What Is a Sand Trap Louver? How It Keeps Wind-Driven Sand Out of HVAC Intakes
A sand trap louver keeps wind-driven sand out of HVAC intake and exhaust openings using vertical blades and a sloped sill, rather than the angled blades a standard weather louver uses for rain. Here's how it works and why it isn't a substitute for an air filter.
A sand trap louver, sometimes called a sand louver, is a weather louver built specifically to keep wind-driven sand out of air intake and exhaust openings on a building's exterior wall. Goodwind's version (model GT-STL) uses vertical sightproof blades to separate sand from the airstream, then channels it away at a sloped sill before it reaches the duct behind the opening.
How a Sand Trap Louver Works
Wind carries sand toward an intake opening mixed into the same air the building needs to draw in. The vertical blades in a sand trap louver force that airstream to change direction sharply as it passes through. Sand particles carry more inertia than air, so they don't follow the turn as easily. Rather than curving through the louver with the airstream, the sand continues on a straighter path and lands on the sloped sill built into the base of the unit. The sill is angled so the collected sand drains or blows back out, instead of building up inside the opening.
This is a different approach from a standard weather louver, which uses angled horizontal blades to block driving rain. Rain and sand behave differently in an airstream, so the blade geometry that works for one doesn't work well for the other.
Where They're Used
Sand trap louvers go on exterior wall openings in buildings exposed to blowing sand and dust, most often in desert and coastal-desert climates. As a sand trap louver manufacturer with project experience in the UAE and Bahrain, including the Dilmon Project in Dubai and Amwaj Villas in Bahrain, Goodwind builds these for sites where sand exposure is a normal condition rather than an occasional problem.
What It Doesn't Do
A sand trap louver is not a substitute for a conventional air filter. It's built to stop coarse sand and grit before that material enters the building, but fine dust and particulates still need to be filtered downstream the same way they would on any HVAC intake. Specifying one doesn't remove the need for filtration further into the system. It reduces how much bulk sand that filtration has to deal with in the first place.
Frequently Asked Questions
What is a sand trap louver?
A sand trap louver, also called a sand louver, is a weather louver designed to protect air intake and exhaust openings from wind-driven sand, using vertical blades and a sloped sill to separate sand from the airstream before it enters the building.
How does a sand trap louver separate sand from air?
The vertical blades force the airstream to change direction as it passes through. Sand particles have more inertia than air and don't follow that turn as easily, so they continue on a straighter path and land on the sloped sill instead of entering the duct.
Does a sand trap louver replace an air filter?
No. It stops coarse sand and grit at the opening, but fine dust still needs to be filtered downstream. It's designed to reduce the load on that filtration, not replace it.
Where are sand trap louvers typically used?
On exterior wall air intake and exhaust openings in buildings located in desert or coastal-desert climates, where wind-driven sand is a regular site condition.
If you're specifying intake protection for a site with wind-driven sand or dust, get in touch with your opening size and airflow requirement and we'll size a sand trap louver to it.