What Is a Double Louver Grille? Specs and How to Specify One
A double louver grille uses two rows of angled blades for extra airflow direction control and a deeper sightline block. Specs, applications, and how to specify one.
A double louver grille is an HVAC air terminal with two rows of angled blades set front-to-back, giving more control over airflow direction and a deeper visual block than a single-louver grille. Goodwind manufactures the Double Louver Grille (model G-DD) in aluminum, steel, or custom material, for commercial, residential, and industrial projects.
Double Louver Grille Specifications
| Spec | Detail |
|---|---|
| Model | G-DD |
| Material | Aluminum, steel, or custom |
| Finish | Powder coated, anodized, or custom colors |
| Mounting | Wall, ceiling, duct, or floor |
| Applications | Commercial, residential, industrial |
Where Double Louver Grilles Are Used
The second row of blades gives a double louver grille a tighter sightline than a single-row grille, so it's a common choice where the opening needs to block direct view into the duct or space behind it — return air openings near sightlines, or locations where a single louver row leaves too clear a view through. The trade-off is a lower free area than a single-louver or eggcrate grille of the same face size.
How to Specify a Double Louver Grille
For MEP Consultants at the Design Stage
Specify a double louver grille where sightline blocking matters more than maximum airflow, and confirm the required free area against the opening's airflow duty, since the second blade row reduces open area compared to a single-louver design. Where airflow is the priority and sightline isn't a concern, a single-louver or eggcrate grille will generally pass more air for the same face size.
For Contractors at Procurement Stage
Confirm the mounting method and finish against the drawing before ordering, since the grille is manufactured to the specified size rather than stocked in fixed dimensions. Double-check that the drawing actually calls for double louver and not a standard single-row grille, since the two can be confused at spec-reading stage.
FAQ
What is a double louver grille used for?
It's used where the opening needs a tighter sightline block than a single louver row provides, commonly on return air openings near visible areas.
Does a double louver grille pass less air than a single louver grille?
Generally yes, since the second row of blades reduces the free area compared to a single-louver grille of the same face size.
Can double louver grilles be custom sized and finished?
Yes. They're manufactured in a range of sizes and finishes, including powder coating and anodizing, to match project requirements.
What materials are double louver grilles made from?
Aluminum, steel, or custom material.
Need a tighter sightline block on a visible opening? Contact Goodwind for technical input, or see our decorative grille guide for another appearance-focused option.