Window casing finishes the joint between the window opening and the interior wall. It can be damaged even when the window itself works correctly, which is why trim should be treated separately from window replacement.
Common Casing and Trim Problems
Issues may include loose casing, open joints, damaged corners, split material, trim removed during another project, or a profile that no longer meets new wall or window finishes cleanly.
Moisture staining or soft trim may indicate a problem beyond the casing.
Repair or Replace?
A localized section may be repairable when the profile and surrounding material can be matched.
Replacement may be more practical when several pieces are damaged, the old profile is unavailable, or the opening has been changed.
New Installation and Replacement
Casing needs to relate to the jamb, wall plane, sill, stool if present, baseboard, nearby trim, and the desired reveal around the opening.
Profiles and dimensions should be selected as part of the room finish rather than in isolation.
Installation Process
The opening is measured, old material is removed as needed, and new pieces are cut to the actual angles and dimensions.
Small wall gaps or jamb differences may affect fit, but broad drywall or window-frame repair should be scoped separately.
FAQ
Can only one casing piece be replaced?
Often, if the profile and finish can be matched.
Does casing repair fix window leaks?
No. Trim is not a substitute for solving water entry or a failed window.
Can trim be changed during window replacement?
Yes, but window installation and trim finishing should be coordinated as separate components of the project.
Is painting included?
Finish work should be confirmed separately.
For frame damage, see Window Frame Repair or use the contact page.