Short answer: The wind-resistance class for a European outdoor blind — Class 0 to 6 per EN 13561 — indicates the nominal and safety wind pressures the product withstood in a lab test. This class is not an inherent property; it was determined at a specific tested width and decreases as the opening widens. To interpret the rating correctly, you must ask two questions that brochures rarely address: At what width was this class achieved, and does that match the width you are purchasing?
What 13561 actually is
EN 13561 (External blinds — performance requirements including safety) is the European standard for outdoor blinds and awnings sold in the EU. It serves as the basis for CE marking of these products, with wind resistance being the mandatory performance requirement.
Wind resistance is tested against a separate standard, EN 1932. This test applies a defined loading sequence to the blind and then verifies three criteria in order: appearance (no permanent damage), operation (functional performance), and safety (no hazardous failure). The final class rating is assigned based on the results.
Official Class Schedule (EN 13561:2015, EN 1932 registration)
| Wind class | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|---|
| Nominal wind pressure pN (N/m²) | < 40 | 40 | 70 | 110 | 170 | 270 | 400 |
| Safety wind pressure pS (N/m²) | < 48 | 48 | 84 | 132 | 204 | 234 | 480 |
Two pressures are specified because they have different meanings in practice:
- pN — nominal pressureThis is the wind speed level at which the blind is designed to remain safe during normal operation. The manufacturer's instructions will specify that the blind must be retracted when wind speeds exceed those corresponding to its class rating.
- pS — safety pressureIt is the higher-level requirement that blind mechanisms must fail safely—ensuring no parts are released and posing no hazard to people below—rather than necessarily remaining functional.
Key insight most buyers overlook: class depends on width
The class is achieved at a specific tested width. EN 1932 testing is performed on a defined sample, and the loads on a wider blind increase with its surface area. However, the mechanical resistance of the tube, motor, and fabric edge retention does not scale proportionally.
Practical implication: A Class 4 rating on a 2-metre-inch screen tells you almost nothing about the 6-metre-inch screen you're actually buying. A supplier that honestly quotes the class for your actual width is giving you useful information; one that applies a single catalogue class across an entire size range is typically quoting their smallest tested unit.
What actually supports the load in a zip screen?
When reviewing a test report, it's helpful to identify which components the test actually exercises:
- Edge retention system.A zip screen's fabric runs within enclosed side tracks, secured by a welded or extruded bead. Under wind load, the fabric tends to lift out of the track—the bead-and-track geometry resists this force. This is the key distinction between a zip screen and a roll-down blind, which is why they are not considered in the same wind-load category.
- Bottom bar and tensioning.The bottom profile adds mass and rigidity; insufficient tension causes the fabric to flutter, increasing load on the entire assembly.
- Tube, motor, and brackets.The winding tube must not visibly deflect, the motor must hold the load in position, and the brackets transfer all forces to the building. For larger widths, the tube diameter and wall thickness differ between "domestic" and "commercial" versions of otherwise identical screens.
- The fabric.Mesh and PVC-coated fabrics exhibit different stretch and tear behaviors. A test class is determined by a specific fabric; changing the fabric grade may alter the result.
Four questions to ask before comparing quotes
- At what width was this class achieved?— The question that separates real data from brochure claims. Ask it about the specific opening you're buying.
- Is this quote for a custom-engineered unit at my width, or is it for the standard production model?— Larger openings may require a heavier tube, a more powerful motor, or additional intermediate brackets.
- At what wind speed does retraction occur, and is a wind sensor included?— The class is only meaningful if the control system acts on it. Retract-above thresholds must be documented in the technical manual, not improvised on-site.
- What happens above the safety pressure?The correct answer is: "The fabric may detach from the tracks without the assembly losing parts or falling," not: "Nothing—it's rated for everything."
Frequently asked questions
Does a higher wind rating mean I never need to retract the screen?
No. Every retractable outdoor blind has a maximum wind speed above which it must be retracted, as specified by the manufacturer for its class. A higher class raises this threshold but does not eliminate it entirely. Fixed louver systems—not retractable screens—are the products that remove the need for retraction altogether.
Is EN 13561 required?
For outdoor blinds and awnings sold in the EU, CE marking is standard. In practice, a compliant product should display the mark along with supporting documentation. Outside the EU, it is voluntary but widely used as the reference basis for wind ratings.
Can I convert wind pressure in N/m² to wind speed manually?
Pressure and speed are related, but conversion depends on air density, which varies with altitude and temperature. A qualified supplier should provide both the pressure class and the equivalent retraction wind speed from the manufacturer's technical data. If they cannot, treat this as a red flag.
What should a test report include?
A summary stating the standard (EN 13561 / EN 1932), tested sample width, fabric and component specifications, and the resulting class with pN and pS values. If any field is missing, the report is incomplete.
Written by the engineering team at GRAND HOMEDECOR (Guangdong Grand Homedecor Technology Co., Ltd.). Class values in the table above are quoted from EN 13561:2015 Table 1, as published by CEN. If project wind loads or test reports are required, our engineering team will verify the applicable class against your opening dimensions before providing a quote.