Window Tools, Inc. - Makers of the patented Jamp Spreader(R), the proven tool that makes it easy for homeowners to tilt their double-hung windows for cleaning.

Compression-jamb windows offer this superior seal. How? The sashes of compression-jamb windows slide on flexible vinyl jamb liners. In the interest of performance, these jamb liners not only press inward for a tight fit against the sash; they also feature vertical ribs that fit into matching grooves on the sides of the sash. This precisely-engineered fit between sash and jambs helps to provide a level of thermal efficiency that most other double-hung windows just can't match.

In addition, almost all compression-jamb windows offer a tilting-sash feature. This means that the two sashes can be tilted inward, allowing you to clean the outside glass surface from inside your home. This feature saves you from the inconvenience of washing your windows from outside. It is an especially significant feature for owners of multiple-story homes, where outdoor window-washing can mean risking a long fall to the ground from a ladder. While a number of current windows provide this tilting feature, however, just remember that not all tilting-sash windows are created equal. Industry performance tests show that compression-jamb windows, as a class, are far superior to most others.

Due to their snug-fitting, interlocked sashes and jambs, compression-jamb windows naturally do offer some resistance to tilting. For the sashes to be tilted, the flexible jambs must first be spread apart so that their vertical ribs disengage from the channels in the sashes. While the jambs are being held apart, the tops of the sashes are next pivoted inward. As you can imagine, this "push-apart-while-pulling-in" procedure can pose somewhat of a challenge to the unpracticed homeowner.

That's where The Jamb Spreader comes in....

The market currently offers a number of different double-hung window types for new homes and for replacement in older homes. "Double-hung" windows are so called because they are comprised of a rectangular outer frame which encases two (or "double") window sashes. These two sashes slide up and down within the frame so that the homeowner can open his/her windows for ventilation.

The double-hung window type is a very traditional one, as its basic design (two movable sashes) has been used in homes for well over a hundred years. In today's compression- jamb windows, however, one can easily see how markedly the double-hung design has evolved since its beginnings. The first compression-jamb windows were introduced more than twenty-five years ago, and their sound design is what has given them such longevity in the marketplace. Quite a number of reputable companies manufacture compression-jamb units. You can see a listing of more than 20 of these companies and hyperlink to their websites on our Manufacturers Page.

Most consumers who have ever engaged in comparison-shopping know that some products are simply designed better than others. Windows are no exception to this fact. Obviously, one of a window's most important functions is to insulate your home from the outside elements, so the seal between the window sashes and jambs is crucial. If this seal is loose or inconsistent, the window will not serve as an effective thermal barrier. So, it follows that the best-performing double-hung windows necessarily have the tightest, most secure seal between the sashes and the window jambs.