The condition of the opening matters more than the label on the box
Install method, flashing approach, sill condition, frame material, glazing package, trim restoration, and sun exposure on that wall count for as much as the product itself.
Build a complete scope
- Which of the city's build eras this house belongs to
- Whether original sash in the older districts is worth repairing
- Openings measured individually rather than taken from a plan
- Glazing chosen for heat gain, and how the opening is flashed for storms
- Trim restoration, removal of old units, and what the warranty covers
Columbus context
The climate points this specification away from the northern default. Humid heat makes solar heat gain through the glass the dominant comfort factor, so a low gain coefficient matters more here than an insulating value chosen for cold winters. Heavy storms rolling up the valley drive rain horizontally against elevations, which puts the weight on flashing and on the air seal achieved at the opening rather than on the unit itself. Mature canopy keeps shaded elevations damp long enough that any shortcut in that detailing shows up quickly, and rolling lots mean exposure differs sharply from one face of a house to another.