[RE-wrenches] Fire Rating for Battery Room

[Jason Szumlanski]

One downside to this is that you are now potentially in a utility room
rather than a garage, and the capacity limit per NFPA might be 40 kWh
rather than 80 kWh.

I have yet to see an AHJ require an entire room/garage to be fireproofed,
but I am sure they would if they were clued in.


Jason Szumlanski
Principal Solar Designer | Florida Solar Design Group
NABCEP Certified Solar Professional (PVIP)
Florida State Certified Solar Contractor CVC56956
Florida Certified Electrical Contractor EC13013208


On Sat, Jun 7, 2025 at 12:01 AM Vince McClellan via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> One option to meet this code section is to build a battery room inside of
> a basement or other utility space with the proper fire rating.  It's not an
> inexpensive option, but it's often less expensive than drywalling the
> intire basement ceiling.
>
> And, as always, check with your AHJ before you move forward to ensure
> they'll pass the inspection on what you plan on building.
>
>
>
> Vince McClellan
>
> President
>
> NABCEP PV Professional
>
> p: 541-485-8122
>
> a: 860 Conger St. Suite 12,. Eugene, OR 97402
>
> e: vince at solarenergydesign.com <vince at solarenergydesgin.com>
>
> w: SolarEnergyDesign.com
>
> CCB# 161672
>
>
>
> If you have received this email and are not the intended recipient, please
> delete this email. Copying or using any part, content, or attachment of
> this email is strictly prohibited.
>
>
> On Fri, Jun 6, 2025, 11:12 AM Dave Angelini Offgrid Solar via RE-wrenches <
> re-wrenches at lists.re-wrenches.org> wrote:
>
>> Any thoughts from me would be not to have large batteries, unless
>> detached from the living space.
>>
>> There is a ship out burning full of electric cars in the Pacific today.
>> This is the 4th ship full of battery cars that I know of that has burned.
>>
>>
>> https://gcaptain.com/coast-guard-overflight-footage-reveals-fire-spreading-on-morning-midas-car-carrier-off-alaska-coast/
>>
>>
>>
>>
>>
>>
>>
>> *Dave Angelini Offgrid Solar
>> "we go where powerlines don't"
>>    <http://members.sti.net/offgridsolar/>https://offgridsolar1.com/ <https://offgridsolar1.com/>  <http://members.sti.net/offgridsolar/>
>> e-mail  offgridsolar at sti.net <offgridsolar at sti.net>
>> text 209 813 0060*
>>
>>
>> On 2025-06-06 6:17 am, Nicholas Ponzio via RE-wrenches wrote:
>>
>> For those of you installing batteries inside homes how are you treating
>> this poorly-worded section of Code?
>>
>> *NFPA 855 - 15.4.2:*
>> *If the room or space where the ESS is to be installed is not finished or
>> non-combustible, the walls and ceilings of the room or space shall be
>> protected with not less than 5/8 in. Type X gypsum board.*
>>
>> This section of fire code has given us much consternation over the years.
>> Most installations in this climate are going into unfinished basements. Are
>> you all installing 5/8 sheetrock for the entire basement? Just the area
>> around the batteries? Something else?
>>
>> Thanks in advance for any thoughts.
>>
>>
>> --
>> Nicholas Ponzio
>> Building Energy
>> 1570 South Brownell Road
>> <https://www.google.com/maps/search/1570+South+Brownell+Road+Williston,+VT+05495?entry=gmail&source=g>
>> Williston, VT 05495
>> <https://www.google.com/maps/search/1570+South+Brownell+Road+Williston,+VT+05495?entry=gmail&source=g>
>> http://www.BuildingEnergyVT.com <http://www.buildingenergyvt.com/>
>> "Building Solutions for a Sustainable Future"
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> Change listserver email address & settings:
>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>>
>> There are two list archives for searching. When one doesn't work, try the
>> other:
>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>>
>> List rules & etiquette:
>> http://www.re-wrenches.org/etiquette.htm
>>
>> Check out or update participant bios:
>> http://www.members.re-wrenches.org
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> Change listserver email address & settings:
>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>>
>> There are two list archives for searching. When one doesn't work, try the
>> other:
>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>>
>> List rules & etiquette:
>> http://www.re-wrenches.org/etiquette.htm
>>
>> Check out or update participant bios:
>> http://www.members.re-wrenches.org
>>
>> _______________________________________________
> List sponsored by Redwood Alliance
>
> Pay optional member dues here: http://re-wrenches.org
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Change listserver email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> There are two list archives for searching. When one doesn't work, try the
> other:
> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> http://www.re-wrenches.org/etiquette.htm
>
> Check out or update participant bios:
> http://www.members.re-wrenches.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20250608/392d791d/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 34f41ced.png
Type: image/png
Size: 955854 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20250608/392d791d/attachment-0001.png>