Sash replacement and full-frame replacement are both legitimate restoration paths. The mistake is treating one as the default. The correct choice depends on the documented condition of the window system — specifically, the condition of the frame.
Sash replacement
The sash is the moving, glazed portion of the window. When the surrounding frame is sound but the sash or its glazing has failed — fogging, a broken seal — replacing the sash can be the correct, less-invasive path.
Full-frame replacement
When the frame itself is compromised, or the issues can't be resolved within the existing unit, full-frame replacement addresses the entire window. It's more involved and interacts with surrounding exterior materials, so it's reserved for situations the findings actually support.
How RADIO decides
- Identify the exact system and confirm sash compatibility.
- Document the visible condition of the frame and the sash.
- Match the path to the findings — not to a template.
- Explain the recommendation in the documented plan.