Priority Energy, Energy Code Assistance, IL

Need a Blower Test or Code Compliance help?

The State of Illinois is now enforcing the 2018 Illinois Energy Conservation Code for residential and commercial buildings.

New construction, permitted on July 1, 2019 or later, will be tested against these stricter guidelines.

Current construction projects, permitted before July 1st and completed by January 1st of 2020, will be tested under the old standard of IECC 2015. This is in accordance with the 6 month adoption window. If the project continues past 6 months (past January 1st), it will need to comply with the 2018 IECC standards.

Here is a link to the IECC 2018 code report showing where the changes were made.

NOTE: Blower Door or Air Tightness Tests must now measure 4 ACH50 instead of 5 ACH50. 

Our 3 Step Path to Illinois Energy Code Compliance

The path to IECC 2018 compliance is a simple 3 step process:

  1. Design the home's envelope

  2. Design the mechanical systems

  3. Inspect and test the house

Priority Energy is a recognized and trusted Chicago-area company holding the following ICC certifications; Residential Energy Inspector and Plans Examiner, Property Maintenance and Housing Inspector, Mechanical Inspector and Building Inspector.  We are a one-stop-shop for meeting all of the IECC energy code requirements for residential and commercial construction in Illinois.

STEP ONE: Choose Prescriptive, Performance or ERI Path to IECC Compliance

IECC Prescriptive Path

Work with your architect to ensure your plans reflect IECC 2018 insulation values, which can be found on our Energy Code Facts page.

IECC Performance Path (Simulated Performance – IECC 2018 Section R405)

You must have an energy model completed for the home by utilizing RESCheck or REM/Rate software to pursue the Performance Path. The benefit of following the performance path is you can utilize tradeoffs between insulation and air tightness, which often results in a better performing home that can be built at a more competitive price.

ERI Path (Energy Rating Index – IECC 2018 Section R406)

The Energy Rating Index path can be accomplished by hiring Priority Energy as your HERS Rater to create your HERS Index. Much like the performance path, this will allow us to create a performance model (which takes in to account all aspects of the house) to identify the highest performing home at the best price. Under IECC 2018, any home that scores a 54 or less for climate zone 4 or 55 or less for climate zone 5, is found to be in compliance with IECC 2018. 

There are other benefits to creating the HERS Index, including:

  • In Illinois, a HERS Index is required to take advantage of most rebates offered through   utility companies like COMED, NICOR, and AMEREN.

  • There is a federal tax credit available to builders if you meet efficiency requirements and have a HERS index created.

  • A HERS Index is a great way to market the energy efficiency of your home--it’s even on the MLS now in Illinois.

The RESNET-certified HERS Raters at Priority Energy will help determine your best strategy based on your goals and provide all necessary documentation for permitting.

STEP TWO: Have a Mechanical Sizing Completed For Your Home (IECC R403.7 – Equipment Sizing & Efficiency Rating)

With your path of compliance chosen and your building envelope decided upon, your next step is to procure an IECC-recognized mechanical sizing report. The most commonly-used reports for residential homes are an ACCA Manual J, ACCA Manual D, and ACCA Manual S report. In many instances, your mechanical contractor will offer to provide this report, but quite often, they are getting this sizing calculation from their equipment distributor for low or no cost. We recommend hiring a neutral third party to complete an unbiased recommendation.

A professional mechanical calculation report should include the following 3 components to be considered valid ACCA sizing:

ACCA Manual J

A complete Manual J will give you the total heating and cooling load (necessary for the ACCA Manual S – Equipment Selection) along with room-by-room loads (necessary for an accurate ACCA Manual D – Duct Design) so the installed system’s heating/cooling capacity can be appropriately distributed throughout the home to maximize comfort.

  • ACCA-approved software must be utilized for a manual J to be accurate. Click here for a list of approved software programs – Priority Energy utilizes the latest version of Wrightsoft Right J8 for all load calculations.

  • For complete details on what it takes to create an accurate Manual J, please see our HVAC Design & Testing - Residential page.

ACCA Manual S

A total block load created with the ACCA Manual J will provide the designer the total heat loss for heating, and the total heat gain (latent and sensible) for cooling. With the total heat load/gain, the designer will be able to select the exact furnace, AC/heat pump, and evaporator coil necessary to meet the home’s heating and cooling loads. This is required for permitting in the State of IL under the IECC 2018.

ACCA Manual D

An ACCA Manual D will give you a duct diagram from the furnace/air handler to the registers, including all ductwork, connections/fittings and registers. A duct system designed with ACCA-approved software will give you quiet airflow, extend the life of the furnace/AC, and decrease comfort complaints from the buyers/homeowners.

Click here to see a sample of a Mechanical Sizing Report as required for code compliance.

Priority Energy can provide ACCA Manual J/D/S reports within 48 hours (for an average 2,500 s.f. home). Our reports are accurate and priced competitively. Contact us to discuss your plans and get a quote today!

STEP THREE: Have All Required Inspections Completed

Under the IECC compliance codes, there are four inspections required:

     1. Air Barrier and Insulation Installation Inspection (IECC Table R402.4.1.1)

Depending on the village/town/city you’re building in, you may be required to have this inspection. The party who completes the inspection varies by where the home is being completed, so ask your builder or contact your city hall for specifics. Either way, this is a critical step to ensuring the home will meet the mandatory blower door test and occupancy requirements when completed. This will also help eliminate many future call backs related to comfort complaints and minimize building durability-related call backs (like drywall cracking and hardwood floor-related issues).

     2. IECC Duct Testing

     3. IECC Blower Door Test

     4. Home Ventilation Testing

All homes have to be provided with a ventilation system. Ventilation can be exhaust only (bath/kitchen fans with appropriate controls), supply only (intakes through the return ductwork of the furnace with appropriate controls), or balanced systems (ERV/HRVs). 

The system must meet the following requirements:

  • Meet or exceed a minimum ventilation rate of CFM total = 0.01CFA + 7.5(Nbr + 1) where the CFA = conditioned floor area and Nbr = number of bedrooms

  • Utilize ECM motors or meet a minimum ventilation efficacy

    • Fans <90 CFM = 1.4 CFM/watt

    • Fans=>90 CFM = 2.8 CFM/watt

    • Balanced HRVs/ERVs are an allowed exception and do not have to meet efficacy requirements.

Priority Energy can help you design, select and test your ventilation systems. Homes are being built tighter than ever, making this is a critical step to ensuring occupant safety and building durability.

See our Residential Ventilation Systems page for more information, or contact us to schedule an appointment.

Energy Code Facts

Priority Energy, Energy Code Facts, IL
With the adoption of the International Energy Conservation Code (IECC), home building and commercial construction has taken on an extra layer of complexity. The code is intended to increase the efficiency of the homes we’re building through added insulation, air sealing and other efficiency measures.

Blower Door Tests

Priority Energy, Blower Door Test, IL
Since 2012, blower door air leakage tests have become mandatory tests, regardless of the path chosen for compliance. The test consists of a large fan, which is installed on an exterior door of the home. The home is depressurized/pressurized to a difference of 50 Pascals, or 0.2 IWC with respect to the outside.

IECC Duct Testing

Priority Energy, IECC Duct Testing, IL
Since 2009, under the IECC Code, all ducts should be sealed, air handlers sealed, and duct tightness should be verified by a duct leakage test unless 100% of all ductwork is within the conditioned space. This means that any time you run a duct outside of the building envelope (in the attic, crawlspace or garage, for example), the system has to be tested.

IECC Energy Modeling

Priority Energy, IECC Energy Modeling, IL
An energy model, which is a computerized simulation of a home’s energy consumption, is used to compare energy-related components and test performance scenarios. This tool is especially helpful for predicting energy efficiency trade-offs, utility costs and the effects and payback of green energy solutions such as solar panels, photovoltaics, wind turbines and high-efficiency appliances.
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  • I have a two story home built in the mid seventies. Lots of temperature fluctuation between the floors. The Aeroseal process dramatically increased the air flow to the second floor. Good experience. The company was very informative, answered a lot of questions.

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  • "It's been cold here for the past few days and I really feel the difference in heating since the Aeroseal, my apartment is so much warmer now. Thank you!"  

    MP from Peru, IL
  • Thank You so much for the super-fast turn around of our Manual J, D and S reprt for the Village of Glen Ellyn. Our original Manual J kept getting kicked back to us for corrections but your calculations/report got approved instantly-no questions asked and no more permit delays!

    Kim, Glen Ellyn, IL
  • Thank you. Truly. I appreciate you taking the time to clarify things for me and then going above and beyond to ensure that my CEUs are handled for our current RESNET cycle. You’ve always been kind to me and this is another shining example of that.

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  • (Aeroseal) is a GREAT Product! Really made our townhouse more comfortable!

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  • Pat was awesome and super helpful! We are experiencing weak air flow in the duct system of our 1950''s home and Pat gave us great recommendations to fix the problem when we do our remodel.

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