‘More light in the home’ was the advice that architects heard from all sides from the 1920s. The familiar gloom of most interiors was to make way for abundant, indirect light. Indirect light was especially popular with architects because it did not create shadows. Brinkman & Van der Vlugt also wholeheartedly embraced this idea. They worked together with Gispen, who had a large range of lamps with specially developed GISO glass, which ensured diffuse lighting. In his series of Giso lamps of the 1930s, Gispen placed the emphasis on the quality of the light produced: the milky glass reduced glare and created a diffuse, overall light.
A novelty in Sonneveld House was the lighting in the sitting room and library. No fewer than twenty-two Philinea lamps, each measuring fifty centimetres, were attached to the ceiling. They resemble fluorescent tubes and produce bright even light without shadows that is warmer than fluorescent lighting. This is because they are, in fact, normal light bulbs with an extremely long filament rather than gas-discharge lamps like fluorescent tubes.
Because Philinea lamps are still available in various lengths and colours it was not difficult to replace them during the reconstruction of 2001. Experiments with fluorescent tubes are almost as old as ordinary light bulbs: the first fluorescent lights for domestic interiors were launched in 1937.