In the historic center of Premià de Dalt, Barcelona-based practices LABLANCA and Santa Arquitectura renovated the upper floor of a narrow row house by cutting a single roof opening where its two roof pitches meet.The 1,450-square-foot (85 sqm + 48 sqm) house had absorbed decades of modifications and now sits split horizontally into two separate properties, leaving the architects only the top floor to work with. Rather than fighting the narrow-and-deep footprint typical of this house type, the project treats the resulting darkness as the problem the entire design exists to solve.
Section, not plan, drives every decision here. Row houses like this one share the same built-in constraints — narrow width, considerable depth, and light that struggles to reach the middle of the house. LABLANCA and Santa Arquitectura read those constraints as a section problem rather than a layout problem, organizing the common rooms along the main volume and pushing private rooms into a rear annex, with the void between floors doing the real spatial work.
A single skylight carries most of the project’s ambition. At the junction where the two roof pitches converge, a roof opening cuts directly into that seam, pulling daylight down into the center of the main volume — precisely the zone a narrow row house typically struggles to light at all. Light-toned wall surfaces throughout help that daylight travel further than a single opening should reasonably allow, spreading it rather than letting it pool directly beneath the cut.
Cross ventilation follows the same opening. The new aperture beneath the roof doesn’t just admit light — it opens the house to airflow and to the exterior at the same time, turning a single architectural gesture into three separate functions instead of treating light, air, and outdoor connection as problems requiring three separate solutions.
Even the bathroom gets its own skylight. Built as an independent volume within the main body of the house, the bathroom incorporates a rooflight that connects visually back to the main volume, letting daylight reach a room that would otherwise have none and reinforcing the sense that no space in the house was designed to be cut off from the rest.
The old attic becomes the project’s second major move. LABLANCA and Santa Arquitectura opened up the former loft space beneath the roof, converting it into an open mezzanine that functions as a transitional zone between interior and exterior. The gesture extends sightlines through the house and claims the full available height — space a conventional attic conversion would have simply enclosed.
Void, not square footage, is the material actually being spent here. The renovation’s real currency isn’t the 133 square meters combined across both floor areas — it’s the volume deliberately left empty at the roof junction and above the old attic, unbuilt space doing more spatial work than any additional room could have done in its place.
The same principle drives our own reporting on attic daylighting — treating a skylight as a main window rather than a supplement, since in a converted roof space it is frequently the entire daylight budget rather than a bonus on top of vertical glazing. Our guide to bringing natural light into a loft covers this exact logic in more technical detail, from light tubes to borrowed light through interior partitions — tools that become necessary once a house commits, as Ca la Tere does, to a single roof opening as its main daylight source.
A comparable commitment to compression and light as the real design tools inside a constrained shell drives Iterare Arquitectos’ Casa Nido in Valencia, where a narrow limestone stair core compresses before releasing into a skylit room upstairs, circulating light in through one major opening rather than several smaller ones. Both projects treat a single carefully placed void as more valuable than any amount of added floor area.
The claim worth testing here is a narrow one: that one well-placed roof opening can do the work that a full-height addition or a wall of glazing usually gets asked to do in a row house this constrained. Whether that holds depends entirely on how much daylight actually reaches the ground-floor rooms furthest from the skylight — a question the section drawings answer more convincingly than any photograph of the opening itself can.
Ca la Tere by LABLANCA and Santa Arquitectura | Location: Premià de Dalt, Spain — Year: 2025 — Key materials: not confirmed in source material — light-toned interior surfaces and skylight glazing referenced only