A technique of brick-and-lime flat roof construction, named after the erstwhile Madras Presidency of colonial South India where it emerged. Small, thin burnt bricks called achikal or kandikal are laid, with lime mortar, horizontally on edge over closely spaced wooden rafters, at a diagonal to the plan. Another layer of bricks is laid flat over these, in the perpendicular direction, with any subsequent layers similarly alternated. The joints are filled using jaggery water, followed by lime mortar slurry, and the top surface may be finished with pressed roof tiles, or floor finishing if there are further storeys. The Madras terraced roof was developed and codified by British engineers in the eighteenth century, adapting small-scale roofing systems traditionally used in homes and temples across southern India. Its fire- and water-resistance and low maintenance extended its application to larger span structures such as public buildings, with steel girders replacing wooden beams.