Wright On Sustainability

Passive House Planning & Permaculture Design

  • Sep 27

    I reran the 2010 “Design Boundaries” study in Portland Oregon climate, for 3 different window performance levels, to get an idea of how much the design space is constrained by not using Passive-House-grade windows, which one might be tempted to do based on current cost difference.  (This does not take into account the lower interior comfort effect of cheaper windows, nor any added air-sealing risk.)

    As in the 2010 study, the things that are held constant are the R-values of the walls (66) , floor (71), and roof (89), the HVAC and appliance efficiencies and so on.  The windows are a standard 3×5 feet.  The things that vary are the length and width of the building, number of stories up to 4, orientation, site solar access, and the window-to-wall ratios on the North, East/West, and South.  Altogether 18432 cases are generated and automatically run through PHPP.  The results can then be filtered to see how many cases meet the Passive House performance criteria, and what are the easiest and toughest cases.

    The three window performance levels (all triple-pane) were:

    • Optiwin (Passive House certified window from Germany)
    • vinyl with high solar heat gain glass e.g. Cardinal LoE 180, and
    • vinyl with low solar heat gain glass e.g. Cardinal LoE 272.

    From some angles the situation doesn’t look too bad, but when I restricted it to 4-person houses (1300-1700 sf of Treated Floor Area), there were 10 times as many Passive House cases with the good windows than with the not so good.   To save that window money you’ve got to accept some design constraints is the upshot.  Here’s some charts:


  • Sep 27

    Our mainstays are the insulated fiberglass peoples:

    Thermotech Fiberglass and Serious have provided thermal performance data, and have supplied windows for Passive House projects.  I don’t know of any Passive House projects that have actually used Duxton or Accurate Dorwin. Inline may be supplying their frames. Duxton uses AFG, Cardinal, or PPG glass.  Not clear where A/D are getting their glass.

    On the wood window front, euro-style manufacturer HH Windows out of Seattle might be suitable; they can use Cardinal LoE-180 triple pane glass, and their frame U value is about 0.273 Btu/h.ft2.F.  It is rumored that THERM calcs are available upon request.

    I searched the R-5 windows program web site for residential, new-construction, casement windows deliverable to Oregon.   The following companies came up:

    • Amerimax
    • Four Season Sunrooms
    • Jeld-Wen
    • MI Doors and Windows
    • Monda
    • Ply Gem

    If any of these companies can put some flavor of Cardinal 180 triple-pane glass instead of the usual 366 (low solar heat gain) we might have a very cost-effective nigh-Passive House window at least for northwest marine climate.

    (Milgard and Atrium have told us they cannot offer it at this time.  This appears to be at least partly a regulatory issue, they don’t have NFRC ratings of their windows with this glass and it would cost a lot to recalc the whole product line.  For Portland at least, the Alternative Technology Advisory Committee might offer a way forward.  Also, for Passive House projects we aren’t generally interested in sliders or single-hungs because they don’t air-seal well enough.  Casement, tilt-turn, and fixed would be a good start.)

    I also asked Cardinal Glass if they could point me to manufacturers who could deliver a window with1 3/8 inch Lo-E 180 glass to the Pacific Northwest.  I got a call back from the Hood River sales manager.  He suggested:

    For wood windows:  Jeld-Wen custom wood window division

    For vinyl windows:

    • Vinyltech (British Columbia)
    • Innotech (British Columbia)
    • Mercer (Beaverton OR)
    • VPI (Spokane WA)

    Currently available Imports from overseas / rest of world, known to the Watch to have Certified Passive House Windows.

    Hi Graham-The REHAU Geneo PHZ series is a PHI certified window with German
    profiles that are stocked in Canada and now available for fabrication
    in the US.  The frame is made from RAU-FIPRO, a high-tech composite
    that was developed for the aerospace industry and is supposed to
    combine the strength of fiberglass with the weldability of vinyl.West Coast Vinyl Windows (WCVW) is the fabricator down in the LA area:
    http://www.westcoastvinylwindows.comPremier Window Group is the representative in the Seattle area:

    Here is some REHAU product data:

    and the PHI certificates:

    WCVW also makes its own glass units.  I’ve been told they have access
    to PPG Sungate 400 and is the only US fabricator authorized to use the
    Swisspacer listed in the PHI Certification.  They haven’t priced the
    windows yet, but expect them to be close to fiberglass.  I worked with
    both PWG & WCVW on a recent window replacement of 12-story apartment
    building here in Portland and found them great to work with.


    Non-Passive-House-Certified (or status-unknown) Imports of interest:
    All window manufacturers serving the North American Passive House market are beseeched to provide frame performance and glazing options data in the following format suitable for entry into PHPP.  Energate and Enersign I think have the most exemplary PHPP data charts on their web sites.  Here is an Excel template with handy unit conversion tab.
    Manufacturers or anyone who has compiled data, I invite you to download the template, enter data, save-as .xls and re-upload to Google Docs with share setting “anyone with the link.”  I would suggest to use a separate workbook for each manufacturer’s info.  Then post the link as a comment below, and I can then install it in the Watch proper.
  • Sep 14

    Update 27 Sept 2011:  I spoke with the Hood River Sales Manager for Cardinal Glass.  He said they can make a 1 3/8 inch triple pane LoE 180 unit with coatings on surface #3 and #5 instead of #2 and #5, for yet higher solar heat gain coefficient.  For 95% Argon fill it would have U=0.13 Btu/h.ft2.F, SHGC=0.59, and VT=0.70.


    Update 26 Sept 2011:  I did find a mother lode of Canadian manufacturers on the Insulating Glass Manufacturers Alliance web site.  On the Certification tab, IGMA Canada (IGMAC) has a Certified Products Directory which gives company names and some details of construction though not performance.  At a glance it looks like maybe 60% are double-pane and 40% triple-pane.  There are even two quadruple-pane products listed, from ECO Insulating Glass in Mississauga ON and from Northerm Windows (RAB Energy Group Inc.) of Whitehorse, YT.


    This is the current state of my knowledge.  Please comment if you have corrections.  I know of only a few North American manufacturers of residential window glass units:


    AGC Flat Glass North America

    AGC Residential Glass data sheet

    Formerly AFG Industries.  Now a subsidiary of Asahi Glass (Japan.) Their main factories are in Tennessee, Kentucky, and Kansas.  They seem to be unaware of Passive House.  They have double-pane units but no triple.


    Cardinal Glass Industries home page

    Cardinal Glass data table

    Cardinal specializes in Residential window glass.  Their HQ and R&D are in Minnesota and Wisconsin.  They have factories in 7 other states including Oregon.  They supply double and triple pane glass to multiple window manufacturers including Milgard, Atrium, and Inline / Cascadia.


    Guardian Industries home page

    Guardian residential glass for North America

    Guardian Europe coated lo-E glass

    Guardian is based in Michigan, and their European division makes the impressive Climaguard N3 also known as Flachglas which is Passive House certified.  However there is no evidence on their web sites that they are making or selling any triple pane units in North America.


    PPG Industries home page

    PPG Residential Glass home page

    The venerable Pittsburgh, Pennsylvania glass manufacturer.  They do not make multi-pane glass units themselves but they have a wide array of glass and coatings as well as a warm edge spacer.  They have a Find a Window Manufacturer page which turns up 9 or so listings for Oregon & Washington.  Their graphics and examples are all double-pane, BUT their window manufacturer support includes an online calculator which allows you to design a double or triple pane glass package and see what the center-of-glass U-value and SHGC would be.  (Similar to what the Lawrence Berkeley Lab WINDOW software does, but limited to the PPG catalog.)

    I made a triple pane with 0.60 SHGC and 0.15 U-value, see if you can do better!


    Serious Windows home page

    Serious Windows residential data sheets

    Serious makes both their windows and their glass in Sunnyvale CA.  The glass used to be called Alpen glass, and was purchased by Serious around 2008.  Their technology is 1-3 layers of suspended film in between the inner and outer glass panes.  These are the only North American glass manufacturers with the words “Passive House” on the their web site.