The section as relato is the drawing that reveals what a courtyard actually does. The plan locates rooms. The section explains light, privacy, air movement, and the felt experience of moving through a house built around a void. In Mexico City, where lots are sloped, densely built, and at a latitude where sun angles change dramatically between seasons, the section is not a document produced after the plan — it is designed simultaneously with it.
Mexico City Latitude and Sun Angles
Mexico City sits at 19.4 degrees north latitude. This position creates a dramatic seasonal range in sun altitude:
- Summer solstice (June): solar noon altitude approximately 87 degrees — nearly vertical
- Winter solstice (December): solar noon altitude approximately 47 degrees — noticeably lower
- Spring and fall equinox: solar noon altitude approximately 67 degrees
The practical consequence: at noon in June, the sun drops almost straight into the courtyard and shadows are minimal. In December, the same courtyard may be largely shaded if the surrounding walls are tall. Asoleamiento — the analysis of how the sun moves through the section across the year — determines whether the courtyard receives usable winter sun or sits in cold shadow from November to February.
In MÉTODO, we run section sun-angle diagrams for December 21 and June 21 at 8 am, noon, and 4 pm. These six moments are enough to determine overhang depths, wall heights, and where glazing should be placed.
The Level Change as a Sectional Instrument
Mexico City's topography is not flat. Lots in Lomas, San Ángel, Pedregal, and Tlalpan routinely carry 1-3 m of grade change across a standard 12 m depth. This is not a problem to be engineered away — it is a sectional opportunity.
A half-level drop from the entry courtyard to a lower rear patio creates:
- Visual separation between zones without full floor-to-floor height difference
- A lower private courtyard that neighbors cannot see into even without tall walls
- A section that reads as dynamic — the experience of arrival, descent, and expansion
When we work with a sloped lot, the first sectional move is to find the natural mid-point of the grade change and place the courtyard level there. Rooms step up toward the street and step down toward the rear. The courtyard becomes the datum — the fixed reference point from which all levels measure.
Privacy in a Dense Urban Section
Mexico City's residential neighborhoods are dense. Adjacent buildings are often 2-3 stories and built to the property line. A courtyard house that prioritizes sunlight will have low courtyard walls. One that prioritizes privacy from neighbors will have tall walls. The section must find the specific balance for each site.
The privacy calculation:
- At a 4 m courtyard width and 3 m wall height, a neighbor at ground level 3 m away cannot see in at a downward angle
- Adding a 1 m parapet above the neighbor's roofline blocks elevated sightlines
- Planting — a tree whose canopy sits at 3-4 m height — can screen without adding wall mass
Materialidad honesta: a concrete block wall with board-formed texture ages better than a plastered CMU that will need repainting every three years. The privacy wall is a significant surface in the section; its material matters.
The Zaguán: Compression Before the Courtyard
In Mexico City's colonial and early modern residential tradition, the zaguán — the compressed transitional passage from street to patio — is a sectional instrument as much as a plan element. In section, it appears as a lower ceiling height: 2.4-2.7 m. The courtyard it releases into rises to 5-6 m at the parapet. The compression makes the release more powerful.
Contemporary interpretations of this move work without copying the colonial vocabulary. A low entry volume — monolithic concrete or stone — that opens into a full-height courtyard achieves the same sectional effect. The ceiling height drop, the transition from solid to void, the light that arrives from above: all of this is designed in section before the plan finishes.
The Section Determines the Corridor
In a courtyard house, the corridor that runs along the courtyard edge is not simply a circulation space — it is the transitional zone between inside and outside, and its roof is the critical overhang that governs sun and rain protection. In section:
- Too shallow an overhang: summer sun penetrates the corridor and heats the rooms behind
- Too deep an overhang: winter sun is blocked, and the corridor becomes dark
- The right depth: summer sun is cut off at the mullion line; winter sun reaches 60-70% of the corridor depth
This calculation is specific to the site's latitude and the corridor's orientation. It cannot be borrowed from a precedent at a different latitude — it must be derived each time.
Próximos pasos
If you are beginning design on a Mexico City lot, the section through the courtyard should be drawn within the first week of the project — not at the end of schematic design. The decisions it encodes — overhang depths, level changes, wall heights, zaguán compression — cannot be fully corrected once the plan is fixed.
Conoce el método de MÉTODO to see how we structure the early design process around the section, not around the plan.