Think of your building like a dartboard. The bullseye (center) gets light pressure, but the edges? That is where wind goes crazy. Click the building to see exactly where you need the strongest windows.
Like a weather map for your building. Red zones need the toughest windows, blue zones can use standard options.
Enter your project details to see exact pressure requirements for each zone.
* Negative values indicate suction (outward). Positive pressure on windward face adds to total design pressure.
In every hurricane, corner windows break before center windows. Why? Because they face 3x more wind pressure. One wrong window in a corner can blow out your entire envelope.
Zone 1 windows need less strength than Zone 5. Smart contractors use premium windows only where needed and save money on interior positions. Same protection, lower cost.
Inspectors check that corner windows meet Zone 5 requirements. Many projects fail because the contractor used Zone 1 windows everywhere. Know your zones, pass your inspection.
Think of them like a heat map showing where wind pressure is strongest. Zones divide your building into areas based on how hard wind pushes (or pulls). Zone 5 at the corners gets hit hardest - about 3 times harder than Zone 1 in the center. Each zone needs windows and doors rated for that specific pressure.
Imagine water flowing around a rock in a stream - it speeds up as it wraps around the edges. Wind does the same thing at building corners. As it wraps around, it accelerates and creates intense suction. This "corner effect" is why Zone 5 corners need windows rated for much higher pressures than the middle of the wall.
Zone boundaries depend on your building size. Engineers calculate a distance called "a" (usually about 10% of your building width, minimum 3 feet). If a window is within that distance from BOTH edges, it is Zone 5. Within that distance from ONE edge, it is Zone 4. Everything else in the middle is typically Zone 1. Our PE analysis shows exactly which zone each opening falls into.
Yes, if you choose windows rated for Zone 5 everywhere - but that costs more. The smart approach is using Zone 5 windows only in corners, Zone 4 along edges, and Zone 1 in the center. You get the same protection at lower cost. Our analysis tells you exactly what each location needs.
PE-stamped analysis showing exact zones for every window and door on your project. Stop guessing, start knowing.
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