Installing Replacement Windows in a Stucco Home

A commonly used building material, particularly in warmer climates, stucco provides a distinctive look to a home. While it has definite advantages — for example, it’s rigid and pest-resistant — it is also fairly brittle and cracks easily. That makes replacing windows in a stucco home a process that requires a specific technique to avoid damaging it.

One tried-and-true method of window replacement in a stucco wall is called “flush fin,” sometimes referred to as “stucco flange” or “jump frame.” This technique fits the new window over the existing frame to prevent the risk of damaging the stucco or the interior drywall in the removal and reinstallation process.

Flush Fin Window Replacement, Step-by-Step

Homeowners with stucco exteriors can improve the appearance of their residences and reduce their energy bills through flush fin replacement windows like the Andersen 100 Series. This frame option has an integrated “fin” around it that allows for installation directly over an existing aluminum frame without the need to remove it first. This fin covers the old frame completely and overlaps the stucco to create a smooth exterior appearance. Professional installation ensures there is no damage to the structure in the process.  

At a high level, the replacement process looks like this:

• First, carefully remove the existing sash and prepare the rough opening. Position the new window in the opening and see if the flange needs to be trimmed. This can be done right on site.
• Thoroughly clean the existing window frame and the inside of the flange of the replacement window in order to ensure good contact.
• Position shims on the sill and apply sealant to the existing frame, but leave gaps for water drainage. 
• Place the new window in the opening and attach it, checking that it’s plumb, level and square before completely tightening all the fasteners.
• Inside the home, apply an air seal around the assembly and add the interior trim. Outside, add a bead of sealant, again with gaps at the sill for water runoff.

Alternatives to Aluminum Framing

The aluminum window frames that are often used in stucco homes may not provide sufficient energy efficiency or indoor air quality. They conduct a lot of heat, which can be a real problem in the warm climates where most stucco construction occurs. Furthermore, aluminum is subject to corrosion, requiring maintenance to keep it clean and attractive.

Fibrex®, the material used in Andersen’s 100 Series flush fin windows, is a unique combination of reclaimed wood fiber and thermoplastic polymer, which is also partially reclaimed. It blocks heat transfer almost 700 times better than aluminum; retains its stability in any climate; and resists flaking, blistering and peeling at temperatures up to 150° F. It doesn’t require painting because the color is incorporated into the assembly during production. In other words, Fibrex is a material ideally suited to the warm climate in which most stucco homes are located, and when combined with the right glass, provides a durable, energy-efficient and attractive replacement for existing aluminum-frame windows.

The Flush Fin Advantage

Window replacements in stucco homes don’t have to come with the risk of creating expensive exterior damage. The flush fin installation process utilizes the existing aluminum frame by covering it over with a more durable, attractive and better-insulated window that will last for a very long time.

For more information, visit andersenwindows.com.