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  1. #1
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    Default Ducts entering into the attic...

    Is ductwork supposed to have a fire stop when it penetrates into the attic from the living space below? Are there any exceptions where drywall can be missing from the floor, exposing the lower story (via chase)?

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  2. #2
    Ted Menelly's Avatar
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Marc M View Post
    Is ductwork supposed to have a fire stop when it penetrates into the attic from the living space below? Are there any exceptions where drywall can be missing from the floor, exposing the lower story (via chase)?
    Short answer....no. The chase is surrounded by drywall.

    What would be the difference with a supply or return vent in the ceiling.

    if it were a metal chimney flue then there would have to be a separation at ceiling level.


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    Default Re: Ducts entering into the attic...

    Other methods and materials besides gyp board (which is normally installed on the ceiling below, or the underside of the roof decking/supporting assembly, not the floor above); also depends on the floor/ceiling assembly. Unknown if FRT, mechanicals in attic, etc. No pics provided from below either.

    BTW how is the roof supporting assembly protected, separated? What type of roofing material?

    Blocking/stopping different terms. Fire/flame/smoke. Not enough information provided. What type of vent is pictured to the right? clearance? No insulation dam visualized in the photo.

    Last edited by H.G. Watson, Sr.; 08-01-2010 at 08:02 AM.

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    Default Re: Ducts entering into the attic...

    Ted's short answer.

    Jerry McCarthy
    Building Code/ Construction Consultant

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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Ted Menelly View Post
    Short answer....no. The chase is surrounded by drywall.
    Short answer ... yes.

    That is not a return air plenum, and, if it were, there would be PLENTY of deficiencies to write up, think something the size of War and Peace ...

    What would be the difference with a supply or return vent in the ceiling.
    That would make the ceiling area a return air plenum, see comment above as that would create a monster of a write-up.

    if it were a metal chimney flue then there would have to be a separation at ceiling level.
    The same thing applies here - there appears to be a metal vent or duct of some type to the right and flexible duct behind it, with more flexible duct to the left, that makes that a chase, just like you would have around "a metal chimney flue then there would have to be a separation at ceiling level" - and that is called fireblocking, not firestopping (as H. G. was referencing with the different terminologies).

    Short answer ... you should not be able to see that paper facing on the insulation as that should be fireblocked at the ceiling level, however, being as you can see that paper facing on the insulation you now get to write up at least two things: 1) no fireblocking at the ceiling; 2) exposed paper facing on the insulation which is required to be in contact with gypsum board or other approved building material. (Okay, so that answer was not so short. )

    Jerry Peck
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  6. #6
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Jerry Peck View Post
    Short answer ... yes.

    That is not a return air plenum, and, if it were, there would be PLENTY of deficiencies to write up, think something the size of War and Peace ...



    That would make the ceiling area a return air plenum, see comment above as that would create a monster of a write-up.



    The same thing applies here - there appears to be a metal vent or duct of some type to the right and flexible duct behind it, with more flexible duct to the left, that makes that a chase, just like you would have around "a metal chimney flue then there would have to be a separation at ceiling level" - and that is called fireblocking, not firestopping (as H. G. was referencing with the different terminologies).

    Short answer ... you should not be able to see that paper facing on the insulation as that should be fireblocked at the ceiling level, however, being as you can see that paper facing on the insulation you now get to write up at least two things: 1) no fireblocking at the ceiling; 2) exposed paper facing on the insulation which is required to be in contact with gypsum board or other approved building material. (Okay, so that answer was not so short. )
    Jerry

    Short answer....NO

    It is a chase and from what I see completely surrounded by drywall. There is no need to have the ceiling height closed off from the lower level to the upper level

    As far as how the duct work hooks up to supply vents or return vents and the drywall just has a hole cut in it for the vent to go thru the drywall..........whats your point.

    In this case unless something was not said in the original posters comments. it is just a duct running in a chase from the first floor to thew second floor. The ceiling does not have to be closed up. The drywall surrounding the chase is the same as the drywall on the ceiling.


    IFFFFFFFFF it where a flue from a fireplace and such then the ceiling height has to be closed off. In this case....no.


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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Ted Menelly View Post
    Jerry

    Short answer....NO

    It is a chase and from what I see completely surrounded by drywall. There is no need to have the ceiling height closed off from the lower level to the upper level

    Let me get this straight, you are saying, and insisting, that you can create a drywall chase and NOT fireblock it at the ceiling?


    Yet you are also saying that if you had a fireplace in that chase you would need to fireblock it at the ceiling?

    Make up your mind, you either do, or do not, need to fireblock that chase at the ceiling level.

    Jerry Peck
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    Default Re: Ducts entering into the attic...

    The liner on that larger flexible "duct" beneath the void in the plywood appears to be a conbustible covering.I see no insulation dam(s) for the opening in the attic "floor".

    We have not had questions answered regarding the "vent(s)" to the right. We have no details of the transition from the "ceiling" above (i.e. beneath what we can see and the floor/ceiling assembly from below. We do not know the elevations, etc.

    There are other materials besides gyp board which can be on the "chase" walls, assuming it is a "chase". We do not know if any of the lumber/wood is FRT. We do not know the details of the areas above, below, or aside. We do not know the height of the attic, or if any protection to the roof structure exists. We do not know the presence or not of other equipment or systems in the attic area. We do not know what this is an attic of. We do not know if there is a separation wall in the attic between for example an attached garage containing systems and the living area of the home, or between units.

    There is much we do not know, too few details, and no clear indications, with no responses to questions, so there really is no point making generalized statements to a detail/fact-fuzzy poorly worded (terms) VAGUE question which requires a series of presumptions to begin to respond to.

    Last edited by H.G. Watson, Sr.; 08-01-2010 at 10:44 AM.

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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Jerry Peck View Post
    Let me get this straight, you are saying, and insisting, that you can create a drywall chase and NOT fireblock it at the ceiling?


    Yet you are also saying that if you had a fireplace in that chase you would need to fireblock it at the ceiling?

    Make up your mind, you either do, or do not, need to fireblock that chase at the ceiling level.
    The fireplace has a particular purpose for closing it off at the ceiling it is called an open burning fire in the fireplace that can get out of control. There is not an gas fired or solid fuel fired appliance at the bottom of that chase. It is nothing more than taking those walls and tilting them up and having the block at the ceiling and not the walls. Yes I am saying that. There is abosolutely nothing wrong with it. The question was only about duct work coming up from the first floor. Not about insulation, fireplaces or anything of the like. My comments are souly based on that question. If a duct connects to a supply vent or a return vent in a ceiling there is absolutely no difference than that chase. This is a duct work question. If in fact there had to be drywall at the to[p of the chase then you would be saying that there has to be a fire damper at ceiling height as well. Again he was not talking of a gas or solid fuel fireplace at the bottom that this chase is for and he also mentioned nothing about the insulation being right or anything else for that matter.

    The way you are putting it

    if there is a hole in the ceiling anywhere and there is a duct on the other side of the ceiling?????????? What exactly are you saying.......Remember now. The question was for duct work as in HVAC system duct work. try not reading anymore than what he is asking. Address other issues as they come up.


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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Ted Menelly View Post
    The fireplace has a particular purpose for closing it off at the ceiling it is called an open burning fire in the fireplace that can get out of control. There is not an gas fired or solid fuel fired appliance at the bottom of that chase. It is nothing more than taking those walls and tilting them up and having the block at the ceiling and not the walls. Yes I am saying that. There is abosolutely nothing wrong with it. The question was only about duct work coming up from the first floor. Not about insulation, fireplaces or anything of the like. My comments are souly based on that question. If a duct connects to a supply vent or a return vent in a ceiling there is absolutely no difference than that chase. This is a duct work question. If in fact there had to be drywall at the to[p of the chase then you would be saying that there has to be a fire damper at ceiling height as well. Again he was not talking of a gas or solid fuel fireplace at the bottom that this chase is for and he also mentioned nothing about the insulation being right or anything else for that matter.

    The way you are putting it

    if there is a hole in the ceiling anywhere and there is a duct on the other side of the ceiling?????????? What exactly are you saying.......Remember now. The question was for duct work as in HVAC system duct work. try not reading anymore than what he is asking. Address other issues as they come up.
    How do YOU know what is or is not present?

    Do you not see the items to the right? How do YOU KNOW what functions they perform?

    I see what I believe to be plywood from the attic floor in contact with the metal tube and a void continuous to the irregular "hole".

    I cannot see through items photographed, how can you? (some sort of x-ray photoshop skills?)

    Where did fireplaces fall into this discussion? floor/ceiling assemblies and separations, blocking, draft-stopping are issues beyond just fireplaces.

    BTW I also see some interesting cabling/wire paths.



    Last edited by H.G. Watson, Sr.; 08-01-2010 at 11:01 AM.

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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by H.G. Watson, Sr. View Post
    How do YOU know what is or is not present?

    Do you not see the items to the right? How do YOU KNOW what functions they perform?

    I see what I believe to be plywood from the attic floor in contact with the metal tube and a void continuous to the irregular "hole".

    I cannot see through items photographed, how can you?

    Agreed

    I AM making assumptions but I am not addressing anything but ducts that go up a chase and again assunimg a one story single family home on slab (way to much assumtion)

    My one and only address is a chase from the floor below (again assuming first floor one story, single family that has a duct in it running to the attic.

    My point was what the heck is the difference with a drywall ceiling having a supply vent in it compared to a chase with a duct coming up in the attic

    Drywall ceiling......drywall chase.

    If one is addressing that a fire block at ceiling height is going to make one bit of difference with a flex duct that has a burn thru time of a second or so is any different than coming thru a drywall wall below?????????????????????? No difference.

    Now if you are talking a duct coming up from a chase below and there is another living unit above and you have no fire damper in it ten >>>>>>>>>>>> there is a bit of a difference


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    Default Re: Ducts entering into the attic...

    Ted,Look into the void. Do you not see paper in one of the "wall" stud cavities? Do you see nothing in the next right stud cavity?Now. It is very common in California homes with attached garages to have the HVAC heating equipment/air handler in the attached garage OR in a closet with access to and vented/louvers for combustion air the outdoors (sort of like common to mobile homes) in older multifamily units.The predominant heating is still GAS fired FA in California. Predominant fuel for clothes dryers is GAS in California. Poster is from...California, where in california we are left to guess. We see a large width rather deep irregular opening over an unknown elevation with unknown structure, separation, blocking, stoping, etc. characteristics, with a dinky piece of strapping at the left. We see an apparent kraft wall insulation combustible liner bulging from stud cavity below, adjacent to an apparent uninsulated cavity. We see cables or cords in two places, we have insufficient information or detail.Enough already, you aren't "getting" it.


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    Default Re: Ducts entering into the attic...

    Ted,

    I've been applying logic before I bring in the codes, so here is one final attempt at getting you to see the fallacy in your "logic".

    You are saying that a fireplace, be it a UL listed metal one of a masonry one - both of which have been designed and are intended to contain a fire ... needs to have the ceiling level fireblocked whereas a wall made of regular old drywall - which we KNOW WILL NOT contain a fire ... does not need to have the space fireblocked at the ceiling level.

    Using your theory then ... why is a stud wall required to be fireblocked at the floor and the ceiling?

    The reason the chase at a fireplace is required to be fireblocked has absolutely NOTHING to do with the fact that there is a fireplace in the chase or that the fireplace may ... that is correct ... "may ... but also "may not" have a fire in it. The reason that chase the fireplace is in needs to be fireblocked at the ceiling is that it is a concealed space and concealed spaces are required to be fireblocked at floor and ceiling levels.

    Using your theory, then, a fire breathing furnace would not be allowed to have combustion make up air duct go into the attic as, well, there is fire there and one would not want it to go up into the attic, yet the code actually allows - make that REQUIRES - those combustion make air ducts there.

    Please, think about what you are saying and the logic, er ... illogical aspect ... behind it.

    Then, when you have fully decided on which position you want to take, I (or someone else) will post the code which addresses this.

    Jerry Peck
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    Default Re: Ducts entering into the attic...

    Here is what the NC Residental Code says. It looks like #4 was added in the 2009 code. Note the I before the 4.




    R602.8 Fireblocking required.

    Fireblocking shall be providedto cut off all concealed draft openings (both vertical and horizontal) and to form an effective fire barrier between stories, and
    between a top story and the roof space. 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).

    2. At all interconnections between concealed vertical and
    horizontal spaces such as occur at soffits, drop ceilings
    and cove ceilings.

    3. In concealed spaces between stair stringers at the top and
    bottom of the run. Enclosed spaces under stairs shall
    comply with Section R311.2.2.


    I 4. At openings around vents, pipes, ducts, cables and wires
    at ceiling and floor level, with an approved material to
    resist the free passage of flame and products of combustion.

    5. For the fireblocking of chimneys and fireplaces, see Section
    RI003.19.

    6. Fireblocking of cornices of a two-family dwelling is
    required at the line of dwelling unit separation.

    R602.8.1 Materials. Except as provided in Section R602.8,
    Item 4, fireblocking shall consist of 2-inch (51 mm) nominallumber,
    or two thicknesses of I-inch (25.4 mm) nominal
    lumber with broken lap joints, or one thickness of 23/32-inch
    (18.3 mm) wood structural panels with joints backed by
    23/32-inch (18.3 mm) wood structural panels or one thickness
    of 3/4-inch (19.1 mm) particleboard with joints backed by
    3/4-inch (19.1 mm) particleboard, I/2-inch (12.7 mm) gypsum
    board, or I/4-inch (6.4 mm) cement-based millboard.
    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. Batts or blankets of mineral or glass fiber or
    other approved nonrigid materials shall be permitted for
    compliance with the 10 foot horizontal fireblocking in walls
    constructed using parallel rows of studs or staggered studs.
    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.

    R602.8.1.1 Unfaced fiberglass. Unfaced fiberglass batt
    insulation used as fireblocking shall fill the entire cross
    section of the wall cavity to a minimum height of 16
    inches (406 mm) measured vertically. When piping, conduit
    or similar obstructions are encountered, the insulation
    shall be packed tightly around the obstruction.

    R602.8.1.2 Fireblocking integrity. The integrity of all
    fireblocks shall be maintained.




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    Default Re: Ducts entering into the attic...

    Aren't getting it huh...cute

    Illogical logic....cuter.

    As far as a fireplace......seriously....it has nothing to do with being a fireplace...OK.

    Make up combustion air from attic.....never around here. It has to come from the exterior.

    I was addressing a duct maybe with a return or supply vent in the wall below. No the metal what ever vent pipe or Kraft faced insulation or anything else.

    A wall. with a duct in it. Leading to a completely enclosed shaft sitting on a floor.....you are concerned with the ceiling height area being closed off with drywall or what every. The duct has a burn thru time of about a second with any substantial heat. The flame goes thru and up the duct hole and burns the roof off and you are still worried about putting drywall around the perimeter of the duct above that completely enclosed shaft. You are going to save the roof burning off by........a couple seconds. Sounds good. Run with it.

    Like I said.....duct connection to return or supply vents in a ceiling.....where is the logic on that. And you want to not only have the wall drywalled that it is sticking thru but another circle of drywall around it that will do exactly what??????????????? Not a damn thing. The flames are still going to burn up and thru in the same amount of time.

    Assuming that this is lets just say a 2 foot by 2 foot shaft or so sitting on a slab. Stick a big hole in the wall. Put a return or supply vent and duct to it but lets enclose the ceiling height with another circle of drywall. Sounds more like you are just making it a better chimney to me causing a wonderful draft.

    I guess we don't really have to worry about that at all because there is more than a dozen holes in the ceiling throughout the home with just a duct attached to those holes that has a burn thru time of about a ............... second so the roof will burn off a second later. Fire heats up and gets to the ceiling and the temp of the flames is....how much...hundred, a thousand degrees or more.....poof. There goes the duct.

    So if the small chase is just for a duct. Well, you just made that duct slightly larger.

    Now, play nice and come back with logical thought on this or I might be nasty and yell at you. Then I might get scolded.

    I know what the code says but in just the case of a duct it in a small shaft completely enclosed with drywall it is just like a ceiling with one layer of drywall and a return or supply vent in it. It makes no damn difference.

    Coming up from a crawl or first floor or another living space above as in condo or etc etc etc etc etc etc Then there is a lot more to read into it.

    Remember, be nice.


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    Default Re: Ducts entering into the attic...

    James,

    Note R602.8.1.1., then 2., those two cover the space in the photo quite well.

    (red, bold, underlining are mine)
    Quote Originally Posted by James Duffin View Post
    R602.8 Fireblocking required.

    Fireblocking shall be provided to cut off all concealed draft openings (both vertical and horizontal) and to form an effective fire barrier between stories, and between a top story and the roof space. 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).

    2. At all interconnections between concealed vertical and
    horizontal spaces such as occur at soffits, drop ceilings
    and cove ceilings.


    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Ted Menelly View Post
    I was addressing a duct maybe with a return or supply vent in the wall below.
    That is one of the places you are incorrect.

    You are addressing:
    A wall. with a duct in it. Leading to a completely enclosed shaft sitting on a floor.

    Remember, be nice.
    Being real nice here ... You are referring to a chase "with a duct in it" (your words, see above quote) and NOT "addressing a duct" (also your words in the above quote).

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
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    Default Re: Ducts entering into the attic...

    one other reason for blocking in that area is to maintain the building envelope ill bet if you look down the chase the only wall insulated is the one you see in the picture and most likely that wall is the exterior wall leaving a very large opening in the envelope directly into the attic.


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    Default Re: Ducts entering into the attic...

    Sorry about not getting back, I was working. Buyers are getting weired with their available times etc... Must be this market.
    Directly below this area is the laundry room. The vent you see is a dryer vent which vents vertically to the exterior. The wire is from the thermostat because the FAU is next to me on my left. The duct is not a return. It is an 8 or 10 I believe that may supply a couple rooms below (I'm guessing).
    I understand that if there is a chase there still must be fire stopping with respect to fireplace vents but I was under the assumption that the entire ceiling must be closed up. Also, I'm in Los Angeles county.


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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Marc M View Post
    I understand that if there is a chase there still must be fire stopping ...

    Marc,

    I believe you mean "fireblocking" instead of "firestopping", and, yes, that chase needs to be fireblocked at the ceiling level, whether or not there is a fireplace in there.

    From the California Building Code. (bold and underlining are mine)
    - SECTION 717
    - - CONCEALED SPACES
    - - - 717.1 General. Fireblocking and draftstopping shall be installed in combustible concealed locations in accordance with this section. Fireblocking shall comply with Section 717.2. Draftstopping in floor/ceiling spaces and attic spaces shall comply with Sections 717.3 and 717.4, respectively. The permitted use of combustible materials in concealed spaces of buildings of Type I or II construction shall be limited to the applications indicated in Section 717.5.
    - - - 717.2 Fireblocking. In combustible construction, fireblocking shall be installed to cut off concealed draft openings (both vertical and horizontal) and shall form an effective barrier between floors, between a top story and a roof or attic space. Fireblocking shall be installed in the locations specified in Sections 717.2.2 through 717.2.7.

    - - - - 717.2.2 Concealed wall spaces. Fireblocking shall be provided in concealed spaces of stud walls and partitions, including furred spaces, and parallel rows of studs or staggered studs, as follows:
    - - - - - 1. Vertically at the ceiling and floor levels.
    - - - - - 2. Horizontally at intervals not exceeding 10.feet (3048 mm).
    - - - - 717.2.3 Connections between horizontal and vertical spaces. Fireblocking shall be provided at interconnections between concealed vertical stud wall or partition spaces and concealed horizontal spaces created by an assembly of floor joists or trusses, and between concealed vertical and horizontal spaces such as occur at soffits, drop ceilings, cove ceilings and similar locations.


    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
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    Default Re: Ducts entering into the attic...

    Thanks Jerry,
    I think i have the two words twisted.
    Where are you citing that from?
    Here is a pic of a fireplace vent, same situation.

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    Last edited by Marc M; 08-01-2010 at 07:49 PM.

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    Default Re: Ducts entering into the attic...

    Or these...

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    Default Re: Ducts entering into the attic...

    An example of "fireblocking" is the top plate on a wood stud wall. It "blocks" the passage of fire. Additionally, you may find "fireblocking" in a wood stud wall, used to be at 4 foot intervals, and is supposed to be tight fitting (to block the passage of flame) and to contain the fire within a small area in the wall. As I recall now, the area is 10 feet vertically and horizontally (i.e., measured horizontally on a vertical wall - an example of this would be a block wall with wood furring strips, at least every 10 feet vertically the space must be sealed off with the furring strips and at least every 10 feet horizontally the space must be sealed off with furring strips).

    In your photos, both of them, the top of those chases are required to be fireblocked at the ceiling level. The code addresses material suitable for use as fireblocking, wood used for fireblocking must be 2x in thickness, there are other materials allowed by the code for use as fireblocking.

    An example of "firestopping" is as listed UL design "firestop" which encompasses a specific set of components assembled in a specific way, i.e., let's say you have a concrete condo structure and the concrete floors are the fire separation between floors, and there are pipes which run vertically up through the floors, such as water pipes, DWV pipes, electrical conduits, etc. Those pipes and conduits now penetrate through the fire separation floor, and if they are not cast in place (most are not) then an opening is left in the floor for the pipes and conduits to be run through. Let's say the opening which was left is 6" x 12" and contains 4 3" pipes side-by-side-by-side (for this example). The rest of the opening is still open and needs to be "firestopped" to the same rating as required for the fire separation concrete floor. This "firestopping" can consist of many combinations of materials which were tested as an assembly and proved to stop fire from penetrating for a given amount of time, typically 1 hour, 2 hours, 3 hours, or 4 hours.

    The above are such basic examples and not all encompassing of fireblocking and firestopping. I guess one could think of fireblocking as a structural component used to stop the spread of fire and fireblocking as something one installs to seal off an opening and stop the spread of fire.

    From the IRC:
    - FIREBLOCKING. Building materials installed to resist the free passage of flame to other areas of the building through concealed spaces.

    With firestopping you have two distinctly different types of firestopping: a) through penetration; b) membrane penetration.

    An example of a through penetration in a firewall is a pipe or a conduit running "through" a wall, going in one side of the wall and coming out the other side of the wall.

    An example of a membrane penetration in a firewall is an electrical box for a receptacle out switch, a hole was cut in one side of the firewall (that side is one "membrane" of the firewall) and then a box is installed in that opening. There is no penetration through the membrane on the other side of the wall, i.e., the penetration does not go "through" the firewall.

    Not sure if I complicated this or made it easier? Let me know.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  24. #24
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Marc M View Post
    Or these...
    The metal plate in the first photo is a "firestop". It only does any good if the walls below it are covered and not left as open studs, and I can see quite a few potential problem areas on that exterior framed wall, and maybe on the left interior framed wall.

    That gas line going down into the top plate would need to have been sealed around (firestopping) with proper sealant.

    Jerry Peck
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    Default Re: Ducts entering into the attic...

    Just wanted to add this too: Fireblocking is always done at the lower ceiling level where two ceilings of different heights meet at a common wall. Below the lower ceiling the wall is concealed space and needs to be fireblocked at the ceiling level. Above the lower ceiling the wall space is open to the attic (presuming we are referring either a one story house or the top floor of a multi-story house).

    Jerry Peck
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    Default Re: Ducts entering into the attic...

    I'm not confused at all, that was perfect, thanks again.


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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Jerry Peck View Post
    Just wanted to add this too: Fireblocking is always done at the lower ceiling level where two ceilings of different heights meet at a common wall. Below the lower ceiling the wall is concealed space and needs to be fireblocked at the ceiling level. Above the lower ceiling the wall space is open to the attic (presuming we are referring either a one story house or the top floor of a multi-story house).
    Jerry,

    Very good, and I'm in complete agreement. As an AHJ for 25 years, "firebocking" is one area where I find contractors messing up. And it's something that usually can't be seen on a home inspection. During a rough frame inspection, I found one contractor who installed fire caulking in every hole where electrical wires passed from stud bay to stud bay. He wasn't sure why, but he blamed another AHJ, who told him it was required. I then noticed that he neglected to install blocking at a kitchen soffit. Similar to your scenario of the ceilings with different elevations, blocking where the horizontal portion of a soffit meets the wall is often missed. I always axplain to the contractor that if a fire can spread, concealed, from a wall to a ceiling, it has to be blocked.

    Another area they always miss is in finished basements. The furred-out walls make a great path for fire to get from the wall into the ceiling. If any home inspectors are checking finished basements, and there is an opportunaity to check for blocking in this area (by lifting a suspended ceiling tile, for example), you would be doing your clients a service.


  28. #28
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    Default Re: Ducts entering into the attic...

    We, an AHJ, always require fireblocking in the situations in the pictures. Interesting note on the photo of the fireplace flue, I noticed the metal firestop hanging out there just waiting for someone to seal around the flue.

    On the gas line in the picture.....is the gas line to the right melted?


  29. #29
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    Default Re: Ducts entering into the attic...

    I think the issue of the fire blocking has been answered.
    But (except for a couple of postings) I think too little concern was made about the exposed kraft faced fiberglass batts. I have seen this missed by building inspectors all of the time. IMO that wall is exposed Napalm...just waiting for an electric short or a (the) plugged, hot dryer vent to set off a nice attic fire.

    Several years ago there was a fire at a newer, one story, commercial building here. It had exposed Kraft Faced batts installed about 4 inches above a dropped acoustical tile ceiling. A fire was started by arson in one corner office. As I remember it they got a fire alarm from that business. and while responding they got alarms from the remaining three businesses...one after another about 1 minute apart.

    When we purchased our home about 10 years ago I had to go under our house and turn the insulation paper side up. Many times homeowners or even untrained insulation workers will have the paper side down so they they can staple the flanges....Our home inspector missed this problem even though he made note of the R-11 (printed on the paper) faced batts installed.

    If you see this call it out! With all the Save Energy craze going on you will see this more and more...I betcha'


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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Wayne Carlisle View Post
    We, an AHJ, always require fireblocking in the situations in the pictures. Interesting note on the photo of the fireplace flue, I noticed the metal firestop hanging out there just waiting for someone to seal around the flue.

    On the gas line in the picture.....is the gas line to the right melted?
    No, it wasnt melted. There were so many other issues with that installation though. Did you see the extension cord running into the chase or the vent in direct contact with the framing, non approved firestop...oh, BTW, not to mention that the vent terminated into the attic space!

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    Default Re: Ducts entering into the attic...

    Here's another from a brand new house... Lawsuit waiting to happen..

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    Default Re: Ducts entering into the attic...

    What is wrong then???? Looks melted.




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    Default Re: Ducts entering into the attic...

    It was cut up the middle then ripped or torn.
    Quote Originally Posted by Wayne Carlisle View Post
    What is wrong then???? Looks melted.




  34. #34
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Wayne Carlisle View Post
    What is wrong then???? Looks melted.

    For one thing, the CSST on the left looks bent too sharply, but that could just be an optical illusion (yes, I know this is not what you were referring to).

    Jerry Peck
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Jerry Peck View Post
    For one thing, the CSST on the left looks bent too sharply, but that could just be an optical illusion (yes, I know this is not what you were referring to).

    That looks to ME to be a PRE-MANUFACTURED GAS APPLIANCE CONNECTOR corrugated not site installed CSST. Still crimped, too shallow radius of a bend, especially near fitting, and obviously not protected from DAMAGE; and apparently pulled taught - thus defeating the intent and requirement in the Calif. Codes for the flexible connection (seismic) in the first place.


  36. #36
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by H.G. Watson, Sr. View Post
    That looks to ME to be a PRE-MANUFACTURED GAS APPLIANCE CONNECTOR corrugated not site installed CSST.

    That was my first thought too, then I said "Nah ... can't be, not up there for that use (unless it goes FROM the gas line TO something off to the left and instead of TO the gas line TO the fireplace)."

    Maybe it is a gas connector and maybe it does go to another appliance???

    Jerry Peck
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  37. #37
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    Default Re: Ducts entering into the attic...

    Quote Originally Posted by Jerry Peck View Post
    That was my first thought too, then I said "Nah ... can't be, not up there for that use (unless it goes FROM the gas line TO something off to the left and instead of TO the gas line TO the fireplace)."

    Maybe it is a gas connector and maybe it does go to another appliance???
    Yes its a gas appliance connector. Gas pipe riser, elbow, horizontal to appliance connector. Hate to see proximity to plate and no shut off valve. Probably to the heats for the air handler/furnace (LIKE the original attic he first asked about had to the left of first pic, Hmmm), could also be water heater. So. Calf few heat need days far more AC days. Sleepin' cool air under blankets, more likely to run F/P when awake.


  38. #38
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    Default Re: Ducts entering into the attic...

    For the folks on the West Coast. This is from the CRC; California Residential Code 2010, which becomes effective Jan. 1, 2011.

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    Jerry McCarthy
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    Default Re: Ducts entering into the attic...

    Here are 4 more classics:

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