Double Hung Window Replacement
I am concerned about replacing double hung windows in my Victorian house that was built some time between 1895 and 1900. My daughter wants to keep everything authentic, but air infiltration is ghastly. When the wind whips up, air travels around the window trim, through the side cavities (where the cords and weights are) and then into the room.
I had thought about vinyl windows, but my daughter insists that this would not be authentic. My next thought was to suggest leaving the original wood windows and replace them with vinyl frames. I was kind of hoping she would go for this one.
In a double hung window, air can enter from four places:
- between the frame of the window and the frame of the house at the exterior wall;
- between the frame and the top window;
- between the frame and the bottom window; and
- at the point where the top and bottom windows join.
If wind-forced air can’t travel beyond these points it can’t get to the cord-weight cavity.Caulking the window trim at the exterior will usually take care of infiltration between the window and house frames. The other three areas can be handled with weather stripping. The trick is to weather strip the window so that the material isn’t readily visible.
Add three strips of insulation to the outside surface of the top window at the very edges of the top and two sides. Do the same thing to the bottom window adding a fourth strip at the bottom edge where it contacts the sill. The tough part is removing the windows to get the weather stripping on. In some instances the trim that holds the windows in place will have to be milled to handle the extra window thickness that results from the addition of the weather stripping. The windows should fit tightly and a water-based silicone lubricant should be sprayed onto the weather stripping to ensure smooth operation.
When the windows are closed the insulation will be invisible. When the windows are opened some of the insulation will show, but if the color of the insulation matches the color of the window frame, it will be unlikely that anyone will notice.
After you’ve weather-stripped, watch how your heating bill drops.