[GSBN] Fwd: [nbne] SB fireblocking

Fri Mar 21 03:22:31 UTC 2014

Hi,
We encountered this early on with an outside plan-checking engineer hired
by a small county. Ultimately we sat down with the chief building inspector
and pointed out the obvious--fire blocking is important in stud walls,
which would otherwise act as a chimney, but are not important in very dense
walls, such a bale wall in which fire cannot readily spread. All of Tracy's
suggestions are good, and common sense would say that making sure there are
not any channels in the wall through which a fire could spread should be
sufficient, however it's done.  The material does not have to be fire-proof
(2x blocking burns), it just has to stop the spread of flames. There is
plenty of data to show that bales will do that, and if they are
unconvinced, you can bring one to his office with a torch and ask him to
burn through it.

John

On Fri, Mar 14, 2014 at 9:28 AM, Tracy Thieriot <tracy at tactileplastering.com
> wrote:

> Hello Jim and EJ,
>
> I have dealt with this once on a project in Norther CA.  We installed
> plaster fire blocks in the walls and the top of the bale stack at the
> header.  Although the faces of the walls were lime plaster for the fire
> blocking we used a thick slurry of fireclay.  If you need something bulkier
> that will lay a plaster 1/2" thick.
>
> For the plaster prep we always stuff all bale holes, cavities and spaces
> where bales meet other materials (like partition walls) with light straw
> clay or other appropriately coated bulky material.
>
> If you have bale stackers that are willing to get muddy or anyone willing
> to smear mud you've got it covered and can install a thorough fire blocking
> - more so than with fiberglass or insulation.
>
> Best,
> Tracy Vogel Thieriot
> Tactile Plastering
>
>
> On Thursday, March 13, 2014, <ejgeorge at riseup.net> wrote:
>
>>
>> Hello folks,
>>
>> This comes from our NBNE list.  Jim Luckner who sent it, asked me to
>> forward to GSBN as well. He is working with an owner-builder on a house for
>> which the code officer is interpreting a need for fireblocking within the
>> straw bale wall to prevent fire from spreading through the wall cavity in a
>> HORIZONTAL manner. (The code also addresses fire-blocking in vertical
>> context, but that's not an issue in this particular design). The code
>> section in question comes from NYSRC which he assumes comes straight from
>> the IRC. The entire section is attached, but relevant parts:
>>
>>  R602.8 Fireblocking required.
>>
>> Fireblocking shall be provided to cut off all concealed draft openings
>> (both vertical and horizontal) ... Fireblocking shall be provided in
>> wood-frame construction in the following locations.
>>
>> 1. In concealed spaces of stud walls and partitions, including furred
>> spaces and parallel rows of studs or staggered studs; as follows:
>>
>>  1.1. Vertically at the ceiling and floor levels.
>>
>> 1.2. Horizontally at intervals not exceeding 10 feet (3048 mm).
>>
>>  AND
>>
>>  R602.8.1 Materials.
>>
>> ...fire blocking shall consist of 2-inch (51 mm) nominal lumber, or
>> [...other wood products, gypsum or cement board...]. Batts or blankets of
>> mineral wool or glass fiber or other approved materials installed in such a
>> manner as to be securely retained in place shall be permitted as an
>> acceptable fire block. ... Loose-fill insulation material shall not be used
>> as a fire block unless specifically tested in the form and manner intended
>> for use to demonstrate its ability to remain in place and to retard the
>> spread of fire and hot gases.
>>
>>
>> To the latter part, it would seem:
>> 1. the straw bales are being "securely retained in place" (he admits this
>> was a little vague in the drawings, but probably staked, attached to timber
>> frame posts, &/or wires interlocked). To my mind, any  bale wall stacked
>> tight enough to provide a good plaster base and avoid significant air
>> leakage - even if only primarily secured to each other - seems considerably
>> more secure than fiberglass batts tacked occasionally to studs.
>> 2. the straw bales, being baled are not "loose-fill" and even if they
>> were,  straw bale fire test results have shown them to demonstrate their
>> "ability to remain in place and to retard the spread of fire and hot gases."
>> Someone already sent him a copy of the 2006 ATSM 1 hour fire resistance
>> test for non-bearing strawbale wall, but if anyone else has additional
>> resources for him to use, or has successfully dealt with this issue before,
>> he'd love to hear of it.
>>
>> Jim's on this list as read-only, so you can reply to the group and he'll
>> see it, or reply to me & I can forward, or reply to him directly at the
>> email below.
>>
>> Thanks all!
>>
>> ej
>>
>> ej George, CSBA
>>
>> ----- Forwarded message from jimluckn at hvi.net -----
>>     Date: Wed, 12 Mar 2014 23:17:04 -0400
>>     From: Jim Luckner <jimluckn at hvi.net>
>> Reply-To: nbne at lists.riseup.net, Jim Luckner <jimluckn at hvi.net>
>> Subject: [nbne] SB fireblocking
>>       To: nbne at lists.riseup.net
>>
>> Hi:
>>
>>    I'm involved with a strawbale project under construction in midlands
>> of  code-crazy-New York, wherein the local building inspector is
>> interpreting section 602.8 of the  Residential Code to require horizontal
>> fireblocking  within strawbale walls  - that means breaking the running
>> bond and shoving a in continuous floor to floor strip of sheetrock or such
>> every 10 feet. I'm wondering if anyone else has had to deal with this
>> and/or know of any precedents in this regard.
>>
>> The building has 2 stories, with 2x6 inset studs + headers platform
>> framed to support roof load.  We have one section of wall on the ground
>> floor with inset interior 2x4 studs supporting the 2nd floor framing.  The
>> rest of the 2nd floor is supported on interior columns.  The finishes will
>> be plasters applied directly to the bale faces, with no furring and no
>> "concealed spaces" in the walls.  Some air movement is obviously possible
>> through the voids in the bales, though no more, i'd think, than through
>> fiberglass or mineral wool batts, which can be considered fire blocking
>> under the code.  The bales are unlikely to fall out of the wall unless
>> there's a partial or general collapse of the wood framing.  And, of course,
>> if bales are falling, they're not really falling out of the wall; the wall
>> is falling and any talk of "concealed draft openings" will be rather silly.
>>
>> -jim
>>
>> Jim Luckner
>> (845)658-3635
>> jimluckn at hvi.net
>>
>>
>>
>> - - - - -
>>
>> * NBNe email list home:
>> https://lists.riseup.net/www/info/nbne
>> * NBNe email list archive:
>> https://lists.riseup.net/www/arc/nbne
>> * NBNe email list shared documents:
>> https://lists.riseup.net/www/d_read/nbne/
>>
>> To access the above, you need a (free) riseup login for the subscribed
>> address. If you don't have a login, get one at http://riseup.net/
>>
>> Trouble? nbne-admin at lists.riseup.net
>>
>> - - - - -
>>
>> http://www.nbne.org
>>
>> - - - - -
>>
>>
>>
>> ----- End forwarded message -----
>>
>
> _______________________________________________
> GSBN mailing list
> GSBN at sustainablesources.com
> http://sustainablesources.com/mailman/listinfo.cgi/GSBN
>
>

-- 
John Swearingen
Skillful Means Design & Construction
2550 9th Street   Suite 209A
Berkeley, CA   94710
510.849.1800 phone
510.849.1900 fax

Web Site:  http://www.skillful-means.com
Blog:         https://skillfulmeansdesign.wordpress.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sustainablesources.com/pipermail/gsbn/attachments/20140320/9afc7c03/attachment.htm>