Way back in January, a few wise sages warned of the Changing of the Building Codes: they said “the City of Philadelphia’s new building codes will go live in July 2025,” referenced this document, and promised to “examine the 2025 code changes in depth as we get closer to July.” These same visionaries stayed quiet through July as absolutely nothing happened to the construction codes in PA or Philly.
But the administrative beast stirs! On October 16, 2025, an obscure PA commission finally approved regulations that will introduce new building codes to the Commonwealth (Philly included)! Philadelphia’s new building codes will be in effect on January 1, 2026, which means that… well, it means a few different things. Let’s review the code transition process and explain how it affects your 2026 construction projects.
Why Philly is Adopting New Building Codes
Building codes change because new construction methods and materials are constantly developed, while local and national governments (usually) enforce ever-stricter energy conservation and general safety standards (most of the time).
In the U.S., the main organization that creates model building codes is the International Code Council (not actually an international organization). Every three years, the ICC updates their codes for all types of construction (including plumbing, electrical, HVAC, and fire suppression work). States and cities, in turn, adopt versions of these codes for their use – typically with extra rules added on. These governments don’t have to update their codes at the same time as the ICC, but usually keep to some kind of update schedule.
Pennsylvania is mired in its own update process, but has finally completed the overall adoption of the 2021 version of the I-Codes – shorthand for the whole suite of ICC codes – with some changes to add spice. Collectively, the 2021 ICC and the PA amendments are the “Uniform Construction Code” (UCC) for the Commonwealth. Philadelphia, as it always does, will add even more local amendments to the UCC to govern any work in the city. When these changes are adopted, all new construction work – from small rehabs to new industrial projects – will have to abide by these newly-updated codes.
When the New Building Codes (Really) Take Effect
And so, like it says at the top, Philadelphia’s new building codes will be in effect on January 1, 2026.
But that’s not how it will feel to construction teams in Philadelphia. Here, the effective deadline to switch to the new building codes will be July 1, 2026. That’s because Philly’s Department of Licenses and Inspections won’t force any permit application to meet the new standards until six months after the official adoption date. L&I “will continue its practice of allowing a grace period during the transition between code editions. During this time, applicants may choose to have their projects reviewed under either the new or previously adopted code.” This means that until July 1st of ’26, you can apply for building permits in Philadelphia under the 2018 codes (as adopted by the City) or the 2021 codes.
Just to be clear: this is not how it works in the rest of Pennsylvania! In the other cities, townships, and boroughs of the Commonwealth, you must apply for a building permit under the 2021 codes starting New Year’s Day 2026 unless you can provide a construction contract dated before 2026. If you can provide such a contract, you can choose to proceed under the 2018 suite of codes adopted and amended by PA.
How Philadelphia Addresses Ongoing Code Updates
Philadelphia’s grace period makes it easier to plan for construction in the city than in the rest of Pennsylvania – at least during the first half of 2026. But all builders should be aware of two issues complicating Philly’s transition:
- L&I won’t allow permit applicants to mix codes
You’re not allowed to design some portions of your work according to the 2018 codes and other portions according to the 2021 codes. If you see areas in your design best served by 2018 provisions, while 2021 rules would be more convenient elsewhere, you just have to pick the version that works best for the overall project: you can’t mix and match code sections from different editions. - Philadelphia hasn’t completed its own amendments to the 2021 I-Codes as allowed under the PA Uniform Construction Code
If you decide to use 2021 codes before July 1, 2026, you’ll have to figure out which parts of those codes have already been amended by Philly, and which are still under review: the rules in March 2026 could be slightly different in May 2026 or June 2026.
Partly because of that second matter – the ongoing amendment process – a few codes straggle behind the main group, or just wander their own path.
Some codes referenced by the I-Codes are simply editions from different years to keep this suitably confusing. Case in point: the electrical and fire alarm standards used with the 2021 codes are (respectively) the National Electric Code (NEC) of 2020 and the National Fire Alam and Signaling Code (no fun abbreviation) of 2019 – and both of those codes are created by the NFPA, so they are also known as NFPA 70 and NFPA 72. This happens with every I-Code update: certain standards within the I-Codes are labeled with different years than the I-Codes, but this doesn’t indicate some local or regional amendment to the I-Codes of a given cycle.
Some amendments to the 2021 codes, however, are stewing at the state or local level, and we can’t be sure exactly when they will rise like steam from the paperwork broth.
For example, accessibility provisions – the rules that govern things like ramps and bathroom grab bars – are stuck on the 2009 edition, at least for the moment. Philly tried and failed to adopt the 2017 version of these rules in advance of the statewide (sorry, Commonwealth-spanning) code updates now underway. When a court struck down that attempt, Philly reverted to 2009 accessibility rules.
L&I’s code transition document summarizes the current state of play: “The accessibility provisions referenced in the 2018 International Building Code […] remain in effect until alternate provisions are adopted by the Commonwealth. This includes the referenced standard ICC A117.1-09 [the 2009 accessibility rules], Accessible and Usable Buildings and Facilities.” Those “alternate provisions” will be adopted by the Commonwealth, and soon: they’ll take on some version of the 2017 accessibility rules as part of their transition to the 2021 I-Codes. So by July 1, we should finally be working under 2017’s accessibility code, not the 2009 version; we just can’t name the actual date of transition, or how PA and Philly will tweak the standard. And this won’t be the only standard adjusted by those governments.
Still, while this code-amendment crossfire from Harrisburg to Philadelphia is disorienting, it’s not as dangerous as it seems: most projects in Philly won’t catch strays because most projects here will simply be reviewed as they have been the last several years (under the 2018 codes), right up to July ’26 when the 2021 codes and all their amendments are finally complete and enforced.
So just about any project designed to the current Philly building codes will be processed smoothly – if all permit applications are in review before July 1,2026. But this is not how all construction projects work: for one reason or another, some building permits will need to be amended after approval, or their related sub-permits – for scopes like HVAC installation – will be filed long after initial construction approval. And woe to those deferred applications or amendments filed on the wrong side of the new building code adoption date.
How Amendments and Trade Permits Are Treated During Transition
If you apply for a permit amendment after July 1, 2026, you can still use the old 2018 codes – so long as two criteria are met:
- The original submission must have been reviewed under the 2018 codes (obviously)
- The permit you’re amending must be issued already – you can’t try to revise a permit this way if you haven’t already paid for it and pulled it
This amendment rule does not apply to trade permits – meaning HVAC, electrical, plumbing, or fire suppression permits. If you want trade permits reviewed under the 2018 codes, those applications must be filed before July 1, 2026. If you’re not careful, you might have to revise a building permit filed under 2018 codes up to 2021 codes so that your trade permit designs can be integrated into the overall construction plan.
Similarly, all permits for Planned Unit Developments (PUDs) or similar, multi-phase projects designed under the 2018 rules must be filed before July 2026: even if the overall development plan – the “Master Plan,” as L&I calls it, feeling dramatic – was approved before July 2026, it will be considered invalid unless all the related permits are also filed before July 2026. So if you’re working on a PUD of 10 houses and they’re designed to satisfy the 2018 building codes, you need to submit applications for the overall development, the 10 houses, and each house’s trade work before July 1. If you can’t guarantee that, you should probably just design the PUD according to Philly’s new building codes.
What’s Actually in the New Building Codes
Now that you know all that, you might wonder: how will the new codes differ from the ones we have right now?
This question is way beyond the scope of a single post: the new building codes are biblically long, and in Philly at least they’re still not locked. So we don’t have anything more for you this time – but check this blog for additional posts about specific code changes! We’ll take you into the weeds, machete in hand.
And if you can’t wait that long, you can always drop us a line – we’d love to hear from you!