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  1. #1
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    Default New type of dryer vent?

    I found this today on a new home inspection. I have not come across this type of dryer vent. It is oblong in shape, but truth be known it looks like they just forced a section of round vent pipe into the holder.

    Anyone seen this before?

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    Default Re: New type of dryer vent?

    Bet you're right.

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  3. #3
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    Default Re: New type of dryer vent?

    Only way to get the round vent pipe to fit in the 2x4 stud wall.


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    Default Re: New type of dryer vent?


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    Default Re: New type of dryer vent?

    from last week

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    Default Re: New type of dryer vent?

    Scott,

    As shown in the link Bruce posted, some have an "ovalized" port. However, I don't recall having seen a dryer installation instructions saying that an oval duct is allowed, I only remember seeing 4" diameter, meaning 4" round.

    Bruce,

    I remember previous discussions regarding the use of PVC pipe for dryer vents and I remember we all came to the conclusion that 'other than metal' is not allowed.

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    Exclamation Re: New type of dryer vent?

    When a round cylinder is ovalized, the flow capacity is reduced. Fill a paper cup to the brim with water (not hot coffee, unless you're standing in McDonalds). Now, squeeze the cup. It spills over, right? Now, continue until the effective opening is like a mail slot. Now, you can see where there is very little effective flue area left.
    In order to ovalize any duct, you must start with a larger diameter then squeeze it down. With most mechanical systems, the increase in static pressure is simply overcome by brute force of air pressure. However, in a vent subject to build up such as a chimney or dryer vent, the actual flue capacity can reduce with each layer. The flow capacity of any conduit increases to the cube-not square function as diameter doubles. In other words, a little restriction in diameter has a significant impact on flow.
    HTH,
    Bob

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  8. #8
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    Default Re: New type of dryer vent?

    Did you parents actually give you that name?


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    Default Re: New type of dryer vent?

    .
    Your Video Shows an unlisted, unapproved ( plastic slinky ) abet straight Dryer vent.
    .

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  12. #12
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Billy Stephens View Post
    .
    Your Video Shows an unlisted, unapproved ( plastic slinky ) abet straight Dryer vent.
    .
    Flexible semi-rigid pipe is approved as an appliance connector. Not sure which video you are referring too.

    http://doitbest.com/Dryer+vents+and+...sku-273562.dib


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    Default Re: New type of dryer vent?

    This One.
    Quote Originally Posted by Mr. Dryer Vent View Post
    Not sure which video you are referring too.
    .
    Showing this Mylar Tubing Going straight into your Contraption.
    .



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    Default Re: New type of dryer vent?

    Quote Originally Posted by Mr. Dryer Vent View Post
    Flexible semi-rigid pipe is approved as an appliance connector. Not sure which video you are referring too.

    http://doitbest.com/Dryer+vents+and+...sku-273562.dib
    Well, I just have to ask! Who has approved it?

    The IRC has not approved it and I have never see it listed by any of the dryer manufacturers.

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  15. #15
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Scott Patterson View Post
    Well, I just have to ask! Who has approved it?

    The IRC has not approved it and I have never see it listed by any of the dryer manufacturers.
    Semi-rigid aluminum transition hose is an approved connector when in compliance with IRC (2006) M1502.4 (transition hose).


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    Default Re: New type of dryer vent?

    Billy,

    From what I see in the video, it states that "historically" ... then shows that foil dryer connector slinky, and shows one of the problems with them. These (both foil and plastic) are not approved for use.

    Then, when the video is showing the DryerBox, it shows the flexible metal dryer connector. These (the flexible aluminum types) are approved for use.

    By using a DryerBox and the flexible aluminum dryer connector, the "historical" problems are solved.

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    Default Re: New type of dryer vent?

    Quote Originally Posted by Jerry Peck View Post
    Billy,

    From what I see in the video, it states that "historically" ... then shows that foil dryer connector slinky, and shows one of the problems with them. These (both foil and plastic) are not approved for use.

    Then, when the video is showing the DryerBox, it shows the flexible metal dryer connector. These (the flexible aluminum types) are approved for use.

    By using a DryerBox and the flexible aluminum dryer connector, the "historical" problems are solved.
    .
    Video starts with restricted ( curled ) then shows * attached files
    .

    Attached Files Attached Files
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    Default Re: New type of dryer vent?

    Billy,

    I saw the one in the right photo in the video, but not the one in the center photo.

    You are correct about the one in the center photo, that is the foil one I stated "These (both foil and plastic) are not approved for use.".

    I looked at the two video links again (same video) and I still don't see that in there.

    Nonetheless, with that shown in the video (or any other information they produce) and which shows the foil or plastic type as 'do it this way', that causes the product to lose credibility.

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    Default Re: New type of dryer vent?

    .
    Mr. Peck,
    click (Enter The Site) Slide Show has Mylar tubing being used as dryer venting connect to his product.

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Billy Stephens View Post
    .
    Mr. Peck,
    click (Enter The Site) Slide Show has Mylar tubing being used as dryer venting connect to his product.

    Now I see ... the blind man says.

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    Default Re: New type of dryer vent?

    Quote Originally Posted by Jerry Peck View Post
    Now I see ... the blind man says.
    .
    I Really like The Verbiage " Safe, Effective". after the Mylar tubing fades from view.
    .
    Do you think the Fire Investigator findings would echo his advertisement?

    Oops it says " Efficient" not effective. Wouldn't want to miss represent.

    Last edited by Billy Stephens; 08-24-2008 at 07:07 PM. Reason: oops added
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post
    When a round cylinder is ovalized, the flow capacity is reduced.

    Bob,

    Does that mean that Ovaltine was not really all it was talked up to be?

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    Cool Re: New type of dryer vent?

    Flexible transition ducts must be listed and labeled to UL 2158A, not exceed 8ft, not be concealed within the walls, must be a single piece (no splicing) and approved by the appliance mfr..
    This listing covers issues such as surface burning, flame resistance, bending, corrosion, puncture, impact, tension, and torsion resistance. Most listed ducts such as Thermaflex, GLV, Lambro498P and Petra FO405B are made up of multiple layers of aluminum foil over a wire helix. You can feel the difference btw these and mylar slinkies.

    It is interesting that Mr. Dryer Vent's own site gives a side by side comparison of slinkies noting they have a reduced flow capacity, have been known to not contain lint fires and are not approved by many if not most mfrs. Their site also has a video demonstrating how to attach a semi-rigid aluminum duct, which is mfd. similar to chimney liner. They instruct you to flatten the ridges of the flex with a smooth pipe to enlarge the ID then snip it with scissors so it will slip over the male end of the downstream pipe. There are problems with this technique. Rolling the duct destroys the ridges thus defeating the listing as this portion of the liner can unwind even with a hose clamp attached. Attaching flex to a male end downstream is a collection point for lint and a source of flow restriction. If the mfr. had a factory installed downstream transition to rigid duct that afforded a positive connection with little turbulence and did not create a lip to catch lint, I would be all for it. Otherwise, I'm still a big fan of all rigid duct. Properly installed it really is not that hard to pull the dryer.

    One problem with this dryer vent box is it reduces the R-value of the wall. Technically, you would need permission from the AHJ to install it on an exterior wall in new construction or remodeling.

    Another problem is, this box guarantees flow restriction because it forces you to use ells and offsets. Straight out the back is still the best approach. This box is for those too lazy to figure out where to put the wall penetration.

    If they are so worried about pulling the dryer and accessing this connection, get the dryer mfrs. to put the damn vent connection behind the dashboard instead of the floor! ;-)

    While this product seems to reduce the incidence of crushed slinkies, I still feel the best approach is proper layout and installation of rigid so you don't have to worry about crushed/ blocked hoses. BTW, duct obstructions can raise internal temps. inside the dryer dramatically because this is also the cooling system for the dryer.

    I've seen many a foil slinky torn to pieces by rotary dryer vent cleaning apparatus. I've also seen them pinch where they were slung overhead by a string or wire. Just a poor product choice IMHO.

    Keep the fire in the fireplace.

  24. #24
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post

    It is interesting that Mr. Dryer Vent's own site gives a side by side comparison of slinkies noting they have a reduced flow capacity, have been known to not contain lint fires and are not approved by many if not most mfrs. Their site also has a video demonstrating how to attach a semi-rigid aluminum duct, which is mfd. similar to chimney liner.....
    Where does the comparison that you reference appear on "our" website?

    Last edited by Mr. Dryer Vent; 08-28-2008 at 09:29 AM. Reason: corrected information.

  25. #25
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post
    Another problem is, this box guarantees flow restriction because it forces you to use ells and offsets. Straight out the back is still the best approach. This box is for those too lazy to figure out where to put the wall penetration.

    Bob,

    Have you ever seen a dryer vented straight out the back and through the wall with *NO* bend?

    Our old house in South Florida was set up that way ... except that the dryer outlet did not align with the vent through the wall, so I had to offset it 8", which means two 90 degree bends.

    Our house up here in Ormond Beach is also set up that way, except that it too does not align with the dryer outlet, so I had to offset it 12", meaning two 90 degree bends.

    Granted, I did NOT do it the easy way, I used galvanized duct sections cut to length and two galvanized 90 degree elbows.

    Nonetheless, *in most installations I have seen* the DryerBox does, or would if installed, eliminate at least one 90 degree bend, or, in cases like mine - two 90 degree bends, that effectively saves 10 feet of dryer vent length right there.

    The other thing it does, and this is probably even more important than the above, is it eliminates the need to crush the dryer connector back to the wall, the dryer duct sticking out of the wall, and the back of the dryer. When doing that with flexible metal (aluminum) duct, that stuff crushes right up and is toast almost immediately. Don't even start me on the foil or plastic dryer connectors ... .

    I am a believer and a proponent of the DryerBox ... when installed properly in the proper location ... as it save crushing the dryer connector between the dryer and the wall.

    That is not to say that I accept "ovalized" duct ports - my reasons where the same reasons you pointed out - the opening is now "too small".

    If you can fit a 4" dryer vent in the wall stud cavity, you can fit a DryerBox in there with the round opening. This is because a 4" dryer vent will not fit in a 2x4 stud wall, it needs to either be a 2x6 stud wall or be furred out - and either one will accommodate the DryerBox.

    And, yes, in an exterior wall that does eliminate the required R-value at that location, so just design the house (this is, after all, being installed at "new construction" or "remodeling") so it is in an interior wall.

    Of course, how do you install 3" DWV pipes in exterior walls? Not only do they reduce the R-value more than the DryerBox does, but that leaves the piping *outside the thermal envelope* which means that the piping must now be insulated (above the freeze line which basically goes from Jacksonville, FL, through Tallahassee, Fl, through Pensacola, FL, though southern TX, and out through southern CA in an arcing line.

    So, any builder with smart "designs around having piping in exterior walls". The DryerBox is no different.

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    Default Re: New type of dryer vent?

    Quote Originally Posted by Mr. Dryer Vent View Post
    Installations by our company comply with the CSIA standard which meets or exceeds building codes & manufacturer's recommendations.
    Does your website show those foil and/or plastic slinky dryer connectors as being acceptable (i.e., do you show them being used without saying not to use them)?

    Yes or no question.

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  27. #27
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Jerry Peck View Post
    Does your website show those foil and/or plastic slinky dryer connectors as being acceptable (i.e., do you show them being used without saying not to use them)?

    Yes or no question.
    Our website displays vinyl / foil connections as problematic resulting in obstructions to the venting system or laundry dryer. The need for repair results in replacement of vinyl hose type connections with rigid 26 gauge vent piping.


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    Question Re: New type of dryer vent?

    "Installations by our company comply with the CSIA standard which meets or exceeds building codes & manufacturer's recommendations."

    What standard is this? Are you referring to the Certified Dryer Exhaust Technician program? That is a training program--not a std.

    Keep the fire in the fireplace.

  29. #29
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Jerry Peck View Post
    Does your website show those foil and/or plastic slinky dryer connectors as being acceptable (i.e., do you show them being used without saying not to use them)?

    Yes or no question.
    Quote Originally Posted by Mr. Dryer Vent View Post
    Our website displays vinyl / foil connections as problematic resulting in obstructions to the venting system or laundry dryer. The need for repair results in replacement of vinyl hose type connections with rigid 26 gauge vent piping.
    Is that a 'Yes.' or a 'No.'?

    Me: "(i.e., do you show them being used without saying not to use them)?"

    You: "vinyl / foil connections as problematic"

    But ... *do you state (as I asked) "not to use them"*?

    While I certainly admit that I have not read *all* clothes dryer manufacturer installation instructions, I can absolutely state that I have not yet read even *one* which allows those foil/plastic dryer connectors to be used. Every single manufacturer installation instructions I have read has a big *WARNING* box and specifically states *DO NOT USE* those, to *ONLY USE* rigid metal or (when, and only when, rigid metal cannot be used - I have forgotten their exact wording, but they want rigid metal used) flexible metal dryer vent connectors.

    If you are the professionals you state you are, you should be *CLEARLY WARNING ABOUT THE USE* of those foil/plastic dryer connectors and clearly stating *DO NOT USE THEM*. I.e., lose the "problematic" and state "do not use".

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  30. #30
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    Default Re: New type of dryer vent?

    Why not just vent it straight into the crawl space thru a white vinyl hose?

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  31. #31
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    Default Re: New type of dryer vent?

    I noticed that the UL listing for both A and B assemblies required a 2x6 stud size, 2x4 stud size was not listed indicating that the installation method using a normal 2x4 wall (as is used in the original photo requiring an oval shape) is not not an approved method. Am I missing something?


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    Exclamation Re: New type of dryer vent?

    I don't want to sound too much like I'm bashing this box because I do see it has merit and does mitigate some of the problems with dryer venting. However, since a representative of this company has joined this discussion touting their company as a resource for dryer venting, I feel I should point out a few discrepencies.

    The IRC 1502.4 clearly states flexible transition ducts must be labeled and listed (UL 2158A). Yet, this same company sells unlisted ducts on their website!
    Again, in IRC 1502.5, rigid duct must be a minimum of 0.016 inch thickness, which equates to heavier than 27 gauge( which is 0.0164"). That means 26 ga. number or lower ( higher the number, the thinner the guage). Why then do they sell 30 ga. duct on their website?

    In their defense, they do make a broad radius 90 degree ell. I don't like that it comes in two pieces but it may be better than 26 ga. galvanized 90 degree adjustable ells with their joints.

    Back to IRC 1502.5- all joints must be in the direction of flow. That means attaching a slinkie onto another piece of rigid where the male end of the rigid enters the slinkie pointing upstream, is prohibited by code. They sell a short transition duct with a factory transition but the flex is not listed hence not allowed. Get it listed with a male downstream connection and I think they are on to something.

    FYI, here is the link I referred to about additional info. from this site: Dryer Venting Guidelines - How to avoid dryer fire hazards

    still waiting on those CSIA Stds.....
    Bob

    Last edited by Bob Harper; 08-25-2008 at 09:05 AM.
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    Default Re: New type of dryer vent?

    Bob,

    There is a conflict between the codes as regards to residential clothes dryer duct construction requirements.

    The IRC allows for 0.016, which is 28 gage. The IMC allows for 0.013, which is 30 gage.

    One would think that a clothes dryer in a dwelling unit (single family house) would be, if anything, less restrictive than for a clothes dryer in a dwelling unit (apartment/condo/etc.) - not more restrictive.

    In fact, the IMC does not address (specifically) the thickness of the metal used for domestic clothes dryer ducts which do not penetrate fireblocking or into fire resistive assemblies.

    - From the 2006 IMC. (underlining is mine)
    - - 504.6 Domestic clothes dryer ducts. Exhaust ducts for domestic clothes dryers shall be constructed of metal and shall have a smooth interior finish. The exhaust duct shall be a minimum nominal size of 4 inches (102 mm) in diameter. The entire exhaust system shall be supported and secured in place. The male end of the duct at overlapped duct joints shall extend in the direction of airflow. Clothes dryer transition ducts used to connect the appliance to the exhaust duct system shall be limited to single lengths not to exceed 8 feet (2438 mm) and shall be listed and labeled for the application. Transition ducts shall not be concealed within construction.

    However, if they penetrate fireblocking or fire rated assemblies, then:

    - (underlining is mine)
    - - 504.2 Exhaust penetrations. Ducts that exhaust clothes dryers shall not penetrate or be located within any fireblocking, draftstopping or any wall, floor/ceiling or other assembly required by the International Building Code to be fire-resistance rated, unless such duct is constructed of galvanized steel or aluminum of the thickness specified in Section 603.4 and the fire-resistance rating is maintained in accordance with the International Building Code. Fire dampers, combination fire/smoke dampers and any similar devices that will obstruct the exhaust flow, shall be prohibited in clothes dryer exhaust ducts.

    - (underlining is mine)
    - - 603.4 Metallic ducts.All metallic ducts shall be constructed as specified in the SMACNA HVAC Duct Construction Standards—Metal and Flexible.
    - - - Exception: Ducts installed within single dwelling units shall have a minimum thickness as specified in Table 603.4.
    - - - TABLE 603.4
    - - - - DUCT CONSTRUCTION MINIMUM SHEET METAL THICKNESSES FOR SINGLE DWELLING UNITS
    - - - - - DUCT SIZE - | - - - GALVANIZED - - - - - | - - APPROXIMATE ALUMINUM B&S GAGE
    - - Round ducts and - | Minimum --| - Equivalent - | - - 26
    enclosed rectangular - | thickness -| - galvanized - | - - 24
    - - - - - - - - ducts -- | (inches) --| - gage no. - - |
    - - - - - - 14" or less - | 0.013 ----| - 30 - - - - - |
    - - - - - - - Over 14" - | 0.016 ----| - 28 - - - - - - |

    Be that as it may, 30 gage clothes dryer ducts ARE allowed to be installed and used in dwelling units.

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    Cool Re: New type of dryer vent?

    Jerry, I'm just going by the IRC M1502.5 Duct Construction- "Exhaust ducts shall be constructed of minimum 0.016 inch (0.4mm) rigid metal ducts having smooth interior surfaces with joints running in the direction of air flow. Exhaust ducts shall not be connected with sheetmetal screws or fastening means which extend into the duct"

    That seems pretty clear to me that if the IRC applies in your area, then your ducts must be min. 26 gauge. I don't know where you are getting 28 gauge for 0.016--I guess our references don't agree.

    Yes, there is confusion when you must refer to the IMC and rated assemblies requiring firestopping. However, for your typical unrated residential application, it seems to me the IRC M1502.4 is clear.

    In general, 30ga. is allowable only for warm air ducts. In practice, if you get a lint fire, the heat will distort the duct to the point it tears the lockseam open. Even if the IMC has a loop hole, why woud a pro sell a beer can thickness duct?

    I agree w/ your point about clarification by this provider that cheap slinkies are not approved. Too wishy-washy. I would have thought they would be extolling the evils of cheap unlisted duct then selling their own listed duct, once they spend the money to get it listed.

    BTW, you can use rigid duct from any mfr. and it does not have to be listed. They can, however, pay a recognized testing lab to test their rigid to the applicable portions of the UL listing and provide that test report. You won't be able to list the rigid under that std. because it deals with flexible ducts but the fire resistive portions along with the tension, compression, and torsion may apply. It would be a marketing tool for sure.

    FYI, Lindaub used to make seamless stainless steel duct with broad radius ells. Great duct but hard to find and expensive.
    Bob

    Keep the fire in the fireplace.

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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post
    Jerry, I'm just going by the IRC M1502.5 Duct Construction- "Exhaust ducts shall be constructed of minimum 0.016 inch (0.4 mm) rigid metal ducts having smooth interior surfaces with joints running in the direction of air flow. Exhaust ducts shall not be connected with sheet metal screws or fastening means which extend into the duct"

    That seems pretty clear to me that if the IRC applies in your area, then your ducts must be min. 26 gauge. I don't know where you are getting 28 gauge for 0.016--I guess our references don't agree.

    Yes, there is confusion when you must refer to the IMC and rated assemblies requiring firestopping. However, for your typical unrated residential application, it seems to me the IRC M1502.4 is clear.
    Bob,

    First, the IRC *only applies to* one and two-family dwellings and townhouses, it does not apply to all "dwelling units", which is why I was pointing out that another, and different, code exists and applies to "dwelling units'.

    And that there was a conflict between the two ICC codes, with the code which one would expect to be more stringent (IMC) was actually less stringent - go figure that one out????

    The reference I posted regarding gage thickness was right out of the IMC.

    I did a Google search and found this ( Theoretical gauge thickness ) as being one of the best gage tables.

    - allows 27 gage (0.0164) but not 28 gage (0.0149) to fall at 0.016 or thicker
    - allows 29 gage (0.0135) but not 30 gage (0.0120) to fall at 0.013 or thicker

    The IMC picks it up 28 gage for 0.016 and 30 gage for 0.013 - don't ask me why, it just does.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  36. #36
    Todd Peach's Avatar
    Todd Peach Guest

    Default Re: New type of dryer vent?

    First of all, thanks guys for the heated and thorough discussion. We have a Google search that alerted me to this thread, and I really enjoyed reading your ideas about the importance of properly venting the dryer.

    For introductions, my name is Todd and I do head up marketing at the Dryerbox. This forum looks to be a very useful tool, so I'll try and minimize my biased praise of our products.

    For the record, we have not yet contributed to this discussion:

    Quote Originally Posted by Bob Harper View Post
    . . . since a representative of this company has joined this discussion touting their company as a resource for dryer venting, I feel I should point out a few discrepencies . . .
    But we do appreciate the kind words about the Dryerbox from others who have already joined this thread.

    I'll start with a confession: at Dryerbox - Safely Vent Your Dryer - dryer vent pipe, dryer vent hose, dryer vents, dryer venting, dryer lint, dryer vent kit, dryer vent box we do have a few very old images showing foil flex versus the semi-rigid hose we do recommend. We will work to start replacing the old images.

    We do agree that semi-rigid flex should be used to terminate the dryer's exhaust. We also recommend that a 2 X 6 wall better supports all of the trades that usually need to be in the laundry room wall (models 425 and 4D are built with round holes and fit in 2 X 6 walls). These models account for 90% of all Dryerboxes installed (1.6 million plus). We do make models available that have a slightly "ovalized" hole for projects that don't have enough room in the wall or to allow for extra insulation behind the receptacle.

    An important note: the image that started this thread is not of an original Dryerbox, but a plastic imitator. Knowing that over 40 dryers burst into flames every day, we can not stress enough that plastic should not be used behind the dryer.

    Properly venting the dryer is, as you have all pointed out in this discussion, very important. Please do feel free to contact us at 888-443-7937 with any questions on installing the Dryerbox.

    And, thanks again to all. Keep up the great work.

    Last edited by Todd Peach; 08-26-2008 at 08:17 AM. Reason: typo

  37. #37
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    Default Re: New type of dryer vent?

    Todd,

    Welcome to THE inspectors forum.

    Also thank you for replacing (beginning to replace) those "unsafe and not allowed to be used slinky type" dryer connector images.

    Are your dryer boxes fire rated, i.e., are they rated for installation in a 1 hour fire rate wall assembly?

    If so, do you have any specifications on what needs to be done when installed in such a wall?

    Thank you.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  38. #38
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Todd Peach View Post
    --we do have a few very old images showing foil flex versus the semi-rigid hose we do recommend. We will work to start replacing the old images.
    .
    Yep! ( Makes it Harder to convince People of the Fire Hazard! )

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  39. #39
    Todd Peach's Avatar
    Todd Peach Guest

    Default Re: New type of dryer vent?

    Quote Originally Posted by Jerry Peck View Post
    Are your dryer boxes fire rated, i.e., are they rated for installation in a 1 hour fire rate wall assembly?

    If so, do you have any specifications on what needs to be done when installed in such a wall?
    Yes. All four new construction models have been classified by UL and rated for 1 Hour F and T. You may find the UL information at:

    The Dryerbox is UL Approved for a One Hour Wall

    Additional specifications can be found at:

    Specifications -- Select the Right dryer boxes for Your Application


  40. #40
    Mr. Dryer Vent's Avatar
    Mr. Dryer Vent Guest

    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post

    ....It is interesting that Mr. Dryer Vent's own site gives a side by side comparison of slinkies noting they have a reduced flow capacity, have been known to not contain lint fires and are not approved by many if not most mfrs. Their site also has a video demonstrating how to attach a semi-rigid aluminum duct, which is mfd. similar to chimney liner. They instruct you to flatten the ridges of the flex with a smooth pipe to enlarge the ID then snip it with scissors so it will slip over the male end of the downstream pipe....
    Todd,

    I did not understand Bob's post but now understand the confusion.

    It appears that some individuals confused my post referencing the "Dryerbox" product as being a product of my own. "Mr. Dryer Vent" is a residential & commercial vent cleaning company. While we have used the "Dryerbox" product in repairs and installations, we have no other relationship with the company.


  41. #41
    Todd Peach's Avatar
    Todd Peach Guest

    Default Re: New type of dryer vent?

    Thanks, Mr. Dryer Vent, for installing the Dryerbox and for the clarification. We're pleased you've found it useful for some of your customers. I should also point out that I found Bob's posts very helpful and really appreciate everyone's input.


  42. #42
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Mr. Dryer Vent View Post
    Todd,

    1. I did not understand Bob's post ---

    2. we have no other relationship with the company.
    .
    1. Yeah ? ( or you do you not want to answer his Questions ? )
    .
    2. ( below )

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  43. #43
    Mr. Dryer Vent's Avatar
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Billy Stephens View Post
    .
    1. Yeah ? ( or you do you not want to answer his Questions ? )
    .
    2. ( below )
    Bob's questions with regard to photos do not appear on my website. What question in your mind remains unanswered....?


  44. #44
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post
    "Installations by our company comply with the CSIA standard which meets or exceeds building codes & manufacturer's recommendations."

    What standard is this? Are you referring to the Certified Dryer Exhaust Technician program? That is a training program--not a std.
    Quote Originally Posted by Bob Harper View Post
    I don't want to sound too much like I'm bashing this box because I do see it has merit and does mitigate some of the problems with dryer venting. However, since a representative of this company has joined this discussion touting their company as a resource for dryer venting, I feel I should point out a few discrepencies.

    The IRC 1502.4 clearly states flexible transition ducts must be labeled and listed (UL 2158A). Yet, this same company sells unlisted ducts on their website!
    Again, in IRC 1502.5, rigid duct must be a minimum of 0.016 inch thickness, which equates to heavier than 27 gauge( which is 0.0164"). That means 26 ga. number or lower ( higher the number, the thinner the guage). Why then do they sell 30 ga. duct on their website?

    In their defense, they do make a broad radius 90 degree ell. I don't like that it comes in two pieces but it may be better than 26 ga. galvanized 90 degree adjustable ells with their joints.

    Back to IRC 1502.5- all joints must be in the direction of flow. That means attaching a slinkie onto another piece of rigid where the male end of the rigid enters the slinkie pointing upstream, is prohibited by code. They sell a short transition duct with a factory transition but the flex is not listed hence not allowed. Get it listed with a male downstream connection and I think they are on to something.

    FYI, here is the link I referred to about additional info. from this site: Dryer Venting Guidelines - How to avoid dryer fire hazards

    still waiting on those CSIA Stds.....
    Bob
    Quote Originally Posted by Mr. Dryer Vent View Post
    Bob's questions with regard to photos do not appear on my website. What question in your mind remains unanswered....?
    .
    Some of these .
    .

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  45. #45
    Mr. Dryer Vent's Avatar
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    Default Re: New type of dryer vent?

    Billy,

    Bob's questions refer to situations that do not appear on our website.

    As a Vent Cleaning / Repair Company, our recommendations to be followed resultant of our inspection of the vent system is at the discretion of the Building Owner. Their choice to make repairs recommended is their own.


  46. #46
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Mr. Dryer Vent View Post

    Installations by our company comply with the CSIA standar
    d which meets or exceeds building codes & manufacturer's recommendations.
    Quote Originally Posted by Bob Harper View Post
    "Installations by our company comply with the CSIA standard which meets or exceeds building codes & manufacturer's recommendations."

    What standard is this? Are you referring to the Certified Dryer Exhaust Technician program? That is a training program--not a std.
    Quote Originally Posted by Mr. Dryer Vent View Post
    Billy,

    Bob's questions refer to situations that do not appear on our website.


    .
    .
    This is a Question about your Statement.
    "Mr. Dryer Vent."
    .

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  47. #47
    Mr. Dryer Vent's Avatar
    Mr. Dryer Vent Guest

    Default Re: New type of dryer vent?

    Billy,

    Compliance with the CSIA (C-DET) Standard will exceed most Municipal & IRC Standards.

    Do you disagree?


  48. #48
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Bob Harper View Post
    "Installations by our company comply with the CSIA standard which meets or exceeds building codes & manufacturer's recommendations."

    What standard is this? Are you referring to the Certified Dryer Exhaust Technician program? That is a training program--not a std.
    Quote Originally Posted by Mr. Dryer Vent View Post
    Billy,

    Compliance with the CSIA (C-DET) Standard will exceed most Municipal & IRC Standards.

    Do you disagree?
    .
    I disagree that it is a Standard.

    Mr. Harper's point ( I think ) was you referencing a Standard which is not a Standard but in fact a Training Program.
    Earning the CSIA C-DET Credential
    .

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  49. #49
    Mr. Dryer Vent's Avatar
    Mr. Dryer Vent Guest

    Default Re: New type of dryer vent?

    The C-Det is a testing and certification program. C-Det references building codes that are applicable. You are correct that C-det is not a standard of its own.


  50. #50
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    Cool Re: New type of dryer vent?

    MR Dryer, thanks for clarifying that point for me. It may sound trivial but it is not.

    CDET means you got at least 40 out of 50 questions correct on an exam. There is no training or mandatory education required. While there is a bit about codes in the exam, there is also much about sweeping techniques and cleaning the dryer itself. FYI, I sat in on the very first CDET course ever offered.

    I saw a picture on a website of someone installing one of those plastic soffit vent terminations for a dryer vent. These have plastic louvers, which can catch lint. I think this meets the definition/ intent of a "screen" in IRC M1502.2, which prohibits screens.

    I hope this discussion has not offended anyone but I think it has been very educational for us all, including me.

    Keep the fire in the fireplace.

  51. #51
    Gary Smith's Avatar
    Gary Smith Guest

    Default Re: New type of dryer vent?

    Using claims that a particular product or service has met a certain "standard" is fairly dangerous and even a half-ass, beginner model attorney will be able to uncover the mask of "see our product/service is safe because installers have taken one of our tests" ... I think the Federal Trade Commission has a few rules about false advertising.


  52. #52
    Ron Bibler's Avatar
    Ron Bibler Guest

    Default Re: New type of dryer vent?

    Hey Scott. Inspected a new home today in the back of the laundry room was a metal box with a dryer vent that was oblong in shape. 2x4 wall. the box was not set flat or flush with the sheetrock and look like it was install upside down by the info on the back. it had a punch out for the gas but the guy cut a new hole in the side for his gas pipe...

    I will get the web site and photo posted

    Saw this and had to go back and dig up this old post.

    Best

    Ron


  53. #53
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  54. #54
    Jon Bolton's Avatar
    Jon Bolton Guest

    Default Re: New type of dryer vent?

    Gentlemen:

    Any chance of getting a copy of UL 2158A?

    jon@inspectagator.com

    Thanks in advance.


  55. #55
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    Default Re: New type of dryer vent?

    Quote Originally Posted by Ron Bibler View Post
    Hey Scott. Inspected a new home today in the back of the laundry room was a metal box with a dryer vent that was oblong in shape. 2x4 wall. the box was not set flat or flush with the sheetrock and look like it was install upside down by the info on the back. it had a punch out for the gas but the guy cut a new hole in the side for his gas pipe...

    I will get the web site and photo posted

    Saw this and had to go back and dig up this old post.

    Best

    Ron
    I have seen a couple more since I posted this.

    Scott Patterson, ACI
    Spring Hill, TN
    www.traceinspections.com

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