Home  5  Books  5  GBEzine  5  News  5  HelpDesk  5  Register  5  GreenBuilding.co.uk
Not signed in (Sign In)

Categories



Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

PLEASE NOTE: A download link for Volume 1 will be sent to you by email and Volume 2 will be sent to you by post as a book.
Buy individually or both books together. Delivery is free!


powered by Surfing Waves




Vanilla 1.0.3 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to new Forum Visitors
 Join the forum now and benefit from discussions with thousands of other green building fans and discounts on Green Building Press publications: Apply now.

The AECB accepts no responsibility or liability for any errors or omissions in the content of this site. Views given in posts are not necessarily the views of the AECB.



General: Useful list of U values of common and, further down, less common materials

Bottom of Page

1 to 30 of 47

  1. <
  2. 1
  3. 2
  4. >
    • CommentAuthorRobinB
    • CommentTimeMar 19th 2013 edited
     
    Thank you North Herts!

    http://www.north-herts.gov.uk/gold_guide_tech_note_10_2010-3.pdf

    Yes, I know it's 2010, bat AFAIK the U values still hold. Maybe there's a newer one someowhere...
  2.  
    Great pdf. Well found :)
  3.  
    The holy grail still is to find a good list of uvalues for UNcommon/eco building materials :(
    •  
      CommentAuthorjoe90
    • CommentTimeMar 20th 2013
     
    I have read that strawbale is about 0.15 but no data to prove it. anyone?
    • CommentAuthorTimber
    • CommentTimeMar 20th 2013
     
    From what I have seen, straw bale is 0.25 to 0.2 depending on specifics of the straw you are using.
    • CommentAuthorRobinB
    • CommentTimeMar 20th 2013 edited
     
    more info on straw bale U values here (not 100% conclusive)
    http://www.aecb.net/forum/index.php?topic=1088.0

    ps Someone please remind me how to post a working link!
    • CommentAuthorGotanewlife
    • CommentTimeMar 20th 2013 edited
     
    Posted By: RobinBSomeone please remind me how to post a working link!

    Just press the 'text' button immediately below where you enter your comments....but then any quotes you make won't work of course - tis one or t'other
    • CommentAuthorRobinB
    • CommentTimeMar 20th 2013
     
    Thanks gotanew, let try it

    more info on straw bale U values here (not 100% conclusive)
    http://www.aecb.net/forum/index.php?topic=1088.0

    ps Someone please remind me how to post a working link!
    • CommentAuthorRobinB
    • CommentTimeMar 20th 2013
     
    Hey it worked! I always thought text was for plain text only! thanks
    • CommentAuthorEd Davies
    • CommentTimeMar 20th 2013
     
    Also, you can go back to old posts (only your own, of course) and edit them. Edit can include changing the format. Use the edit link top right of the post (next to the quote link) which only appears on your own posts.
    •  
      CommentAuthordjh
    • CommentTimeMar 20th 2013
     
    The FASBA link in the AECB thread has the correct values for the German certification. It counts as an ETA, IIRC. There are also similar certifications in other European countries, such as Denmark. The certificates are available online if you poke around a bit. Sorry, I don't remember the URLs or have the certificates to hand at the mo.

    Classic strawbales are 14" x 18" (356 mm x 457 mm). You also need to allow for the render; and don't forget that bales are anisotropic. Not all balers are created equal!
    • CommentAuthorRobinB
    • CommentTimeMar 20th 2013
     
    BRE thinks UK dimensions for straw bales are 990 รƒโ€” 500 รƒโ€” 375 mm as you say not all equal.
    • CommentAuthorMike George
    • CommentTimeMar 20th 2013 edited
     
    Posted By: bot de pailleThe holy grail still is to find a good list of uvalues for UNcommon/eco building materials :(


    Here's one I did earlier though it is designed for insulation upgrades to typical wall types:) Maybe of some use.

    k-values may have changed slightly and thermal bridging is not considered

    The k-value for straw bale is around 0.09W/mK so pretty close to the strawboard listed
    • CommentAuthorRobinB
    • CommentTimeMar 21st 2013
     
    That's great Mike, thanks!

    It clearly shows the immediate benefit of adding even a modest amount of insulation to an uninsulated wall.

    If only i could change the title of the thread to common and uncommon.
  15.  
    You can change the title. Just edit your first post:)
    • CommentAuthorRobinB
    • CommentTimeMar 21st 2013
     
    Well I never! I've just done it. thanks

    I think there are a few other threads which would benefit as they morph from, for example, the original subject of Ventive, to MVHR, to FiWi, and so one.
    •  
      CommentAuthordjh
    • CommentTimeMar 21st 2013
     
    Posted By: RobinBBRE thinks UK dimensions for straw bales are 990 รƒโ€” 500 รƒโ€” 375 mm as you say not all equal.

    BRE thinks lots of things that are wrong.
    •  
      CommentAuthordjh
    • CommentTimeMar 21st 2013
     
    Posted By: Mike GeorgeThe k-value for straw bale is around 0.09W/mK

    Only if you use it the wrong way round and add a 12% margin for error!

    "Laut der in Deutschland nun geltenden allgemeinen bauaufsichtlichen Zulassung Z-23.11-1595 vom 13.02.2009 gilt ein Lambda-Rechenwert in Halmrichtung von 0,08 W/mK und quer zur Halmrichtung von 0,052 W/mK."

    And those are the values with moisture content already accounted for, not the better measured values.

    If you think about it, it would be reasonable to expect the lambda values of all the cellulose insulations to be pretty similar except where there are obvious reasons for differences.
  19.  
    @Mike George

    You appear to give a rather low value for mineral wool at 0.033W/mK

    North Herts gives a value of 0.038W/mK which appears to reflect the figures I have seen on the various mineral wool data sheets which depending on the product tend to range between 0.037W/mK and 0.044W/mK

    Your value for glass fibre seems a little too good also.
  20.  
    'Mineral wool' (GF or rockwool) typically 0.040-0.044.
  21.  
    Posted By: Chris P BaconYou appear to give a rather low value for mineral wool at 0.033W/mK
    Glass mineral wool is available in various grades from 0.032W/mK for high density cavity wall batts/rafter roll through 0.038-0.040W/mK for medium density roll to 0.044W/mK for the lowest density loft roll. I've seen one product in France at 0.030W/mK at 50mm thickness, but I've not seen it in the UK, it is foil faced & I'm not sure whether it assumes an air gap to one face.

    David
    • CommentAuthorDarylP
    • CommentTimeMar 21st 2013
     
    If it is the St. Gobain product, I think it does rely on that!
    St. Gobain said they could not import it into the UK because of they way BBA/BRE test, using the 'hot box', it would not stack up....? 0.032 is the best you can get mineral/glass wool-wise.

    Cheers :smile:
    •  
      CommentAuthorfostertom
    • CommentTimeMar 21st 2013
     
    Posted By: DarylPcould not import it into the UK because of they way BBA/BRE test, using the 'hot box', it would not stack up
    Whattt?
    • CommentAuthorDarylP
    • CommentTimeMar 21st 2013
     
    T'is true, that is what the St. Gobain rep said to me, last year....!:shocked:
  25.  
    Posted By: djh
    Posted By: Mike GeorgeThe k-value for straw bale is around 0.09W/mK

    Only if you use it the wrong way round and add a 12% margin for error!

    "Laut der in Deutschland nun geltenden allgemeinen bauaufsichtlichen Zulassung Z-23.11-1595 vom 13.02.2009 gilt ein Lambda-Rechenwert in Halmrichtung von 0,08 W/mK und quer zur Halmrichtung von 0,052 W/mK."

    And those are the values with moisture content already accounted for, not the better measured values.

    If you think about it, it would be reasonable to expect the lambda values of all the cellulose insulations to be pretty similar except where there are obvious reasons for differences.


    I got the k-value for straw bale here Dave http://library.uniteddiversity.coop/Ecological_Building/strawbaleguide.pdf Page 6.
    • CommentAuthorMike George
    • CommentTimeMar 21st 2013 edited
     
    Posted By: Chris P Bacon@Mike George

    You appear to give a rather low value for mineral wool at 0.033W/mK

    North Herts gives a value of 0.038W/mK which appears to reflect the figures I have seen on the various mineral wool data sheets which depending on the product tend to range between 0.037W/mK and 0.044W/mK

    Your value for glass fibre seems a little too good also.


    Yes, perhaps some of the figures are out of date - the Reckonner was done some years ago now. As mentioned by others The k-values will vary by manufacturer and blowing agents etc have changed altering conductivities further. Easy to update though so if anyone wants to give me up to date numbers happy to oblige
    •  
      CommentAuthordjh
    • CommentTimeMar 22nd 2013 edited
     
    Mike George said: "I got the k-value for straw bale here Dave http://library.uniteddiversity.coop/Ecological_Building/strawbaleguide.pdf Page 6"

    Right, but although Barbara's a lovely lady, she's not the horse's mouth for European standards, especially in an old version of her book.

    If you want the official statement and have 7,67รขโ€šยฌ to spare, you can download it here:

    http://publikationen.dibt.de/service/history/zulhistory.aspx?zulnr=Z-23.11-1595&zul=Z-23.11-1595&language=en

    Or if you're willing to trust another source of the document, you can use:

    http://www.downloads.fasba.de/oeffentlich/pruefzeugnisse/z-23.11-1595(2009).pdf
    (n.b. the very wonderful forum software breaks the URL so you can't click it; you'll have to cut and paste)
    Section 2.2.2.
  28.  
    Whoa there... I believe you. :cool:I'm far from being any kind of expert in straw bale.

    I just thought it seemed like an authoritative source when I found it ... shows the dangers of googling really
    •  
      CommentAuthorSteamyTea
    • CommentTimeMar 24th 2013 edited
     
    Best to just check against Kaye and Laby.
    Silica has a lamba of 1.6, Air is 0.0241
    So a bit of Rockwool is mostly air at 0.033
    •  
      CommentAuthorfostertom
    • CommentTimeMar 24th 2013
     
    So how can any insulant have lamda less than 0.0241? I know this has been answered, but run me thro it again?

1 to 30 of 47

  1. <
  2. 1
  3. 2
  4. >
   
The Ecobuilding Buzz
Site Map    |   Home    |   View Cart    |   Pressroom   |   Business   |   Links   
Logout    

© Green Building Press