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Who is Dana Dorsett?

bobhol | Posted in General Questions on

I have been an avid follower of GBA and its articles …I have asked questions and received incredibly good advice from a variety of sources including Martin Holladay and Dana Dorsett .Martins credentials and pictures are readily available …but …who is Dana Dorsett .The advice from Dana is greatly appreciated and is very precise and has bona fide additional references…BUT…I need to know who you are…thanks,Bob Holodinsky

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  1. Expert Member
    Dana Dorsett | | #1

    Just some hack, not even in the construction biz, so don't trust any drivel he throws up on these boards!!

    He seems to know a little something about ski racing though: ;-)

    1. jordan_harder | | #29

      This thread cracks me up after having a similar who the hell is Dana Dorsett experience..

      Appreciate your comments and articles on here, and I must say they do make me feel like I need to educate myself massively more on whatever the subject is.

      Dana, do you do heating system design/consulting, or are you open to it?
      Wanting to do radiant heat, and the panel rads are the emitter that I am gravitating towards. Seems like you are incredibly familiar with how these systems work.

  2. bobhol | | #2

    lol.... nice!!!

  3. GBA Editor
    Martin Holladay | | #3

    I appreciate Dana's modesty and sense of humor. But now is as good a time as any to extend my sincere thanks to Dana for his valuable contributions to the GBA forum.

    Thanks, Dana. Keep it up.

  4. Expert Member
    Dana Dorsett | | #4

    Martin- you aren't gonna tell anybody what I paid you to say that, right? :-)

    (You're welcome!)

  5. bobhol | | #5

    I am also very grateful for the information Dana has passed along to me....thank you and keep it up ...I am sure to be asking more questions,regards Bob

  6. LucyF | | #6

    To Dana and Martin,

    We raise a bottle of IPA and say thank you. (I learned about IPA on this forum.) We really appreciate your help and kindly advice.

  7. jinmtvt | | #7

    I was going to say something positive...
    but after watching the video i am unsure of Dana's mental stability ...

    Hey Dana, i know you mentioned it once, but i don't recall it clearly, where are you from again ??

    On a more serious note, i also have to thank you Dana about your input on this forum,
    i have been an avid follower of you and Martin since i started reading on this forum.
    Both you guys complete each other vey well.

    Invaluable participation to this forum/community.
    congrats sifu Dana ! :p

    Maybe a picture of your face would be in order now that you are world reknown for your building intellectuality.

  8. Expert Member
    Dana Dorsett | | #8

    Jin: The silly-slalom clips were taken on 31 May 2013, at the Mt. Wachusett Ski area in central MA, a 30 minute drive from my home. (Some years I will ski that hill more days after closing than I do during the lift-served season. This wasn't one of those years.)

    I was hoping to do it on 1 June with one of my old racing buddies but there was a heat wave in progress, didn't think it was going to make it (it didn't.) Drive-by "silly skiing" events long after the lifts had closed for the season, have become a tradition amongst a handful of my backcountry & ski-racing comrades. The latest I'd ever "skied" it was 6 June 2005, on a patch even smaller than that:

    A few days prior on 1 June 2005 conditions had been a bit "better" on an outing with one of my racing team mates. He skied it on a randonee (backcountry fixed-heel) race setup, I was on steel edged cross country gear- the first skier in this clip:

    More typical late-April post-season runs (about 3-4 weeks after closing) look something like this:

    Skiing (particularly bad skiing :-) ) & ski-racing is one hobby, green building & energy/carbon-policy issues are another. Linquistics might be a distant third I've been picking up a smattering of Hindi watching Bollywood movies on NetFlix this year- just enough to get myself into trouble at this point... I was surprised at the German-like syntax and the large overlap of similar/same sounding common words between Hindustani & western European languages- much more similar than I'd previously thought. This Hindi/Urdu/Punjabi stuff is starting to grow on me- much more accessible than I thought it would be.

    So, that's me.

    As far as pictures go, I'm the guy in the red sweater in the front row on the pic in this article:

    (My friend Jeff whose project this was is the tall guy in the back hiding in the shade. Looks like Hobbit made a cameo there too, front row, far right.)

    I looked but didn't find a clearer/more recent face pic on this machine or the web. Best I can do is this clam-digging shot (@ Copalis,WA) from 8 years ago. (I'm the big kid on the right in the purple windbreaker. ;-) )

  9. jinmtvt | | #9

    You look like a hairy nerd!!! :p

    Nerd in the good way though ...
    ur kid ?

    nice sandals to play in the wet sand ( NOT )

    Why learning hindu ??

    So you are from Mass ... i passed near your place
    visiting family in RI
    and my mom in law lives in Mass also :)
    Are you from there originally ?

    Anyhow, you've got my respect sifu Dana,

    i enjoy reading your replies, alot!
    your thinking goes in a direction i am trying to point at myself ...

  10. Expert Member
    Dana Dorsett | | #10

    Yep- the hairy nerd is me, and that's my kid, although he's a lot bigger now than when that was shot. That was in my home state of WA, visiting relatives at the time. My mother managed to borrow a beach house for the weekend so we went for it. I've lived many places, but MA has been my home continuously since about 1990 (and for much of the 1980s too.)

    I have no reason for learning Hindi, I just can't help it (must be a brain defect :-) ) My wife & sister-in-law (who stayed with us for several months last year) got into watching Hindi movies on NetFlix, and became enamored of the actor Shahrukh Khan. (IMHO he's a pretty good actor with quite a range of roles & talent covering several genres from romantic comedy to action thrillers to horror. He can actually dance too, and can fake some of the martial arts stuff without using a body double.) The regular German-like syntax and the many many similarities in vocabulary with European languages had it sinking in by osmosis during the first Bollywood movie we watched- it seemed WAY too easy.

    The points of similarity aren't with any one European language- there seem to be as many Latin-isms as there are German-isms, but they're steeped deeply into the language. eg: the Hindi word for "what" fits somewhere between the French "qua" and Spanish "que", pronounced "kya". Hindi for "hand" is simply "hand", "one two three" is "ek do teen", the two common words for "yes" are "ha" which rhymes with the germanic "ja", and "ji" , which rhymes with the Italian/Spanish "si". "No" is the same as the Scandinavian/Dutch "nee" or English "nay", "name" is identical with the Dutch "naam", "I" or "me" is pronounced like the Spanish "me", "you" is the same as the Latin "tu", which rhymes with the germanic "du", and the similarities just keep going & going- the vocabulary is rife with it. It's a far more closely related language than I had been aware of - despite knowing it was a "Indo-European" language, I hadn't previously experienced how deep those connections are. (Yes, there really IS a common root lanquage! And how is it that people who look like Nepalis or Bengalis have a common ancestral language with people who look like Saxons or Swedes? There are some fair-featured Punjabis, but not a majority. That proto-tribe of Indo-Europeans just got around a lot, played the field, I s'pose.)

    Hearing it spoken while reading English subtitles the syntax gets garbled. But treating is as a pidgin-German or something and open up your liquistic auditory filters it all starts making sense, or at least sort of... With a smattering of nouns and verbs embedded in the auditory brain the rest starts to come together, including the rules of syntax. The verb "to be " is "hai", (not very similar to any European version that I'm aware of) but as in German the verb goes at the end of the sentence, eg: "My name is Dana." would be "Mera naam Dana hai", literally "My name Dana is." Not a tough syntax to get used to, if a bit odd for English-only speakers. Hindi seems devoid of the complexities of Slavic lanquages, and even streamlined compared to western European languages, but nowhere near as pared down as the elegance of Mandarin or Cantonese. I can't really tell if Hindi Urdu and Punjabi have more than an accent or dialect difference, but to my none-too-familiar ear they seem more alike than different (and distinct from Bengali or Tamil.)

    Another aspect of Bollywood movies is that many educated people in India will flip between English and Hindi regularly in normal conversations, sometimes mid-sentence It's usually pretty clear by context which phrases or words are adopted Anglicisms into Hindi vs. just saying it in English for emphasis or expression or just for the hell of it. Many Indian high schools teach most or all subjects in English, and fluency is high amongst the urban Indian middle class, but not so much in the remote villages, at least as reflected in the movies. I have no fear of English taking over Hindi, just as there's no chance of Hindi overwhelming Tamil or Bengali, etc, but it's commonly heard in the movies.

    Enough with the Hindustani lesson. Bottom line, it's just not all that hard to understand with a bit of exposure. My wife thought I was making it up- Hindi makes no sense to her beyond a few expressions, but I can't watch a Hindi movie without picking up vocabulary. She keeps watching them, and if I'm parked on the chesterfield with her I'm stuck learning it whether I mean to or not, though on some of the really predictable movie plots I'll concentrate on the linguistic aspects just to keep it entertaining. Like a said- it's another hobby that deepens my appreciation of the interconnectedness of human civilization. The cultures of south Asia used to seem somewhat "firang" (Hindi slang for "foreigner", used in a similar manner as "gaijin" in Japanese) to me, but in the past year Hindustani culture has started feeling a bit more "desi" (Hindi meaning something sort of ike "part of us" or "one of ours", akin to urban-US "my homey".). I guess you really CAN export culture via cinema. But just the view of US culture from Hollywood is through a distorting lens, I'm sure Bollywood skews it's subjects just as badly.

    BTW: Kazama is a Japanese family name, "sifu" is Cantonese for (the Mandarin) "shifu", "jin" is Mandarin for "gold" and a common Chinese family name as well as a fairly Japanese & Korean first/second name. Is there an Asian history there, or did you just borrow the handle from the Japanese video game character? (I've never played the game, only seen the character.)

  11. jinmtvt | | #11

    Dana : borrowed from game charachter ...been teaching "n00bs" at Tekken and Virtua Fighter all my teen years ...

    i am of french canadian origins, will probably change my name to real one later on here,
    i just like the anonymat when i am on a new place..but i guess that GBA starts to feel more like a regular site/community to me ..

    How is it that you seem interested in linguistic ?? i find it "abnormal" for an " " " american " " "... :p
    unless you are of other origins ...

    sifu = usually refers to master in gunfu , or father in family

    btw my wife is vietnamese ( my kids are hybrids :p ) , that's probably as far as i go toward
    asianacity :p

    "" still wondering why the interest for hindi and bollywood ""
    how do you even find the time to watch those shitty movies neway ??

  12. badgerboilerMN | | #12

    More proof that a grasp of math is often accompanied by a mastery of languages as well.

    Hell, I wish I could type as fast as Dana. Forget about the physics, mathematics and linguistics. Still my physics hero and one of the few I follow on any blog, anywhere. A nerd every boy wishes to become and every man wishes he was.

    I think he changed his name to protect the ignorant.

    I wish, he were my neighbor, "high-bred": kids and all.

  13. Expert Member
    Dana Dorsett | | #13

    Jin's family probably looks a little bit like one my brother's young grandkids (he has four, all of whom are learning or already speaking Mandarin but only one with grandparents in China.) She has grandparents and great-grandparents from Poland, Lithuania, Israel, China, not just the US.

    My own heritage is 'Merican Mutt from the Pacific Northwest going back several generations. They're mostly western-European types- a few Celts & Angles, some Germans of both swamp & mountain types, but I've never bothered to chase it all down or chart it (a combination of ignorance & apathy.) The town where I went to high school was probably about 10-15% 2nd & 3rd generation Japanese, some of whom had a handle on the language. My other brother married a Japanese citizen- learned a fair amount of Japanese while living with them one summer, when her non-anglophone friends came over for a visit. I've spent some time in Japan, and I've worked in Korea (where I can at least read the menus) and briefly in China (where I can't), as well as the Netherlands (which is much easier for English speakers to learn.) My kid has recent ancestors from central Mexico to central Poland tp central Vermont- he speaks French better than me (he actually studied it), but my Spanish is (for now) better than his.

    I'm hardly a master at any of these- the best I can currently do with any fluency is bad-Dutch (about 3 biertjes into it), but I can also muster bad-Spanish when pressed. Understanding the gist of a conversation or catching phrases here & there isn't exactly the same as mastery. I can read them better than I can speak them- not enough practice, I guess.

    I don't know pho about Vietnamese (other than a collection food or place names. :-) ) While there's a small Vietnamese population in my current home city, there a bigger population of Khmer speaking Cambodians, and an even larger population from west Africans- mostly from Ghana (don't know any Twi myself, but it's offered as a night class in the public schools), and a large contingent of Caribean-Spanish speakers. I can't go to the store without hearing other languages, even I can't tell if it's Serbian or Bulgarian and next door neighbors are Russian-speakers from Belarus. English with a US accent is still the most common language heard, but not by a huge margin.

    There's quite a range of production & script quality in Bollywood movies- they're not all as simple-minded or low budget as they used to be. The average has come up quite a bit in just the past decade, and are not targeted merely at the village grandmothers. Some of the higher-budget action-thrillers are no worse than the same genre coming out of Hollywood, much better scripted & acted than most Hong Kong martial arts films. (eg Farhan Akhtar's "Don" , and "Don-2" have of a "Die Hard" kind of feel with a Hindustani twist.) But without the influence of my wife I would not be watching any 3-hour chick-flicks (I've fallen asleep more than once. :-) )

  14. jinmtvt | | #14

    Dana : what brought you to visit/live in asia and the Netherlands ?? work ?
    what is it exactly that you do for a living ? ? :p

    My kids don't know much about vietnamese, only a few key words.
    Unfortunately, my wife's mother moved to Mass some time ago,
    and she would've been the one pushing around to have them learn.
    At least they'll probably be better than me at engrish and they seem to be picking up french
    faster than their toys in the living room :p

  15. Expert Member
    Dana Dorsett | | #15

    Electrical engineering jobs can sometimes take you places...

  16. Donny88 | | #16

    Does Dana Dorsett still offer information? I am hoping that 3-1/2" of open cell spray foam in a 2x4 wall with R3 Zip panel will be enough to stop condensation issues. My RES Check works but I'm concerned about condensation. I'm in a 5a climate zone.

    1. Expert Member
      Dana Dorsett | | #17

      To meet code it needs an interior side Class-II vapor retarder for that stackup to work with only R3 on the exterior of 3.5" of open cell foam. Since the open cell foam is a reliable air barrier it's not as risky as with fiber insulation. Vapor barrier latex primer is pretty cheap & reliable.

      It takes R5 on the exterior to meet the IRC prescriptive for zone 5 without tighter vapor retardency on the interior.

      1. Donny88 | | #18

        Thank you Dana, I am dealing with a very narrow house so every inch is important. My gut feeling is that 3-1/2" of open cell with either R3 or R5 continuous rigid board on the exterior is a better way to go than 3" of closed cell. As you have pointed out, the loss of of R-value as the temperature drops concerns me.

        I've been using both since 2002. In one case I used 3" of closed cell with 2" of Sto efis system foam. In my experience all of that insulation didn't make much of a difference. I believe the roof is the most important area to contain heat loss which I will have R49 open cell. My thoughts are based on experience and not scientific calculation though. I would appreciate your opinion on which you believe is the better way to go with 2x4 walls? I do have minor shear wall areas but I believe my structural engineer and I can work through that if I go with the Zip system.

        1. Expert Member
          BILL WICHERS | | #19

          It’s only polyiso that has the “R value drops with temperature” issue. Closed cell spray foam does not have that problem.

          Is there any particular reason you want to use R49 worth of open cell spray foam in your attic? Usually spray foam is only used in very specific circumstances (non-ventable roof, mechanicals in the attic), as there are other cheaper ways to get the same or sometimes even better performance.

          BTW Dana, I did not know you were a fellow EE :-)


          1. Expert Member
            MALCOLM TAYLOR | | #20


            Don't let the bio fool you. Dana Dorsett is the collective pen-name of a large group of building scientists who use GBA to hone their skills. There no way one man could assemble the amount of useful information Dana regularly does in response to questions.

          2. Expert Member
            BILL WICHERS | | #21

            That makes sense. Dana posts in many other forums too, so must not need any sleep. But if he’s not actually just one person...

            Perhaps “Dana Dorsett” is actually a complex, intelligent search engine that automatically runs queries against a vast database of building science knowledge as part of a clever clandestine project to encourage more durable and efficient structures?

            Hmmmm.... ;-)


          3. Expert Member
            Dana Dorsett | | #23

            >"It’s only polyiso that has the “R value drops with temperature” issue."

            And it's not always relevant in zone 5A, since it's the average temperature through the foam layer averaged over the season that really matters, not the exterior temp or the temperature extremes.

            Not all polyiso is the same either. The straw-man product that everybody in the industry likes to kick the stuffing out of is 2lbs density roofing polyiso, which has a wilder-wackier derating curve than most 1lb density sheathing polyiso.

            >" My gut feeling is that 3-1/2" of open cell with either R3 or R5 continuous rigid board on the exterior is a better way to go than 3" of closed cell. As you have pointed out, the loss of of R-value as the temperature drops concerns me."

            Listen to your gut. The loss of thermal bridging with a closed cell between the studs solution is a FAR bigger performance hit than any temperature derating for polyiso. Do the math:


            >" Dana posts in many other forums too, so must not need any sleep."

            I'm a parent- I'm not ALLOWED to sleep!

            Does snoring through Hindi chick-flicks or K-Dramas, dreaming in some other language count as "sleep"? :-) Meri patni mahat Shah Rukh Khan fan hain- mein na. Kya karu? "Rab ne bana di jodi!", shyad? I still can't dance, but often catch the lyrics- there are some great ballads in some of those movies.

            >"BTW Dana, I did not know you were a fellow EE :-)"

            I'm a physics & math guy by education, falling into EE as career almost by accident. (Long story, along the lines of "...a tale told by an idiot".)

          4. Expert Member
            BILL WICHERS | | #26

            I listen to Russian music videos at night with my daughter so some similar language stuff there :-) when children are young, it’s easier for them to learn other languages, and if they learn a second language before they’re around 5-6 or so it will always be easier for them to learn another later. Something about brain development. My daughter right now is always talking about a “yellow dress” because that is what Вера Брежнева (Vera Brezhneva) wears in her video Близкие люди (blizkie ludi, “close people”). It’s nice that autocorrect works in other languages when using the different character set because my Cyrillic spelling skills suck :-) My wife is fluent in three languages, Russian one of them, so we have an in-house tutor.

            I totally here you on never getting sleep! We’re in the “no naps after 5pm or so” because that means not sleeping until 2-3am.

            I do hope to be able to generate some data showing the polyiso derating in cold temperatures when I have my test rig built. I have a design done (mostly), but need to build the thing. I’ll have to be sure to test some roofing polyiso too — I was not aware it was significantly different in regards to derating compared to the “regular” foil-faced stuff. My rig will allow and cold and hot side temperatures to be set down to around -50C or so, so I should be able to test under just about any set of conditions needed.


  17. Donny88 | | #22

    Guys, thank you for you feback. Generally in my town, r49 in a furred out 2x12 bay meets our local requirements and saticfies our rescheck. If there is a better less expensive way to achieve that I'm all ears?

    Getting back to the walls though, I'm not a big proponent of closed cell throughout the house. In my opinion houses have almost become to tight. The house becomes a big vacuum similar to a balloon. The house pressure varys depending on different barometric pressures. Between the negative pressure and the ventury effect, any areas of the vulnerabilities of air leaks accelerate and escalate with potential mold issues and terrible drafts. I guess I'm a bit old school and believe a house should breath somewhat. I've used erv's and in my experience, even doubling the amount of units I do not feel they are as effective as they are made out to be. Other than condensation, I believe there is a point where over insulating walls become situation of diminishing returns. Again, I base this on many years of experience not scientific analysis.

  18. Expert Member
    Dana Dorsett | | #24

    >"I guess I'm a bit old school and believe a house should breath somewhat. "

    Houses need to "breathe" water vapor to get rid of it, not air, and allowing air to move through the insulation layers often creates moisture problems. Open cell foam is air tight, but fairly vapor open, and works fine in zone 5 if taking proper design measures on other layers to manage the vapor retardency and protect the susceptible materials.

    Humans need to breathe air, and a leaky house is one of the lousiest approaches to ventilation, since the paths aren't always known-clean, and may not enter or leave where it's needed the most. With an air-tight house and a mechanical ventilation system the appropriate amount of known-clean air can be delivered where /when it does the most good.

    1. maine_tyler | | #25

      >"Houses need to "breathe" water vapor to get rid of it, not air..."

      Not trying to go down the rabbit hole here (though I do like rabbit holes), but do you feel like the proverbial Styrofoam cooler (foam wrap jobs... PERSIST type stuff) ultimately face challenges by way of not 'breathing vapor'?

      I realize ventilation will chop away at removing the moisture, but does it create a need to increase ventilation rates and/or generally cause higher indoor humidity than assemblies with more permeance, other things (insulation levels and air-tightness) being equal?

      1. Expert Member
        Dana Dorsett | | #27

        >" you feel like the proverbial Styrofoam cooler (foam wrap jobs... PERSIST type stuff) ultimately face challenges by way of not 'breathing vapor'?"

        Not at all. If you install a true vapor barrier on the interior side of a PERSIST assembly the structural sheathing is at risk. It still needs to "breathe" vapor in at least one direct to have reasonable moisture resilience over the long term.

        Have houses built with perfect moisture traps ever been able to survive? Sure, but it's not even up to the "good" in the "good/better/best" way build or spec a wall or roof assembly. (Murphy's Law, et al.)

        1. maine_tyler | | #28

          Gotchya, yes the 'assembly' needs to 'breath vapor,' but this can be 'to the inside' which is ultimately removed via ventilation in this case.
          I was thinking of breathing in this case as being more of an exchange between inside the house and outside, in which case I was considering foam coolers not to 'breath' vapor. Breathing 'to the inside' will ultimately have its exchange with the outside via the ventilation of course. Thanks for the clarity.

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