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u vlaue

  • 08-12-2014 02:41AM
    #1
    Registered Users, Registered Users 2 Posts: 25


    hi i am just wondering if a u value of .19 is good enough for external walls?


Comments

  • Moderators, Home & Garden Moderators, Science, Health & Environment Moderators Posts: 19,290 Mod ✭✭✭✭DOCARCH


    Depends....for what?


  • Registered Users, Registered Users 2 Posts: 12,717 ✭✭✭✭galwaytt


    Simplistically put, yes - But at least as important is airtightness.

    A good u-value with no stated, or poor airtightness means nothing.

    What airtightness figure are you aiming for ?

    Ode To The Motorist

    “And my existence, while grotesque and incomprehensible to you, generates funds to the exchequer. You don't want to acknowledge that as truth because, deep down in places you don't talk about at the Green Party, you want me on that road, you need me on that road. We use words like freedom, enjoyment, sport and community. We use these words as the backbone of a life spent instilling those values in our families and loved ones. You use them as a punch line. I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the tax revenue and the very freedom to spend it that I provide, and then questions the manner in which I provide it. I would rather you just said "thank you" and went on your way. Otherwise I suggest you pick up a bus pass and get the ********* ********* off the road” 



  • Subscribers, Paid Member Posts: 43,779 ✭✭✭✭sydthebeat


    hi i am just wondering if a u value of .19 is good enough for external walls?

    the "backstop" u value (the one you cant go over) is 0.21 so it complies with that one small aspect.

    however, the whole specification needs to be taken together to see how it works.

    personally id consider a 0.19 u value to be just about barely adequate, certainly not special.


  • Registered Users, Registered Users 2 Posts: 12,717 ✭✭✭✭galwaytt


    sydthebeat wrote: »
    the "backstop" u value (the one you cant go over) is 0.21 so it complies with that one small aspect.

    however, the whole specification needs to be taken together to see how it works.

    personally id consider a 0.19 u value to be just about barely adequate, certainly not special.

    Disagree.
    Without an airtightness value attached it means nothing. Consider: u-value is directly measurable in €€€€. That is, in materials.

    Airtightness on the other hand does not and is indicative of quality of build.

    I know of several houses with 0.17 that function with no mechanical heating at all. 0.19 is not that far removed. It will still need very little heat and yet be economic to build.

    Ode To The Motorist

    “And my existence, while grotesque and incomprehensible to you, generates funds to the exchequer. You don't want to acknowledge that as truth because, deep down in places you don't talk about at the Green Party, you want me on that road, you need me on that road. We use words like freedom, enjoyment, sport and community. We use these words as the backbone of a life spent instilling those values in our families and loved ones. You use them as a punch line. I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the tax revenue and the very freedom to spend it that I provide, and then questions the manner in which I provide it. I would rather you just said "thank you" and went on your way. Otherwise I suggest you pick up a bus pass and get the ********* ********* off the road” 



  • Subscribers, Paid Member Posts: 43,779 ✭✭✭✭sydthebeat


    So are you saying it's a great u value, an ok one or a bad one?


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  • Registered Users, Registered Users 2 Posts: 12,717 ✭✭✭✭galwaytt


    sydthebeat wrote: »
    So are you saying it's a great u value, an ok one or a bad one?

    I'm saying it means nothing without a matching airtightness figure.

    Ode To The Motorist

    “And my existence, while grotesque and incomprehensible to you, generates funds to the exchequer. You don't want to acknowledge that as truth because, deep down in places you don't talk about at the Green Party, you want me on that road, you need me on that road. We use words like freedom, enjoyment, sport and community. We use these words as the backbone of a life spent instilling those values in our families and loved ones. You use them as a punch line. I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the tax revenue and the very freedom to spend it that I provide, and then questions the manner in which I provide it. I would rather you just said "thank you" and went on your way. Otherwise I suggest you pick up a bus pass and get the ********* ********* off the road” 



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