Retrofit or Full Frame Window Replacement for Stucco Homes

Two windows that look identical from the street can be installed in completely different ways, one set inside the old frame and one set into the bare rough opening. On stucco homes in San Bernardino, CA, that choice decides how much wall gets cut open, as the notes at window installers san bernardino cowboy santas describe. The sections below follow the job in the order it happens.

Retrofit or full frame

A retrofit, also called an insert, fits the new window inside the existing frame, so the surrounding stucco stays untouched. The tradeoff is small. The new frame sits inside the old one, so the visible glass area drops slightly. On a sound frame, a well set retrofit is a proper install. A full frame replacement strips the old window down to the rough opening. That exposes the framing, and installers can probe the sill and jambs for hidden water damage before anything new goes in.

Fin styles and the stucco

Flush fin retrofit windows have an exterior lip that covers the old frame edge. That lip gets sealed against the stucco surface. New construction windows with nailing fins usually mean removing a strip of stucco around the opening, nailing the fin to the framing, and patching afterward. A patch that is floated and textured with care can blend into the wall. Older homes in Muscoy and Loma Linda often have aluminum window frames set tight in the stucco, and those need the most careful cutting.

Setting the unit

Shims set the window level, plumb and square. Check the diagonals with a tape before fastening anything. A frame that is even slightly out of square makes a double hung ride crooked in its tracks, makes a slider drag, and makes a casement sash miss its seal on one corner. Shim at the hinge points and the lock points so the seals compress evenly all the way around.

Flashing and sealant

Flashing is lapped like shingles. Upper layers overlap lower layers, so water travels outward and down instead of behind the wall. The sill goes first, then the jambs, then the head. Caulk alone does not keep water out of a wall. It is a secondary seal over flashing that is already shedding water correctly. A bead of sealant on a poorly lapped opening only delays the leak.

Foam and final checks

Use low expansion foam around the frame. High expansion foam can bow a frame inward, and then the sashes bind. A bowed vinyl window is the common case, and the stress can also reach the seals on insulated glass, so a double pane unit may fog later. Foam gently, let it cure, then trim the excess. Open and close every sash, check the locks, and run a bead of sealant only where the flashing plan calls for it. Interior trim goes on last, once the unit operates freely.