Facade Orientation Sun Brazil Calculator

Façade orientation under the Brazilian sun (N/S/E/W)

Because the sun tracks across the northern sky for most of the year in the Southern Hemisphere, in Brazil it's the north façade that catches direct sun through winter (the peak is around the June solstice, with the sun at roughly 43° altitude at noon in São Paulo). The south façade, on the other hand, stays in shade almost all year, which makes it a good spot for studios, libraries, pantries and server rooms that want a steady temperature. The east façade gets soft morning light, while the west façade takes the worst of the afternoon heat and is best given over to service areas, garages, or shaded with brises.

Applications

It comes up in bioclimatic design, passive solar layouts, and when meeting NBR 15220 (thermal performance) and NBR 15575 (the housing performance standard). The same logic shapes where you put windows, how big the brise-soleil needs to be, what tilt the PV panels get, and which rooms land on each face. A common Brazilian rule of thumb puts bedrooms east, social areas north, service to the west and the study south.

FAQ

Does this apply north of the equator in Brazil? Above about 5°S (Boa Vista, parts of Amazonas) the sun crosses both north and south during the year, so the rule loses its grip and you're better off with a sun-path diagram.

Is the west face really worse than east? It is. By the afternoon the air outside is already warm, so the same amount of radiation pushes the indoor peak higher.

And PV panels? In Brazil, point them at true north and set the tilt close to your local latitude.