# Smoke alarms in existing homes



## Rick18071 (Feb 21, 2017)

Could someone tell me why according to 2009 IRC R314.3.1  smoke and CO2 alarms are required in existing homes when a simple  job like adding a new outlet or a new door but only CO2 alarms are required when installing a whole new HVAC system or wood stove?

*R314.3.1 Alterations, repairs and additions*.
When alterations , repairs or additions requiring a permit occur, or when one or more sleeping rooms are added or created in existing dwellings , the individual dwelling unit shall be equipped with smoke alarms located as required for new dwellings .
Exceptions:
1. Work involving the exterior surfaces of dwellings , such as the replacement of roofing or siding, or the addition or replacement of windows or doors, or the addition of a porch or deck, are exempt from the requirements of this section.
2. Installation, alteration or repairs of plumbing or mechanical systems are exempt from the requirements of this section.

*R315.2 Where required in existing dwellings.*
Where work requiring a permit occurs in existing dwellings that have attached garages or in existing dwellings within which fuel-fired appliances exist, carbon monoxide alarms shall be provided in accordance with Section R315.1.


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## CityKin (Feb 21, 2017)

If you read the sections you quoted, I think they are both triggered by any work requiring a permit.

However, R314.4 exception 2 allows that the smoke detectors just be battery powered and not-inter connected unless the drywall in the area is being removed.  CO detector are always allowed to be battery only, so the requirement is very easy to meet, just buy some cheap battery detectors and stick them to the ceiling.


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## cda (Feb 21, 2017)

On co only,  assumed smoke alarms are already installed??

Hvac work more associated with co??


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## steveray (Feb 21, 2017)

Bad code language?


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## cda (Feb 21, 2017)

steveray said:


> Bad code language?





steveray said:


> Bad code language?




Never...


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## Rick18071 (Feb 23, 2017)

I was just wondering why the required smoke alarms have exceptions but CO2 alarms don't. Sometimes I like to make sense of the codes. I also like to have an answer when a contractor or owner asks me.


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## cda (Feb 23, 2017)

Ok now I am lost on your question

Can you restate


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## Pcinspector1 (Feb 23, 2017)

Some things just make no since at all.

Joey! "Ever been in a Turkish prison before?"


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## cda (Feb 23, 2017)

Appears they cleaned it up in newer editions


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## Francis Vineyard (Feb 24, 2017)

deleted; double post


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## Francis Vineyard (Feb 24, 2017)

Rick18071 said:


> I was just wondering why the required smoke alarms have exceptions but CO2 alarms don't. Sometimes I like to make sense of the codes. I also like to have an answer when a contractor or owner asks me.





CityKin said:


> If you read the sections you quoted, I think they are both triggered by any work requiring a permit.
> 
> However, R314.4 exception 2 allows that the smoke detectors just be battery powered and not-inter connected unless the drywall in the area is being removed.  CO detector are always allowed to be battery only, so the requirement is very easy to meet, just buy some cheap battery detectors and stick them to the ceiling.



Receptacle plug in detectors are also available.


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## mtlogcabin (Feb 24, 2017)

Nobody around here reads a code book so they are required anytime a change out is made to a gas water heater or gas furnace.


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## ICE (Feb 24, 2017)

CityKin said:


> If you read the sections you quoted, I think they are both triggered by any work requiring a permit.
> 
> However, R314.4 exception 2 allows that the smoke detectors just be battery powered and not-inter connected unless the drywall in the area is being removed.  CO detector are always allowed to be battery only, so the requirement is very easy to meet, just buy some *cheap* battery detectors and stick them to the ceiling.



No such thing as a legal, cheap alarm here in California.


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## ICE (Feb 24, 2017)

mtlogcabin said:


> Nobody around here reads a code book so they are required anytime a change out is made to a gas water heater or gas furnace.


It's the same here as far as reading a code book and if I have to knock on the door, alarms are required.


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