Can 70 mph winds break windows?
Sarah Richards
Published May 23, 2026
A Design Pressure or DP rating measures the strength of a window. Standard residential windows have DP values between 15 and 50. A DP 15 window can reasonably be expected to sustain winds of roughly 77 mph before shattering. A DP 50 window is expected to sustain winds up to 173 mph.