A dwelling's orientation determines its brightness, thermal comfort and energy consumption. Here are the principles to know before choosing a plot.
Even before thinking about the materials or surface area of a dwelling, the orientation of the plot is the first architectural decision, and often the one that most determines everyday comfort.
Understanding the subject
In mainland France, a general south-facing orientation remains the reference: it maximises natural light in winter, when the sun is low, while limiting summer overheating if roof overhangs or sunshades are properly sized. A main façade facing south or south-west also makes the most of late-afternoon light, which is particularly sought after for living spaces.
An east-west orientation has its own qualities: soft morning light on the east side, ideal for a bedroom, and a longer end of day on the west side for a terrace. On the other hand, it requires particular attention to solar protection in summer, as the low sun at the end of the day can cause significant glare through large glazed openings.
Going further
Beyond the points of the compass, topography matters just as much: a gentle south-facing slope naturally receives more sun than a flat plot hemmed in by hills or dense vegetation. Solar obstructions (neighbouring buildings, mature trees, ridgelines) should be studied at different times of day and in different seasons, not only at the time of the site visit.
Practical advice
Finally, the region's prevailing wind influences where openings and outdoor spaces are placed: a terrace sheltered from the prevailing wind will be used far more often than an exposed one, even if it is perfectly oriented towards the sun.
These principles, although universal, apply differently to each plot. This is why a personalised siting study remains the best way to turn a plot into a living project that is genuinely suited to you; this is notably what we offer on request for every AIIA modular home.
An architectural perspective
Frequently asked questions
What is the best orientation for a compact dwelling?
There is no universally "best" orientation: south maximises winter light, while east-west offers different light in the morning and evening. The right choice depends on the land, the local climate and the intended use of each room.
Can a poor orientation be corrected after construction?
Only partially: sunshades, vegetation or external blinds can mitigate certain excesses, but the amount of natural light a façade receives remains largely fixed at the design stage.
