# How are roof loads distributed?

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Loads are considered to be either distributed or point loads. A layer of sand spread evenly over a surface is an example of a pure distributed load. Each square foot of the surface feels the same load. Live and dead loads listed in the building code for roofs and floors are approximations of distributed loads.

## Which component carries the load from roof?

The member spanning from truss to truss which is meant to carry the load of the roofing material and to transfer it on the panel points is called a purlin. Hence the length of the purlin is equal to the width of the bay, i.e., the spacing of the trusses. The various components of the truss are shown in Fig. 12.1.

## How does a truss distributed load?

The roof is connected to the truss through the joint points and so the roof load is distributed to each of the joints as concentrated forces. However, the distribution is not equal. The outside two joints (A and C) will only carry half of what the center joint will carry.

## How are loads distributed in structural system?

Gravity load is the vertical load acting on a building structure, including dead load and live load due to occupancy or snow. Gravity load on the floor and roof slabs is transferred to the columns or walls, down to the foundations, and then to the supporting soil beneath.

## What are some examples of live loads?

Typical live loads may include; people, the action of wind on an elevation, furniture, vehicles, the weight of the books in a library and so on. A live load can be expressed either as a uniformly distributed load (UDL) or as one acting on a concentrated area (point load).

The dead load of a typical asphalt-shingled, wood-framed roof is about 15 pounds per square foot. The load increases with the use of heavier roofing material.

## What are the 3 types of trusses?

Common types of roof truss

• King Post truss. A king post truss is typically used for short spans. …
• Queen Post truss. A queen post truss is typically a vertical upright with two triangles either side. …
• Fink truss. …
• Double Pitch Profile truss. …
• Mono Pitch Truss. …
• Scissor Truss (also known as Vaulted Truss) …
• Raised Tie Truss.

## What does Roof live load mean?

The weight of temporary objects on the roof is referred to as the live load. Live loads include the roofing crew and the equipment and tools they bring with them. A roof must be able to support both its dead load and live load at any given time.

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## Which load is not considered on roof truss?

Which of the following load combination is not considered for design of roof trusses? Explanation: Earthquake loads are not significant for roof trusses because of the small self weights.

## What makes a truss strong?

Load-bearing capacity of truss bridges is huge due to the structure of interconnecting triangles. The structure effectively manages both compression and tension by spreading the load from the roadway throughout its intricate structure.

## How does a roof truss support a roof?

Trusses are pre-fabricated, triangulated wooden structures used to support the roof. The alternative is to build up the roof’s frame with 2x8s and 2x10s. … You can span a large distance with a truss and the truss transmits all of the weight to the exterior walls.

## What makes a truss efficient?

The depth of a truss, or the height between the upper and lower chords, is what makes it an efficient structural form. A solid girder or beam of equal strength would have substantial weight and material cost as compared to a truss.

## What are the 3 types of loads?

The types of loads that act on building structures and other structures can be broadly classified as vertical, horizontal, and longitudinal loads.

## What is an example of a dynamic load?

Dynamic loads include people, wind, waves, traffic, earthquakes, and blasts. Any structure can be subjected to dynamic loading.