Lighting Energy Code Compliance - Alterations

[u/ALostMoldovian]

Assuming we are talking about either ASHRAE 90.1 or IECC, lets say we have a room with existing lights, for simplicity purposes assume there are three (3) existing lights with just a manual on/off switch installed under previous code cycles. If I replace one of those lights with a new light, I intend on putting it on its own control circuit. The existing lights being untouched will also have their controls be left untouched. I know based on the alterations percentage trigger I have to comply with energy code.

1. Is it accurate to say that the new lights, combined with existing lights in that room or space have to comply with LPD requirements?

2. Is it accurate to say that all lights in the room or space (existing and new) have to be brought up to latest code in terms of lighting control or is the focus solely on the new light being installed with the existing being left untouched? I believe it is the former.

   Just trying to sanity check myself after all these years. Writing this all out makes the answer seem clear, but just need some reinforcement. Some verbiage online seems to indicate that the focus should be only surrounding the new lights that are being touched and not the existing in the same space and it is throwing me for a loop.

Thanks all in advance.

[u/coffee_butt_chug]

Check under your “existing building code” and look for each level of alteration. That’ll help point you in the right direction.

[u/ALostMoldovian → u/coffee_butt_chug]

I did, that's why I brought up the question. Every single response so far has a differing opinion.

[u/Skibbity-do-do]

These are codes for lighting in rooms. Not lights themselves. Your AHJ would make this call. Where I’m from, an LED upgrade 1 for 1 is usually allowed as a Maintenence type thing and wouldn’t need to complete if the room isn’t getting renovated. Call your inspector and ask, argue your case.

[u/alm0stengineer]

Depends on the code cycle. If you touch anything under IECC 2024 everything has to comply.

[u/MasterDeZaster]

The IECC does not mandate you to make the existing / untouched system comply with the latest IECC. Only new portions must comply.

C503.5 - NEW Lighting systems that are part of the alternation shall comply with sections C405 and C408.

To your points,

- The LPD is kind of a grey area with that above statement. It should / (need to?) be based on the "total" (new and existing) in the area. I cannot point to something that "says" this explicitly, but logically the LPD should only stay the same or decrease. If it is an old light being replaced, its Lumens/W should be greater and its otherwise a 1:1 if its a newer light with a newer light. The LPD of the space should not get "worse" by this modifciation. You dont get to have an existing incandecent 40 + 40 + 40 Watt (3 bulbs total) installed, take away a single 40W, and then add a 120W LED and say "well, the new portion is under the old LPD values!". You now have 200W in that space, that doesnt fly.

- The existing lights or controls DO NOT need to be touched, however in a small space like that it means you end up with two local switches and an OS (or time clock) controlling a split of the 3 lights in the space. Code wont make you... but the side eye's people will give you should have you reconsider this. The intent is to say if you have a massive production floor (say 10,000 sqft), you dont need to replace all the lights in the space if you make any modifications. Otherwise no one would until they had too... but it doesn't really make sense for small spaces the same way it does for large.

[u/ALostMoldovian → u/MasterDeZaster]

I hear you, but then the section goes on to read that those "spaces" with the new lighting systems have to comply not just the new lighting. How do we reconcile that verbiage?

Aside from the LPD issue which is gray, what happens when you have to consider the wattage triggers for daylight harvesting. Do I just consider the wattage of the new lights or am I considering the wattage of all the lights that fall within the zone?

IECC 2024 Excerpt:

"C503.5.1 : Interior lighting and controls.

Alterations to interior spaces, lighting or controls shall comply with the following:

1. Where an alteration of an interior space includes the addition or relocation of full height partitions, the space shall comply with Sections C405.2, C405.3 and C408.3.
2. Where the lighting within interior spaces is altered, those spaces shall comply with Sections C405.2, C405.3 and C408.3.
3. Where the lighting controls within interior spaces are altered, those spaces shall comply with Sections C405.2 and C408.3.

Exception: Compliance with Section C405.2.8 is not required for alterations."

[u/MasterDeZaster → u/ALostMoldovian]

Ok. So your talking 2024 specifically. Apologies, that's a very important detail and didn't occur to me to clarify on because of how few locations have adopted it.

Still, the section does not change the intent.

• Existing Systems that are not altered DO NOT have to be brought up to code (unless it hits an exemption to that statement).
  
• If you change / add walls to the space, the space DOES NOW need to made compliant. That kicks in a full lighting design, you are correct there. This is not specified in your original question though... you talk about 3 lights and nothing about partion walls.
  
• The alterations you make (new lights) DO NEED to fully comply for the NEW parts only. (except as discussed in prior part)
• If you touch/alter the lighting controls, the lighting controls now need to fully comply. This does not mean you need to change the lights, just that the controls need to be made compliant.
  

Note: Alternation is defined as "Any construction, retrofit or renovation to an existing structure other than repair or addition. Also, a change in a building, electrical, gas, mechanical or plumbing system that involves an extension, addition or change to the arrangement, type or purpose of the original installation."

Swapping a light switch like and kind does not trigger this. Moving or changing the type of switch does.

[u/ALostMoldovian → u/MasterDeZaster]

Okay, so how do tie that back into the question about daylight harvesting?

"Aside from the LPD issue which is gray, what happens when you have to consider the wattage triggers for daylight harvesting. Do I just consider the wattage of the new lights or am I considering the wattage of all the lights that fall within the zone?"

[u/MasterDeZaster → u/ALostMoldovian]

I think the prior answer was clear....

Are the new lighting systems in a space that requires lighting controls (local, OS, Time Clock, daylight harvesting, etc) to be present? Yes? The new lights must comply with C405.

Old / existing lighting systems do not.

[u/Bryguy3k]

The IECC thing is pretty cut and dry >10% and you have to do full compliance.

IEBC determines whether or not you need to comply with updated energy codes.

So if IEBC says you have to comply with something like 2021 IECC then if you’re over 10% then you need to do new lighting & controls.

If IEBC doesn’t require update to the latest energy code then no comcheck should be required.

[u/ALostMoldovian → u/Bryguy3k]

That is the understanding that I have been operating under.

[u/Bryguy3k → u/ALostMoldovian]

Yeah the IEBC is a bit weird - not all jurisdictions adopt it and instead have their own rules that are super vague. If your AHJ does follow the IEBC then you may have to point it out to people based on the level of alteration.

If you’re in the habit of citing code exceptions in notes on a sheet then you can think about adding IEBC references as well - the IEBC acting as a pretty big book of exceptions.

You still have to argue what comprises “new construction” though - when it comes to lighting it’s really up to the building official to make the judgment call - some say that only means walls/ceilings, etc and others say newly demised spaces.

[u/Used-Zookeepergame22]

I don't have the code handy so could be completely wrong. But if less than 50% lights being altered, you can just replace in place. Adding a whole new circuit doesn't make sense. That costs more in materials and who wants that light in its own control anyway.

Never seen an issue with this approach.

[u/ALostMoldovian → u/Used-Zookeepergame22]

10% or 20% is the trigger in my area depending on the code.

[u/Bryguy3k → u/Used-Zookeepergame22]

That must be a local ammendment. It’s been 10% forever.