A roof is the top covering of a building, including all materials and constructions necessary to support it on the walls of the building or on uprights, providing protection against rain, snow, sunlight, extremes of temperature, and wind. A roof is part of the building envelope.
Thatching is the craft of building a roof with dry vegetation such as straw, water reed, sedge, rushes, heather, or palm branches, layering the vegetation so as to shed water away from the inner roof. Since the bulk of the vegetation stays dry and is densely packed—trapping air—thatching also functions as insulation. It is a very old roofing method and has been used in both tropical and temperate climates. Thatch is still employed by builders in developing countries, usually with low-cost local vegetation. By contrast, in some developed countries it is the choice of some affluent people who desire a rustic look for their home, would like a more ecologically friendly roof, or who have purchased an originally thatched abode.
A chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator, or fireplace from human living areas. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney effect. The space inside a chimney is called the flue. Chimneys are adjacent to large industrial refineries, fossil fuel combustion facilities or part of buildings, steam locomotives and ships.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
A mansard or mansard roof is a multi-sided gambrel-style hip roof characterised by two slopes on each of its sides, with the lower slope at a steeper angle than the upper, and often punctured by dormer windows. The steep roofline and windows allow for additional floors of habitable space, and reduce the overall height of the roof for a given number of habitable storeys. The upper slope of the roof may not be visible from street level when viewed from close proximity to the building.
A dormer is a roofed structure, often containing a window, that projects vertically beyond the plane of a pitched roof. A dormer window is a form of roof window.
A flat roof is a roof which is almost level in contrast to the many types of sloped roofs. The slope of a roof is properly known as its pitch and flat roofs have up to approximately 10°. Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used as a living space or a living roof. Flat roofs, or "low-slope" roofs, are also commonly found on commercial buildings throughout the world. The U.S.-based National Roofing Contractors Association defines a low-slope roof as having a slope of 3 in 12 (1:4) or less.
A saltbox house is a gable-roofed residential structure that is typically two stories in the front and one in the rear. It is a traditional New England style of home, originally timber framed, which takes its name from its resemblance to a wooden lidded box in which salt was once kept.
A snow cave is a shelter constructed from snow by certain animals in the wild, human mountain climbers, winter recreational enthusiasts, and winter survivalists. It has thermal properties similar to an igloo and is particularly effective at providing protection from wind as well as low temperatures. A properly made snow cave can be 0 °C or warmer inside, even when outside temperatures are −40 °C.
Roof pitch is the steepness of a roof expressed as a ratio of inch(es) rise per horizontal foot, or as the angle in degrees its surface deviates from the horizontal. A flat roof has a pitch of zero in either instance; all other roofs are pitched.
Domestic roof construction is the framing and roof covering which is found on most detached houses in cold and temperate climates. Such roofs are built with mostly timber, take a number of different shapes, and are covered with a variety of materials.
Bituminous waterproofing systems are designed to protect residential and commercial buildings. Bitumen is a material made up of organic liquids that are highly sticky, viscous, and waterproof. Systems incorporating bituminous-based substrates are sometimes used to construct roofs, in the form of "roofing felt" or "roll roofing" products.
Asphalt roll roofing or membrane is a roofing material commonly used for buildings that feature a low sloped roof pitch in North America. The material is based on the same materials used in asphalt shingles; an organic felt or fiberglass mat, saturated with asphalt, and faced with granular stone aggregate. The installation process, known as Torch On Roofing, is often used on commercial properties in North America.
Ponding is the (typically) unwanted pooling of water, typically on a flat roof or roadway. Ponding water accelerates the deterioration of many materials, including seam adhesives in single-ply roof systems, steel equipment supports, and particularly roofing asphalt. On low-slope asphalt roofs, ponding water allows the oil solvent components of the asphalt to leach out and evaporate, leaving the roof membrane brittle and susceptible to cracking and leaking in the ponding location. The time taken for water to saturate a zone, usually from rainfall, causing a pond to form, is referred to as the "ponding time" or "time of ponding".
Roofline is used to describe the fascia, soffits, bargeboards and antefixes that forms the frontage immediately below the roof and the eaves of many homes and buildings. These are traditionally made from wood, but can be made of a variety of different materials, including plastic, such as polyvinyl chloride.
A hip roof, hip-roof or hipped roof, is a type of roof where all sides slope downwards to the walls, usually with a fairly gentle slope. Thus, a hipped roof has no gables or other vertical sides to the roof.
A Bresse house is a timber-framed house of post-and-beam construction, that is infilled with adobe bricks and is typical of the Bresse region of eastern France. A large hip roof protects the delicate masonry from rain and snow. The house is almost always oriented in a north–south direction, the roof on the north side often being lower. This configuration offers the optimum protection from the bise, a cold northerly wind typical of the region, which is deflected over the house by the low, sweeping roof on the northern gable end. The living rooms are on the south side, the main façade facing the morning sun. Usually each room has one or two outside doors, so that no space is sacrificed for passages.
