The main objective of Rain Defence Louvres is to allow the passage of air, whilst providing the area beyond the room with protection from rain penetration.
When specifying rain defence louvres we recommend comparing the airflow class and the level of rain defence provided by the louvre.
Our CS RS-5605 rain defence louvre offers the best combination of airflow, rain defence and spatial efficiency of any product on the market.
Why CS Rain Defence Louvres
- industry leading performance characteristics
- unparalleled global experience
- worldwide technical support
- first class innovation & designs
- most spatially efficient models on the market
- up to 100% rain defence with some models
- robust blades up to 3x thicker than rolled blades
- up to date, relevant test information
Louvre pressure drop is one of the key parameters of establishing the louvre requirements for your project as it’s based on the needs of the building and its ventilation system, rather than “free area” which doesn’t really mean anything.
Pressure drop is defined as the pressure differential from one side of a louvre to the opposite side, often expressed in Pascals (Pa). Louvre pressure drop occurs when frictional forces, caused by the resistance to flow, act on air moving through a louvre.
Increased louvre pressure drop can prevent equipment inside the ventilated area drawing sufficient air through the louvre, resulting in overheating, as the equipment has to work harder to draw the air through.
Guidance
Air Density (ρ)
is generally 1.225 kg/m³ (at sea level)
Volumetric Flow (qv)
is supplied by the ventilation engineer and relates to the amount of air required through the system
Core Area (A)
The minimum height times the minimum width of the front opening in a louvre assembly with the louvre blades removed.
Discharge Loss Coefficient (CD)
See chosen louvre model testing information.
Discharge Loss Guidance
Louvre Model | Penetration Class | Airflow Class | Discharge Loss Coefficient |
---|---|---|---|
RSH-5700 | A up to 3.0m/s | 3 | 0.289 |
RSV-5700 | A up to 3.5m/s | 3 | 0.297 |
RS-5605 | A up to 3.5m/s | 1 | 0.466 |
A-3105 | D up to 3.5m/s | 2 | 0.391 |
A-4080 | C up to 1.0m/s | 2 | 0.38 |
A-4085 | C up to 1.0m/s | 2 | 0.38 |