The research studies the day-lighting and sun-lighting of the living space of six models of houses design by architects and developers. These models were the result of a typological study of two groups of affordable medium-sized detached houses located in northwest France (225 real-estate development houses and 78 architectural competition houses with no specific client). The results show that all the models allow a satisfactory to very satisfactory level of daylight and sunlight. The differences appear in the way that the light is distributed, while the developers houses present smaller openings with several orientations resulting in a longer day-lighting autonomy, architectural competition houses offer a more heterogeneous disposition of openings with a predominance of the big mono-oriented opening that creates harsh contrasts and glare.