A communal rumah gadang is a long house, rectangular in plan, with multiple gables and upsweeping ridges, forming buffalo horn-like ends. They normally have three-tiered projections, each with varying floor levels. They are broad and set on wooden piles that can reach as high as 3 meters (10 feet) off the ground; sometimes with a verandah running along the front face of the house which is used as a reception and dining area, and as a sleeping place for guests. Unlike the Toba Batak homes, where the roof essentially creates the living space, the Minangkabau roof rests on conventional walls. Cooking and storage areas are often in separate buildings.
The house is largely constructed of wood; an exception being the being the rear longitudinal wall which is a plain lattice woven in a chequered pattern from split bamboo. The roof is of a truss and cross-beam construction, and is typically covered with thatch from the fibre of the sugar palm (ijuk), the toughest thatch material available and said to last a hundred years. The thatch is laid in bundles which can be easily fitted to the curved, multi-gabled roof. Contemporary homes, however, are more frequently using corrugated iron in place of thatch. Roof finials are formed from thatch bound by decorative metal bindings and drawn into points said to resemble buffalo horns – an allusion to a legend concerning a battle between two water buffaloes from which the ‘Minangkabau’ name is thought to have been derived. The roof peaks themselves are built up out of many small battens and rafters.
The women who share the house have sleeping quarters set into alcoves – traditionally odd in number – that are set in a row against the rear wall, and curtained off by the vast interior space of the main living area. Traditionally, large communal rumah gadang will be surrounded by smaller homes built for married sisters and daughters of the parent family. It is the responsibility of the women’s maternal uncle to ensure that each marriageable woman in the family has a room of her own and to this end will build either a new house or more commonly additionally annexes to the original one. It is said that the number of married daughters in a home can be told by the counting its horn-like extensions; as they are not always added symmetrically, rumah gadang can sometimes look unbalanced. Adolescent boys traditionally live in the village surau, a small mosque.