Downlights

Downlights, also known as recessed lights or downlight luminaires, are lighting fixtures installed into a ceiling so the light source is recessed above the ceiling plane. They provide a downward-directed beam, offering general, task, or accent lighting without visible fixtures.

Most downlights use a housing and a trim with a bulb or LED module. Common sizes include 4-inch and 6-inch diameter cuts. LED models are prevalent for energy efficiency, long life, and low heat; older installations used halogen or CFL lamps. Downlights can be fixed (non-tilting) or adjustable/gimbal, allowing some aiming of the beam.

Installation considerations include housing design and compatibility with ceiling structure. IC-rated housings can be in direct contact with insulation; non-IC housings require clearance. Some housings are designed for remodeling (new work) or for installation in finished ceilings (old work). Airtight housings minimize air leakage, and fire-rated ceilings may require rated assemblies to maintain fire separation.

Design and performance factors include beam angle, which affects light spread; color temperature, commonly ranging from warm 2700–3000K to neutral daylight 4000–5000K; and color rendering index, which influences how colors appear under the light. LED downlights often provide dimmable operation with compatible drivers. Proper spacing and layering with other lighting influence ambience and function.

Applications include residential and commercial settings such as kitchens, hallways, living rooms, offices, and retail spaces. Advantages of downlights include a discreet appearance, versatile placement, and energy efficiency with LEDs. Potential drawbacks can include the need for ceiling access for installation, glare control, and limited retrofitting options in some ceiling types.