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2018 IECC – Officially Adopted in Illinois

Today Illinois starts it’s new fiscal year ushering in higher gas prices along with a ton of other fees & taxes. Also effective today, all newly permitted building work will have to follow the 2018 IECC as adopted. For those permitted before this date, you still fall under the 2015 version. Below are the final amendments approved by JCAR on June 11th.

  • 2018 Illinois Specific Amendments
  • 2018 Illinois Specific Amendments with Modifications Shown

For those of you in Chicago, well they actually started June 1st. While I have not had a chance to fully review their ordinance it appears to be a mirror of the Illinois version. What can one say, Chicago likes to think they are special & per the EEB Act…

  • Chicago Title 14N ordinance

So what’s this mean to…

For most individuals the only major change is the allowable Envelope Leakage Rate (Blower Door Test) has been lowered to 4 ACH. Yes that is still higher than what the code book show (3) but at least it is better than the 5 ACH allowed before. There is one exception & that is for some multi-family units where they can utilize the ELA option which can allow for higher leakage. (Helpful Tips: Blower Door Testing Checklist)

One other caveat is that your AHJ / Building inspector might not accept your HVAC installers Duct Leakage / Blaster Test Results & may insist on an independent third party.

For those using the ERI option – it has now gotten a little easier as the target number is higher. Along those lines the building department now has to accept it (was voluntary before) & the dreaded Myers BS factor is out.

While there are many other tweaks, we have covered the bulk of them before: 2018 IECC & Illinois – Where we stand (Sub Committee’s) & Pre-Commentary / Significant Changes

Some last minute changes made:

For those of you who have followed the Timeline & all associated pieces there was a few last minute tweaks made at the June 11th meeting:

…the rules do include the definition of Roof Membrane Peel and Replacement and the associated exceptions in both the commercial and residential sections C503.1 and R503.1.  They also include  Exception 8.  in C503.1 which states

8. Roof replacements for roof systems 2:12 slope or less shall comply with the low slope roof insulation requirements unless the installation of insulation above the structural roof deck, and necessary to achieve the code required R-value, is deemed infeasible by the code official to accommodate the added thickness of insulation above the roof deck. Conditions of infeasibility presented by due to flashing height limitations presented by existing rooftop conditions include, but are not limited to, flashing heights at HVAC or skylight curb, low door or glazing, parapet, weep holes, drainage patterns, due to cricket or saddle construction.  These conditions are subject to manufacturer’s specifications, manufacturers installation instructions and code official approval.  

The changes in red were made at the request of JCAR staff to make the language more clear.

 

Related posts:

2018 IECC - Illinois Board Approved Version

Illinois & the Fight over the ERI Path

Energy Code Basics: 3 Key Terms & Compliance Paths

BS4D: Building Codes

Monday Musings: 2021 IECC - Illinois Commercial Proposals

Alabama Energy & Residential Code

Notes from the field: Finding the leaks

Energy Code Basics: FAQ - State Wide Code Apply Locally?

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Filed Under: Building Codes July 1, 2019 By SLS

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