Window Frame Compatibility: The Real Test for Trickle Vent Retrofits
The real decision is hidden in the frame A trickle vent retrofit looks like a simple yes-or-no question until the frame is exposed. After enough retrofit jobs, one pattern becomes obvious: the vent model matters far less than the profile it is going into. Two windows can appear almost identical from the room side and behave completely differently once a router meets the material inside. One has a generous outer chamber and empty space above the sash. Another hides a steel reinforcement bar, a sash balance, or a thermal break exactly where the slot needs to go. ...