WPSC

WPSC Standard, draft

Number:
Update: 12/13/12
Author: John Leeke
Contributors: Joy Sears
References: Window Repair, Rehabilitation, and
Replacement, Peter Baker, U.S.D.o.E, Nov. 2011, p. 11.
Historic HomeWorks Forum website: Acquired on 7/7/11, http://historichomeworks.com/forum/viewtopic.php?t=193

Title of Treatment: Interior Air Panel, custom made onsite
Class of Treatment: [ ] Maintain, [ ] Stabilize, [ ] Repair, [X] Upgrade, [ ] Exception
Type of Treatment: [ ] Conservation [ ] Traditional, [X] Contemporary

Condition to be Treated: window is cold and drafty in the winter and allows too much heat to escape to the outdoors

Description: A simple wood frame is covered with plastic film and a gasket or weatherstripping is fitted around the edges. Film is applied on one or both sides of frame. Film on both sides provides additional thermal performance by enclosing an additional air space. The whole panel is sized to fit snugly into the reveal of the window, at the inside of the window and up against the sash. The seal is so good that when the wind blows the panel may pop right out, so it is held in place with screws or other fittings depending on the configuration of the window. This low-cost window upgrade improves energy performance. Occupants comment on improved comfort near the window and less street noise coming through the window. Air panels should only be used during the heating or cooling season and removed for at least two months twice a year to allow any moisture buildup in the wooden parts of the window to dry out, preventing wood deterioration.




Typical Procedure:
1. Measure window openings
2. Select gasket or weatherstripping system
3. Plan the size of the frame
4. Make up wood frame
5. Check the fit in the window
6. Apply the film and gasket
7. Staple on pull tabs near bottom of frame stiles
8. Install the frame in the window
10. Shrink the film with a hair dryer or hot air gun
11. Fasten the frame in the opening
12. Test and tune up for ease of removal and installation

Materials:
• Clear straight-grained wood for frame
• Screws, wallboard style, 2 ¼” or 3” depending on width of frame stiles, 6 per panel
• Sandpaper, 120 grit
• heat shrink film: graphics grade, polyolefin, Acid Free, 100 Gauge (1 mil) thick
• 5/8" diameter compressible foam backer rod with full-round to be cut in half
• Double-stick pressure sensitive tape: acrylic film, acrylic adhesive
• 2" wide clear adhesive tape: acrylic film, acrylic adhesive, 3 mil thick, ultra-violet light resistant

Quality of Results:

Best Work: a tight fit around entire perimeter, horizontal frame bar aligns with meeting rail, a clear view is visible through the film, the film itself is un-noticeable

Adequate Work: a tight fit around entire perimeter, horizontal frame bar aligns with meeting rail, slight wrinkles may show in plastic film

Inadequate Work: gaps show around perimeter of panel between the gasket and the window


<This is a Proposed Standard Treatment. Click on "Post Reply" below to comment or ask questions.>

I think this is a great inexpensive idea for renters in old buildings and for winter use on hard to reach or multi-story residences. The main caveat is that once installed that they have to pay attention to any moisture issues that might develop as they will need to be removed at some point either to clean the window or dry out the window. To alleviate most excessive moisture issues, kitchens, bathrooms and laundry rooms need to be vented to the outside regardless of climate. Remember you still have to pay attention to maintenance and repair of the prime windows.

I made a small portable version of this to take to historic home and energy efficiency talks as a prop.

Joy:

That's a good point about trapping moisture. I've added a note to remove them seasonally so the woodwork of the window can dry out if there is any moisture buildup.

_________________
John
Standards Co-Founder
Standards Editor

http://www.HistoricHomeWorks.com