Understanding retrofit vs. new construction windows helps you make sense of quotes and choose the right approach for your home. The two types aren’t about how new the window is. They describe how the window is built to attach to your house, which affects cost, disruption, and how well the window is sealed against weather. Here’s what to know before you order made-to-measure replacement windows.
What Are New Construction Windows?
New construction windows have a nailing flange, often called a nail fin, around the outside of the frame. The installer nails this flange directly to the wall sheathing, then integrates it with flashing and the home’s weather barrier before the siding goes back on.
Because they attach to the wall structure itself, new construction windows require access to the framing around the opening. In an existing home, that means removing the siding, stucco, or trim around each window, which adds labor and patching costs.
What Are Retrofit Windows?
Retrofit windows are designed to go into an existing opening without removing the exterior wall finish. There are a few common types:
- Insert or pocket windows: A complete window that fits inside the existing window frame after the old sashes are removed.
- Flush-fin windows: Also called Z-bar retrofit windows, these have a flange that sits against the face of the exterior wall and covers the edge of the old frame. They’re common on stucco homes.
- Block frame windows: Windows with no flange that fit into an existing opening, often used in brick or masonry walls.
Comparing the Two
Disruption and Cost
Retrofit windows are usually faster and less expensive to install because the exterior finish stays in place. New construction windows cost more to install in an existing home because of the siding or stucco work involved.
Weatherproofing
New construction windows offer the best opportunity to integrate the window with flashing and the weather barrier, which provides strong long-term protection against leaks. Retrofit windows rely more on sealants and the condition of the existing frame and flashing.
Glass Area
Insert windows sit inside the old frame, so they slightly reduce the visible glass area. Flush-fin and new construction windows typically preserve more of the original opening.
Repairs
During a professional window installation with new construction windows, removing the old frame and siding lets the installer find and fix hidden rot or water damage. With retrofit windows, those problems can remain out of sight.
When to Choose Each Type
New construction windows usually make sense when:
- You’re already replacing siding or stucco
- The existing frames are rotted or water damaged
- You want to change the size or shape of the opening
Retrofit windows usually make sense when:
- The existing frames are sound and dry
- You want to avoid damaging stucco, brick, or newer siding
- Budget and a faster installation are priorities
Installation Quality Matters Either Way
Both types depend on careful installation. The window must be set square, sealed properly, and installed according to the manufacturer’s instructions. ENERGY STAR installation guidance notes that certified windows come with installation instructions, and some manufacturers void the warranty if those instructions aren’t followed. An experienced installer will inspect your openings first and recommend the type that fits your home’s exterior and condition.
Choosing Between Retrofit vs. New Construction Windows
The right choice between retrofit vs. new construction windows depends on your exterior finish, the condition of your frames, and your budget. Ask the company handling your window replacement services which type they’re quoting and why, so you can compare estimates accurately.
Not sure which type your home needs? Call Murray Window Replacement at (385) 786-6447 or request a window replacement estimate to have your windows inspected.