Reliabilt-window-mull-kit-instructions -

: Apply additional silicone sealant to the top and bottom of the mull joint, filling any voids. If your kit includes a drip cap or mull bridge , install and seal these over the top and bottom exterior joints. Helpful Resources

: For a visual walkthrough, check out this guide on How to Mull Two Vinyl Windows Together . Window mullion installation #Lowes reliabilt-window-mull-kit-instructions

: If your windows have nailing fins or J-channels on the sides being mulled, remove them using pliers or a utility knife to allow the frames to sit tightly together. : Apply additional silicone sealant to the top

: You can find series-specific PDFs (e.g., Series 105 or 150) on the ReliaBilt Installation Support page . Window mullion installation #Lowes : If your windows

: Run a continuous bead of 100% silicone sealant along the entire length of the channel where the windows will connect. This step is critical for preventing air and water leaks.

: Lay the windows side-by-side on a flat surface. Use a utility knife to trim any excess vinyl "welds" or protruding edges from the corners where the windows will meet to ensure a flush fit.