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This Page revised November 5, 2009

 

Replacing old windows using the Anderson "Insert" product...

Comments on replacing the original window sash and window counter weights with an Anderson Insert window sash system, along with removing 1960's vintage aluminum triple-track storm windows, to greatly improve the energy efficiency of these north facing windows.

 

Why, after advocating old window restoration, are you replacing these old windows with new ones?

After a lot of work reglazing and weather stripping these single window pane sashes, the non-insulated window sash weight pockets (cavities) are simply incapable of dealing with strong winter weather coming from the north, as are the triple-track storm windows, in terms of the total energy efficiency that they don't provide. Having struggled with this cold windows and wall winter problem for the past 26 years, it was time to deal with it, involving a replacement window system.

 

Original 2-over-2 (on the left) north facing bedroom windows, the only 2-over-2 windows in the house, now being replaced with 6-over-6 Anderson Insert double glazed sashes and tracks to fit the existing frame and to match the rest of the house windows, which are 6-over-6, originally installed in 1927.

 

Note the very small amount of gap between the Anderson track and the original window frame. Careful measurements and discussion about fitment with your local supplier is important, as is the fact that these old window frames are still square. My supplier is Loudoun Lumber, who has suggested and supplied materials for a number of our other house projects and have been great to work with.

 

After the old aluminum triple-track storm window frame is removed, you can see that the Anderson Insert fits very close to the old exterior window stops, as shown above. (this was my test fitting and no sealent had yet been applied to the window perimeter) Nothing was specified as a measurement in terms of the exterior window stop bead size or position, but Anderson clearly has done some homework in making sure these inserts fit older windows and their typical stop bead size and placement. I did specify the original sub-sill pitch angle for the new Anderson Insert window sill, which fits perfectly with the old sub-sills... which are still level after all these years.

 

Test fitting of the Anderson Inserts completed, the windows will now be removed to insulate the empty window sash weight pockets and to make the final shimming for alignment and completion, including sealing the exterior perimeter of the Insert window with the original external window stops.

 

After having removed the aluminum triple track storm windows, to permit the test fitting of the Anderson Insert windows, a careful inspection of the original exterior window stops showed that they needed repair, due to failed caulking/sealant over the years. I hate to see the use of silicone sealant used on bare wood, which some brands say is okay, or on top of failing painted surfaces. It fails to actually seal and leads to water damage, which I saw too much of during my widow restoration work. It is not the "magic" sealant the makers would like you to believe. Not in my experience, anyway. Nothing is ever simple once you get started on a project such as this, is it.

 

While repairs and primer is drying on the exterior window stops, I filled the old window counter balance weight pockets with insulation, starting on the more difficult one, which could not have its face trim removed, because about 2/3 of it is covered by the wall. I had to carefully "thread" the insulation into the cavity, all the way to the pulley holes at the top of the window frame.

 

The center and right side cavities were much easier to insulate, since the face trim pieces could be carefully removed and replaced.

 

With the outside trim cleaned up and primed, the window perimeter has been sealed and painted, resulting in a weather proof installation with a nice clean look, not involving plastic trim filler pieces, but using only the old original exterior trim pieces. I like the look and will no doubt like the energy efficiency improvement. It is also a much quieter room, with the window weights gone and the cavities filled with 6-inch insulation. Anybody need some window weight pulleys?

 

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