LOCATION Alibaug is a district located 3 hours from downtown Mumbai (50min by ferry/20 min by speed boat). Formerly an agricultural and fishing zone, its proximity to Mumbai has seen it slated for phased redevelopment to alleviate the congestion of the island city. The plot for the house is nearly at the top of a hill overlooking the Arabian Sea and the skyline of Mumbai to the west.
CLIMATE Tropical, characterized by high temperatures in the summer (up to 38 degrees), mild winters (min 12 degrees), and very heavy monsoon showers (prevailing wind and rain is primarily from the west and south-west).
HOUSE 1 Perched at the highest point on the plot, with negligible protection from the western and southern sun and from the heavy rains that are propelled by strong south-westerly winds, this house has been developed as a network of volumes and courtyards with large sweeping overhangs and deep recessed verandahs. It enjoys panoramic views of the Arabian Sea and the valley.
HOUSE 2 After construction began, the client commissioned a second home with a similar program and in close proximity to the first home, allowing them, when completed, to function independently or as a single entity.
This raised 3 major issues;
a) To locate the house in such a way that it worked cohesively with house 1 without interrupting its views of the sea and valley, while positioning itself to enjoy those same views. b) To find a way to minimize the visual footprint and mass of a house with significant area requirements. c) The distinct vocabulary of the first house could not be continued into the second one as it was developed specifically for an apex location. A second identifiable language meant running the risk of a establishing a chaotic dialogue across the site, and, in the process, diluting the significance of the individual as well as the collective.
Further down the hill from house 1, along the winding access way, the former owner of the site had begun work on a home that was never completed.
This structure was now dilapidated and beyond salvage, but its location and levels seemed to provide us with some answers. The house was located at a point close to the site boundary and had been raised to an extent where it sat atop and behind a massive retaining wall along which the main access road was located. Structural analysis of the retaining wall revealed that the levels of retention were far less than the scale of the wall suggested due to a constructed basement floor, and that by adapting the existing levels, we could use the existing footprint to develop a 2-level space that stayed clear of the critical view angles of the first house. A roof garden would notionally extend the grass berm that began at the lower level of house 1 and reached the access road, the idea being to visually create a contiguous landscaped surface that began at house 1 and swept over the roof of house 2, visually reducing the latter to a continuous, horizontal stone ‘veil’ and a large roof garden beyond which the valley and the Arabian sea are visible.
The space has been planned as a variant of the ‘C’- shaped courtyard house , modified to incorporate the journey from the top of the hill ( house 1) to edge of the cliff ( the point where house 2 terminates at the retaining wall). The centrally located and tapered primary garden/pool court permeates backwards and sideways through the subterranean regions of the house, while its wide front panoramically opens onto the ‘cliff’, where a large pool overlooks a bamboo grove and the valley, its knife edge merging the foreground of the pool with the background of the Arabian Sea.
This courtyard branches inwards to form smaller courts which bring light into spaces burrowed deeper in from the periphery and allow the south-west breezes to flow through the house. These punctuated voids are expressed at the roof garden level as canyons of light that perforate the space at night.
The best views of the sea lie towards the south-west, which is unfortunately where the sun is the harshest and from where the monsoon winds bring heavy tropical rain.
Deep verandahs and shaded spaces are an intrinsic part of tropical architecture, but instead of adhering to a rigid arrangement of semi-outdoor spaces, we have allowed them to develop organically, either laterally or longitudinally alongside living and sleeping areas, based on the orientations and courtyard interfaces. This network of verandahs and courtyards forms a labyrinth of spaces and voids organized around a concrete enveloped rift in the earth, a fissure that binds the sunken courtyard to the roof garden and emerges as a concrete fragment from the roof garden. The major structural shear walls that bind this fissure are raked to maximize exposure to the north-east morning sun and to reduce direct incidence and glare from the harsher afternoon sun.
Major living spaces are located at the entry level while sleeping areas are organized around the pool and garden at the lower level. The labyrinth enables multiple journeys through the house, each with its own series of shifting scales and transitions, while the movement through the levels can take place via steps or a sloped grass berm that extends from the dining and kitchen garden to the master bedroom verandah below.
Externally the house is viewed from 2 critical points, the first being as one drives up the hill, where it is dominated by the existing, partially reconstructed and excised retaining wall with its deep pointed black rubble masonry, a vocabulary that is indigenous to the various small and medium size forts that still exist in the region. A triangular plane of zinc cantilevers over the first portion of the wall, while a tube of concrete pushes out over the far end.
The second point of visual contact occurs at the main entrance of the house (also seen from house 1), where a linear ‘veil’ of stone baskets ensures privacy except through strategically located openings where framed views of house 1 can be seen from within. The stone ‘veil’ was designed to allow random perforations within the assembly. Residual masonry from the site was filled into expanded mesh baskets which were stacked to create a gabion wall. The size of the baskets was determined after numerous tests to ascertain the density of settling and the percentage of gaps for light. We deliberately picked a flexible mesh that allowed the baskets to gently warp as the stones settled, creating the impression of a gradually undulating fabric rather than a rigid wall in certain light conditions.
The shaded network of spaces within the labyrinth creates a comfortable micro-climate that stays anywhere between 2-5 degrees centigrade below the ambient temperature. Glazed areas have been located based on the views and orientations to maximize cross-ventilation and open into deep shaded spaces or submerged courtyards, which allows the house to be naturally ventilated year round.
Rainwater is harvested from the roof garden and courtyards and directed towards a network of short bores which is used to charge the existing wells on the site.
All retaining walls, bar one, have been constructed using the locally available black ‘trap’ stone, most of which has been recycled from the excavation and from excised areas of the existing retaining wall, and by locating the structure on existing levels, we have managed to conserve considerable resources and have avoided tampering with the original contours of the hill as much as possible.