St. Louis First Missouri City to Adopt 2018 ICC Codes

St. Louis adopts all ICC codes

The City of St. Louis became the first municipality in Missouri–and one of the first nationwide–to adopt the 2018 suite of codes by the ICC.

Habitat for Humanity home under construction at 3436 Indiana. Photo: Jessica Deem

As reported by Jessica Deem in NEXTstl,  the new codes are a major upgrade from the 2009 codes previously being used in the city of St. Louis and will significantly improve energy-efficiency requirements for new residential and commercial buildings as well as major renovations:

The city typically waits for St. Louis County to take the lead on code adoption, but this time the city decided to lead rather than follow, not only by becoming the first, but by introducing the 2018 Energy Conservation Code without major amendments. Previous versions of the city codes heavily amended the insulation and air-sealing requirements in the Energy Conservation Code. The adopted 2018 codes uphold the original code language for commercial insulation requirements. The residential insulation requirements include just two major amendments – the omission of basement insulation and reduction of ceiling/attic insulation from R-49 to R-38.

Amendments to the residential code were a compromise between the Missouri Sierra Club and the Home Builders Association of St. Louis and Eastern Missouri. Both organizations, along with members of The St. Louis Energy Coalition, provided input to the city’s Building Division and Public Safety Committee during the lengthy planning process.


  • 2018 International Building Code (Board Bill 53 / Ordinance 70794) 
  • 2018 International Energy Conservation Code (Board Bill 58 / Ordinance 70799)
  • 2018 International Existing Building Code (Board Bill 56 / Ordinance 70797)
  • 2018 International Residential Code (Board Bill 54 / Ordinance 70795)
  • 2018 International Mechanical Code (Board Bill 59 / Ordinance 70800)
  • 2018 International Property Maintenance Code (Board Bill 57 / Ordinance 70798)
  • 2018 International Fuel Gas Code (Board Bill 60 / Ordinance 70801)
  • 2018 International Fire Code (Board Bill 55 / Ordinance 70796)
  • 2017 National Electrical Code (Board Bill 61 / Ordinance 70802) 

Members of The Sierra Club and St. Louis Energy Coalition provide input on codes.

In addition to energy conservation, the 2018 Existing Building Code appears to introduce another major change from previous versions, in that more stringent compliance for electrical, mechanical and plumbing systems kick in at a lower threshold (Level 2 Alterations, rather than Level 3 alterations).

2018 Existing Building Code Levels of Alterations:

  • Level 1 alterations include the removal and replacement or the covering of existing materials, elements, equipment, or fixtures using new materials, elements, equipment, or fixtures that serve the same purpose.
  • Level 2 alterations include the reconfiguration of space, the addition or elimination of any door or window, the reconfiguration or extension of any system, or the installation of any additional equipment.
  • Level 3 alterations apply where the work area exceeds 50 percent of the building area

Under the new 2018 codes, if electrical, mechanical or plumbing systems are modified or extended in existing buildings, it appears they will now be required to be brought up to standards similar to new construction instead of being “grandfathered in.” This has the potential to increase construction costs significantly for Level 2 alterations, especially for small businesses and commercial owner-occupants that typically do more piecemeal upgrades to save money instead of replacing entire systems all at once.

The Existing Building Code section on Energy Conservation will remain in place, meaning full compliance with the new insulation and air-sealing requirements will be limited to Level 3 alterations, in which the work area exceeds 50 percent of the building area. A request for clarification from the Building Division is pending.

Read the full post here.



Photo by digitizedchaos