Roofs provide protection from weather elements like rain, heat, snow, and wind. They consist of structural frameworks at the top of buildings to support roof coverings. There are different types of roofs including flat roofs, pitched roofs, and curved roofs. Loads on roofs include dead loads from structural weight, imposed loads from movable objects, wind loads, snow loads, and earthquake loads. Dead loads comprise permanent structural weights while live loads are from movable partitions and furniture. Wind and snow loads are calculated based on velocity and accumulation amounts, and earthquake loads induce both vertical and horizontal forces.

1. • The uppermost part of a building
which is constructed in the form of
framework to give protection to the
building against rain, heat, snow,
wind, etc.
• A roof basically consists of structural
elements provided at the top of the
building for the support of roof
coverings

2. Types Of Roof
Flat Roof Pitched Roof Curved Roof

3. LOADS ON ROOF
• Types of loads acting on a structure are:
• Dead loads
• Imposed loads
• Wind loads
• Snow loads
• Earthquake loads

4. Dead Load
• Dead load is primarily due to self weight of structural
members.
• It majorly consists of the weight of roofs, beams, walls
and column etc. which are otherwise the permanent
parts of the building.
Live Loads
• Live loads are either movable or moving loads with out
any acceleration or impact.
• These loads are assumed to be produced by the intended
use or occupancy of the building including weights of
movable partitions or furniture etc.

5. Wind Load
• Wind load is required to be considered in structural
design especially when the heath of the building exceeds
two times the dimensions transverse to the exposed wind
surface.
• The calculation of wind loads depends on the two
factors, namely velocity of wind and size of the building.
Snow Load
• Snow load is the downward force on a building'sroof by
the weight of accumulated snow and ice. The roof or the
entire structure can fail if the snow load exceeds the
weight the building was designed to shoulder. Or if the
building was poorly designed or constructed

6. Earthquake Load
• Earthquake forces constitute to both vertical and
horizontal forces on the building.
• The total vibration caused by earthquake may be
resolved into three mutually perpendicular directions,
usually taken as vertical and two horizontal directions.
• The movement in vertical direction do not cause forces in
in superstructure to any significant extent. But the
horizontal movement of the building at the time of
earthquake is to be considered while designing.