The Urban Solarium project addresses the issue of energy efficiency through the lens of thermal performance in the context of urban housing. Located in the historic brick row house neighborhood of Boston's South End, the project utilizes brick for its inherent property of high heat capacity – a material's ability to store radiant energy and release it later due to the temperature difference between day and night – as a thermal battery for heating and cooling domestic spaces.
In Boston where the temperature frequently goes below freezing in winter time, the project challenges existing housing typologies by incorporating thermal mass as a passive solar strategy at the scale of an entire structure. The urban solarium produces an interstitial zone in housing that promotes a new lifestyle by bringing together thermal performance and urban farming.
(TOP) During summer time, the solar room protects the thermal mass wall from overheating with its deep overhang. In winter time, the low sun angle penetrates the solar room and provides direct solar gain on the masonry wall.
(BOTTOM) On the southwest facade of the corner lot, the project has year-round direct solar exposure. While the southwest corner of the project is occasionally blocked by shadows casted from adjacent building in summer mornings and winter afternoons.
Urban Solarium is a layering of systems. The solar rooms are protected with large sliding doors that remain open in the summer to promote air circulation and to prevent overheating. During winter time, the sliders will be closed to create a greenhouse scenario for raising room air temperature using passive solar strategy.
The masonry wall is rotated 45 degrees for direct southern exposure and pleated to increase surface area. It absorbs radiant energy during daytime and releases it later due to diurnal swing. In winter evenings, the solar room provides both radiant and convection heat delivered into the living space through operable vents.
The project is set up as a series of zones providing different levels of thermal comfort: the solar room, circulation zone, and living spaces. The solar rooms are programmed as urban gardens and shaped according to sunlight and shadow studies. Varying depths of planting trays at each level allow vegetation with different root depths to flourish.