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Uses of roof, types of roof and parts

Short answer

Roofs protect from rain, sun, wind, provide privacy, support services, and create extra space. Types: flat (slope ≤10°), pitched (slope >10°: lean-to, gable, hip, gambrel, mansard, etc.), curved (shell, dome, vault), and combination. Pitched roof parts: ridge, hips/valleys, eaves, rafters, purlins, battens, tie beam, wall plate, covering. Flat roof parts: RCC slab, screed, waterproofing, finishing, parapet, rainwater pipes.

What is roof used for? Sketch out different types of roof and show their parts.

Uses of a roof

A roof protects people and property from rain, snow, sun, heat and wind, gives privacy and security, supports services (tanks, solar panels), and provides extra space (terrace, attic).

Types of roof with parts

Roofs are classified as:

  1. Flat roofs: nearly horizontal (slope up to 10 degrees, about 1 in 40 to 1 in 60 for drainage); RCC or stone slab, jack-arch and terrace roofs.
  2. Pitched (sloping) roofs: slope more than 10 degrees; covered with tiles, slates, sheets or thatch over timber or steel frames. Types: lean-to, gable (couple), hip, gambrel, mansard, hip-and-valley, north-light, butterfly, conical.
  3. Curved (shell) roofs: shell, dome, vault, barrel and folded plate roofs for large halls.
  4. Combination roofs: part flat and part pitched on the same building (for example, a flat RCC terrace with a sloping tiled or sheet roof over one part).
 Lean-to       Gable (couple)    Hip
    /|             /\            /--\
   / |            /  \          /    \
  /__|           /____\        /______\

 Mansard           North light
   ____             /|  /|  /|
  /    \           / | / | / |
 /      \         /__|/__|/__|
 |      |

Parts of a pitched roof

              ridge
               /\
              /  \    <- rafter
     rise ->  /    \
             /      \
   eaves ->_/________\_<- eaves
         wall plate  wall
         |<-- span -->|

Main parts: ridge (the top line where the slopes meet), hips and valleys (the inclined external and internal angles), eaves (the lower overhanging edge), rafters (the inclined supports), purlins (the horizontal supports under the rafters), battens, tie beam, wall plate and the roof covering.

For a flat roof the parts are: RCC slab, screed (brick bat coba or lean concrete) to give the slope, waterproofing layer, finishing (tiles), parapet wall with coping, and rainwater pipes (RWP).

✓ Answer checked by Claude Opus 5.5 (high effort)

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