What are the retrofit downlights? What does it feature? The Retrofit Recessed Lights are a type of downlight, that retains the existing above-ceiling fixture and lighting layout, upgrading the lamp source. Retrofit Recessed Lighting Fixture Type: Round, Square, Baffle, Flush. It is easy to retrofit halogen bulbs to recessed lighting. Recessed lighting retrofit uses advanced LED technology, saves more energy, and reduces carbon emissions. Easy to install and price cheap. Recessed lighting can add 1% – 5% to your house's value. What size LED recessed lights should I use? To fit your ceiling size. 3‘’ and 4'' retrofit recessed lights are suitable for lighting small areas or as supplementary lighting. 6'' light fixtures are usually used for general lighting purposes. Above 10'' lights, creating a wider lighting. The size of 4'' and 6'' are the most popular. How many recessed lights per square foot? It is about every 4 to 6 square feet of ceiling space. How far apart should recessed lights be spaced? The half of the ceiling's total height.