Steel Reinforced Vinyl Frames
Advanced Windows sets itself apart from other manufacturers by providing the strongest frame possible to ensure your windows won’t warp over time.
Each sash is reinforced with galvanized steel in the top and bottom rail. You can see these reinforcements in the photo (painted red for clarity)
Further, the mainframe sill is also reinforced with steel to prevent buckling.
You can finally get a worry-free double hung when you choose Advanced.