety
Spray polyurethane foam (SPF) has gained popularity in the residential construction industry with its ability to expand into gaps and cracks, resulting in an effective air seal and insulator. This technical bulletin shows safety procedures when using SPF.
Posted June 2019
The Six-Sided Wall
Missing air barriers cause the largest portion of air leakage and thermal loss in the home. This technical bulletin shows the concept of the “six-sided wall” to help identify missing air barriers.
Posted May 2019
Plan Review Tool
In an effort to make plan take-offs easier and more consistent, ICF created a plan review tool with excel. This technical bulletin shows how to use the plan review tool.
Posted April 2019
Data Verification for Submitted Homes
The RNC Program requires verified addresses, climate zones, orientations, and permits. This technical bulletin shows best practices on verification.
Posted March 2019
Properly Air Sealing Tray Ceilings
It is critical to ensure proper air sealing throughout the entire home to meet infiltration requirements and ensure grade I insulation. This technical bulletin shows best practices when air sealing tray ceilings.
Posted February 2019
Diagnosing HERO Compliance
Chasing down the causes of a HERO code failure can be tricky, especially when using the standard code compliance reports available in Ekotrope and REM/Rate. This technical bulletin for raters is a short review of the best method available for identifying issues with HERO compliance.
Posted December 2018
Air Sealing Checklists for Builders
The PDFs available below are thorough checklists for builders as they inspect the work of their trades. Items are organized by area: floors, walls, ceilings, HVAC/ducts. A section dedicated to post-drywall items is also provided to help you “hunt for CFMs”, if your blower door is coming in a little too high.
Posted December 2018
DG 700 Manometer Functions
The DG-700 Manometer is the most commonly used pressure measurement device by RNC Program raters. This is an outline of basic DG-700 controls and functions.
Posted November 2018
Blower Door Testing in the Wind
Severe wind can be a difficult challenge to overcome when performing accurate infiltration tests. In fact, conducting infiltration tests on days with wind speeds exceeding 20mph is not recommended. This technical bulletin offers tips on adjusting to moderate levels of weather interference when conducting blower door tests.
Posted October 2018
LED Lighting
Ekotrope and REM/Rate recently released versions that include the ability to capture LED savings. LED lights can produce high-quality instant-on lighting with as little as half the wattage of a CFL, translating to larger rebates in the RNC Program.
Posted September 2018
Conducting an Automated Multi-Point Blower Door Test
Proper multi-point blower door testing is now more important than ever with RESNET Standard 380 coming into effect. This technical bulletin offers guidance multi-point blower door testing using the TEC DG-700 manometer paired with the TEC Wi-Fi link.
Posted August 2018
Infiltration Testing Correction and Standard 380
Std. 380 requires that single-point blower door tested CFM be corrected by +10% (ex. - if single point tested CFM = 100, modeled CFM must = 110). This bulletin briefly covers options for conducting multi-point testing.
Posted June 2018
Rater Field Guide Reminders
The RNC Program maintains guidance for raters on the Program's Rater Field Guide page. The technical bulletin below covers some highlights that all raters should keep in mind when modeling and submitting homes to the RNC Program.
Posted May 18, 2018
Blower Door Testing and Std. 380
ANSI/RESNET/ICC Standard 380 will soon replace Chapter 8 of the RESNET MINHERS Standard on how to conduct building and duct leakage testing and must be followed by all HERS Raters and RFIs for homes permitted on or after July 1, 2018.
Please follow the link below for the full technical bulletin.
Created April 10th, 2018
Grading Insulation Installation
Grading Insulation depends entirely on the quality of installation. For information on insulation grading, click on the link below.
Created April 3rd, 2018
Duct Leakage Testing and Standard 380
Effective July 1, 2018 (permit date), all program homes must follow the testing guidelines that have been updated in RESNET Standard 380.
Please follow the link below for the full technical bulletin that calls out the most important changes to the standard.
Created March 2018
Flexible Vs. Rigid Air Barriers
Proper air barrier installation is one of the key details that must be implemented consistently to meet the 4.0 Air Changes per Hour (ACH50) requirements for HERO Code.
For details on best practices, click below to download the full technical bulletin as a PDF.
Created February 2018
RESNET/ICC Standard 380
ANSI/RESNET/ICC Standard 380 has replaced Chapter 8 of the RESNET MINHERS Standard on how to conduct building and duct leakage testing and must now be followed by all HERS Raters and RFIs.
For details on how this will impact the Duke New Homes Program, click below to download the full technical bulletin as a PDF.
Created January 2018
Modeling Advanced Framing
REM/Rate accepts inputs that describe the "framing factor" of a building component. This bulletin provides best practices for capturing the benefits of advanced framing in walls and ceilings.
Click below to download the full technical bulletin as a PDF.
Created October 2017
Advanced Framing
Advanced framing is a term used to describe a number of methods that help builders use less framing material without compromising structural requirements in new homes. Using advanced framing opens up more space for insulation, which helps builders increase their HERO compliance rate and incentives.
Click below to download the full technical bulletin as a PDF.
Created September 2017
Post-Drywall Air Sealing
Trim out presents some good opportunities to make up for missed air sealing... and some possible stumbling blocks. View the full technical bulletin below for a full list of post-drywall air sealing hot spots.
Created August 2017
Update to Slab Edge Insulation Guidance
Slab edge insulation remains a critically important detail for most homes built on slabs. The recently updated guidance for stem wall applications provides an acceptable pathway to claiming this savings measure.
Created June 2017
Top Plate Air Sealing
The most common cause of HERO code failure is missing the required 4 ACH50 blower door target. Properly air sealing top plates on every home's upper floor is one of the most effective methods for increasing your pass-rate (and ensuring that your homes get the best rebates). The full technical bulletin below covers common top plate mistakes and fixes that are applicable in all home types.
Created May 2017
Slab Edge Insulation
Slab edge insulation plays a critical role in complying with the NC HERO code in all climate zones. While it is possible to forgo this measure and then trade off in other areas of the performance path metric, slab edge insulation is much easier, more cost effective, and creates more comfortable homes.
Created April 2017
Townhouse Air Sealing
Just like in single-family detached homes, whole-home air sealing in townhomes is critical to qualifying for rebates in the Duke Energy Progress RNC Program.
Click below to download the full technical bulletin as a PDF.
Created March 2017
Air Sealing - Top 5
Whole-home air sealing is a critical part of qualifying for the highest rebate incentives offered through the Duke Energy Progress Residential New Construction (RNC) Program. To qualify for Whole Home Incentives larger than $750, homes must come in under four air changes per hour (ACH).
Click below to download the full technical bulletin as a PDF.
Created February 2017
Efficient Lighting
Efficient lighting, including CFLs and LEDs, is the quickest and easiest way to increase your savings and rebates in the HERO+HERS incentive pathway. Click below for the full technical bulletin.
Training Manual: Townhouse Air Sealing
The training manual below expands on the topics covered in the RNC Program's technical bulletin on the same topic. This 3-step manual walks through the process of preventing uncontrolled infiltration in townhomes and includes descriptions and visuals for specific problems and solutions. Many of the solutions also apply to single-family detached housing.