Site/Context

The site is part of the new west zone of Ahmedabad in an area that is dotted with very large homes on vast tracts of land. Ad-measuring about 1500 sq. yards, the site was accessible from both the east and west, lending itself to an interesting connect with its edges.

Program
The house was designed for a working couple, a teenaged daughter and her grandparents. The brief required us to provide a 4 bedroom dwelling with a central dining and living space with connects to the verdant outdoors. The clients were eager to explore the use of lime as a building material along with some simple initiatives for achieving thermal comfort.

Architectural response and climate
The site is part of a developing zone and hence prone to flooding. A raised plinth became mandatory and in a way helped define the scale in relation to the edges.

A building language that is expressive of our concerns to be sustainable was our main objective.

The gradual breaking up of the mass allows the roof top water to find its way to the large metal gargoyle on the west, which leads water to the channel and eventually to the rain-water harvesting tank. This orchestration along with the use of lime- plastered walls defines the intent.

The built form, comprises, confined masonry walls sitting on a raised plinth, oriented to keep the sun at bay and allowing for natural breezes to flow within the building.

The house is aligned north – south on its longer axis owing to the dimensions and the orientation of the site. The east and west facades are protected by a bamboo trellis structure meant to grow creepers and vegetables on vines, and provide the necessary shade. In addition, the service spaces- toilets, utilities, staircase etc., located on the south and west help insulate the living areas further.

The quasi- courtyard formed by manipulating the massing on the west creates a thermal barrier between the dining block and the open west garden. The inner spaces tie into this volume visually, providing an interesting play of light during the day.

The verandah on the west and the small patio opening to the pond and deck on the eastern edge, provide the opportunity to use the spaces and enjoy mornings and evenings with comfortable ventilation.

Large sets of doors coupled with wooden louvers help control the light and cut out glare.

The prevailing breezes are channeled into the home through a vertical shaft over the puja space that works like a stack to flush the inside spaces with night-time cool air. A ceiling fan placed in the shaft provides the draft required to create the necessary air changes.

Materials/details/ thermal strategies.

The strategy for thermal comfort was to use materials that would be naturally emissive. Lime and surkhi bricks, lime mortar and lime plaster on the exterior and dolomite plaster in the interior was the material chosen for the dwelling.

RCC confined columns in masonry and slabs were engineered for economy and strength. The exterior flooring comprises various sizes of brown kotah stone while the interior spaces us natural marble. All wood used is recycled from old structures in and around Ahmedabad.

The use of terracotta lime plastered walls with natural mineral pigments, contrasts with the lightness of the steel and bamboo trellis structures for shading, become expressive of our larger concerns. The roof is insulated using nodules of Light Expanded Clay Aggregate- mixed with aerated cement. The surface is then finished with white china mosaic for added thermal reflectivity.

Interior surface temperature readings taken with an infrared thermometer post completion give a stable and consistent reduction in temperature by about 10 deg.c during the summer months. Hi-wall air conditioners set at 29 deg.c are used only as dehumidifiers when the levels become unbearable.

(Client name not divulged on request to respect their privacy)