What insulated window covering would you recommend in The Blue Zone?
We live in a small (675sq. ft), tight, well-insulated house with many south facing window in west central Wisconsin. Our double paned, argon gas filled south facing windows heat the house for 10 hrs. on sunny days, even on below zero days. Of course, the windows lose much heat at night. We have in-slab hydronic heat running on off-peak electric through a 10kw micro-boiler, usually running at a water temp of 93-102 frht., which is very comfortable.
We are considering making thermal coverings of quilted fabric and have looked at blinds with baffles. Our budget is tight. What window coverings are having the best results and are also convenient to use?!
In the sales literature for Hunter Douglas honey comb blinds they say it can add an R value of 5 or so. I have a hard time believing this given they don’t seal around the sides. Any opinions based on experience on this?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
I wouldn't try to make them. The only insulating window coverings that are effective slide in tracks so that they are air-tight. Otherwise convective loops can cause greater heat loss than if there were no coverings.
Unless you're skilled enough to make something like the Window Quilt, I would recommend purchasing them.
I have read about insulated interior thermal shutters several times, typically made from luan and foam board. If someone was skilled and thoroughly detailed about weatherstripping, could these offer another solution? I have no direct experience with this method and would like to hear from those who have had experience.
Thanks Robert.
I see Window Quilt also has a velcro option, without valance, which costs less.They say it performs as well as the tracked options.
In the past I've put 2" EXP or Polyiso foam boards into windows at night for insulation. They did provide good insulation, but because they were not airtight the window glass often chilled below the freezing point, frost formed, then melted in the sun, which created the unintended consequence of water puddles on the windows sill. So I'm still looking for a good window insulation scheme.
a track system or velcro strips to keep the blinds tight is the key. We'll be making some for our double pane, argon filled windows as well.
http://www.ccathsu.com/files/handouts/Thermal%20Curtains%20-%20Making%20Your%20Windows%20Warm.pdf
http://www.ehow.com/how_4834338_up-insulated-thermal-roman-shade.html
http://www.builditsolar.com/Projects/Conservation/ThermalShades/ReflectexShade.htm
I am in a similar place as Edward in terms of wanting to improve interior window coverings. I came across this product on the net: http://www.blindschalet.com/energytracktanslucent38.html which seems to mostly seal up the sides around the blinds.
Does anyone have any experience with these tracks? All things being equal, what are the relative merits of the full quilt designs vs. the double cellulars?
As I said, with the requisite skill it's certainly possible to fabricate these, but there are commercial products which have worked for decades and are guaranteed. My neighbor used to produce the only commercial competitor to Window Quilt, the Comfort Shade, but stopped production after the 1970s Oil Shock fuel prices settled back down and no one was interested in energy efficiency (but his 30 year old shades are still working in many school buildings).
The key is a side track or seal, but most importantly a bottom and top seal to prevent convective loops. The best materials to use would include a vapor barrier, a thermal barrier and a radiant barrier.
Another option is to use removable interior insulated covers, which are installed and removed by a quarter turn of a removable crank. The complete instructions to make them are located at http://www.jcrondiy.com .The advantages are (1) good R-value (9 - 16); (2) seal well; and (3) you don't need to modify your window frames.
Here is a link to a good discussion about insulated window covers...Check out what green building pioneer Rob Dumont has to say...
http://greenedmonton.ca/mcnzh-window-coverings
For the DIY person, (Handy with a sewing machine) https://warmcompany.com/ sells a multilayer quilted fabric You can optionally add a decorative fabric on the room side. One of the layers is aluminium coated mylar which acts as an infiltration barrier. The covering seals by using strip magnets on the wall and embedded in the edge of the fabric. The easiest system to make is roman blinds. Looking at the plans, I think this one would seal best too.