Every year the industry invents a new gadget that promises to make buildings green. Heat pumps, smart glass, carbon dashboards. All useful — and all secondary. The cheapest kilowatt-hour is still the one you never need, and the oldest way to avoid needing it is to design with the sun instead of against it.
Start with orientation, not equipment
On our recent Maple Row scheme, rotating the terrace just eleven degrees cut peak summer solar gain by nearly a third — no equipment, no maintenance, no moving parts. Living spaces face the morning sun, service rooms take the harsh western edge, and deep reveals shade the glass exactly when it matters. These are decisions made with a pencil in week two that outperform hardware installed in month ten.
Borrow light deeper into the plan
The average home uses artificial light in its hallway at noon. That is a design failure, not a lifestyle choice. Light shelves, borrowed-light glazing above doors, and stairwells treated as light wells can push useful daylight twice as far into a floor plate. At Casa Lumen, the central stair is a skylit spine — corridors need no daytime lighting at all.
“Design the building to sip energy first. Then — only then — size the systems for what is left.”
Materials that do double duty
Thermal mass is back, but smarter: lime plaster that buffers humidity, timber structure that stores carbon, and clay blocks that hold the day’s warmth into the evening. None of these are exotic. All of them ask the designer to think in sections, not just plans — to draw how heat and air actually move through the building.
None of this argues against modern systems. Our projects still specify heat pumps and mechanical ventilation with heat recovery where they earn their place. The point is sequence: passive measures first, efficient systems second, offsets never as an excuse. Build the shade before you buy the chiller.
Sofia Karlsson
Head of Engineering at Struvia. Fifteen years designing low-energy homes and workplaces.
