Choosing the proper frame style when installing new windows

Last week, I told you how to measure for your vinyl replacement windows when replacing aluminum windows. Now that you're ready to order your new vinyl replacement windows, we need to talk about the different frame style options available. In most of the country your choices are limited to either new construction or replacement frames. New construction frames come with a nailing fin to attach the frame to the studs during the construction of the new home. The replacement frame is basically the new construction frame minus the nailing fin.
But in the west, where stucco homes are common, manufacturers came up with a third type of frame called a retrofit frame. The retrofit frame has a fin about 2 inches wide, located flush with the outside face of the window. This is the best choice when replacing old windows, but not all jobs will accomodate a retrofit frame application. So let's discuss how to determine which frame is going to work for you.
If you have a stucco exterior, retrofit is the way to go. You install the new window from the outside, and the flush fin covers the old aluminum frame that you are going to leave in place. Then you screw the new window in using deck screws through the side channels as well as the top header. We will get into more detail on the actual installation in a future article. If you have a stucco exterior, but there is a wood trim around the opening of the window where the flush fin would normally go, you can still use the retrofit style frame. You would need to remove the wood surrounding the opening, install the retrofit window, then purchase and install new wood trim. The old trim will no longer fit since the retrofit window frame dimensions will be larger in width and height than the old window frame. Another option is to install the retrofit fin on top of the wood trim. You can do this as long as the depth from the face of the wood trim to the point in the house of the innermost portion of the old aluminum frame is less than 3 inches deep. The reason is because a good quality retrofit window will have a 3 inch frame depth from the back of the flush fin to the innermost part of the frame. That innermost part needs to be further into the house than the innermost part of the aluminum frame so that the aluminum frame will be hidden after we apply the inside trim. What if you have brick around the window openings? Or siding? Then what? Well, if you can install the window against the face of the brick or siding and still have the innermost part of the vinyl frame be further into the home than the old frame, then you can use the retrofit style frame. If not, then you have to use the replacement style frame,then use trim to finish the outside. If you are able to get a retrofit frame with a relatively thin fin, you can also trim down the fins so the window fits between the brick or wood. That would eliminate the need to trim out the outside. Some manufacturers of retrofit frames will have grooves in the back of the retrofit fins. You simply run a utility knife in the groove until you are able to break off that piece of the fin.
The main point to remember when determining whether or not to use a retrofit frame or a standard replacement frame is that in order to use the retrofit frame there needs to be less than 3 inches from the outside point where the flush fin will rest to the inside point in the room where the old frame ends. If it's less than 3 inches, go with the retro, more than 3 inches, use the replacement frame and add trim to the outside in lieu of the flush fin.
Next week I am going to explain the process of removing the old aluminum window.