Pressing Matters: Inserting Indow Windows for Energy Efficiency

Indow Windows (Indow) is a Portland, Oregon, company that has developed energy efficient window inserts.

Indow owns at least one U.S. Patent and a pending patent application covering its storm window technology.  U.S. Patent No. 8,272,178 (’178 Patent) is entitled “Press-fit storm window” and directed to a storm window assembly comprising a transparent panel and tubes or gaskets for insertion into a window frame.

The tube (102) has a hollow interior and a channel groove that connects it to the panel (130).  The tube allows a pressure fit (350, 352, 354) into a window frame.

FIGS. 6(A)-6(C) show a molded tube corner piece which includes parallel plates (605, 615) with a gap (617).  Notch (643) facilitates better coverage and flexibility while find (641) provides improved adhesion and insulation.

FIG. 5 shows the corner piece being inserted into a window frame.

U.S. Patent Application Publication No. 2014/0174006 is a related application (continuation-in-part of a continuation-in-part) owned by Indow, which adds some new material to the original disclosure of the ’178 Patent.

According to the ’178 Patent, the invention is intended to supplement, rather than replace, existing windows:

The windows are not designed to replace existing windows, but rather to supplement them by creating a tight seal between the interior space or exterior space and the existing window.

The invention accomplishes this by creating outward pressure around the edge of the panel:

In one embodiment of the inventive press-fit storm window, a transparent panel of acrylic glass, such as PLEXIGLAS, glass, or other clear rigid material is held in place by the spring action created by a continuous (or partial, conceivably) round gasket (or other spring-like gasket), that creates outward pressure around the entire exterior edge of the clear panel (or the top, left, and right sides). The panel is held securely in place through a combination of this outward pressure and friction.

A press release emailed to me by the company notes that its compression tube requires no mounting hardware or track system. Significantly, the press release cites a U.S. Department of Energy study which found that installation of Indow Windows in a home in Seattle “led to a more than 20 percent reduction in heating, ventilating and air-conditioning use.”

The windows have gotten some recognition – according to the press release it has won a number of awards including the 2014 Top Product of the Year Award in the Environmental Leader Product & Project Awards.