Difference Between Rafter and Truss | What Is Rafter | What Is Truss

Difference Between Rafter and Truss What Is Rafter What Is Truss

Introduction of Difference Between Rafter and Truss.

The Roof Framing system has undergone a huge revolution over the last some years. The main function of the Rafters and Trusses is to support the roof of the structure. If you are constructing your new home, then you may be confused that what should use to support the roof.

Many people are confused and don’t know what are the trusses and rafters and which one should be the best option for your building.

In this article, we will highlight the Difference between Rafter and Truss and which one you should use in the construction of your home.

Also Read: What Is Building | Types of Building

What Is Rafter?

What Is Rafter

Rafters are the Roof Framing system that is traditionally used in the construction of various structures. In simple words, the rafters are the planks of wood.

The Rafters slope from the central ridge of the beam to the top most part of the roof. Rafter includes a sloping outer beam which mainly provides support to the roof.

Rafters are assembled on the construction site. Rafters are fabricated on the construction site which will lead to the wastage of the materials and time due to which the cost of the project increases.

The Rafter are generally used in the building which is smaller than 6 meters. It is generally used for small-scale construction projects.

Rafters are very easy to modify and innovate in future without affecting the roof of the structure. Rafters are used key component in the construction of the roof structure.

Rafters are generally made from timber or steel. The size of the Rafters can be increased if larger roofs spans are required.

Advantages of Rafter

  1. More head height in the attic.
  2. Can be used anywhere.
  3. Ideal for small construction projects.
  4. Reduced lead time.

Disadvantages of Rafter

  1. Costly.
  2. More time-consuming.
  3. Skilled workers required.
  4. Slower pace of building.

Also Read: 20 Types of Construction Beam & Their Uses

What Is Truss?

What Is Truss

Truss is basically a Framework which is made from Timber and have a triangular shape which generally provides structural support and stability to the roof.

Trusses are generally prefabricated and mainly consist of two forces members. Trusses are prefabricated so that they can be directly installed on the Construction sites.

Trusses have more triangle webs inside the principal frame. As the trusses consist of a network of various beams in the triangular shape, the beams are distributed all over the roof due to which there will be an even weight distribution all over the roof.

The Trusses are prefabricated in the factory due to which they can be directly installed on the construction site which makes it more affordable compared to the rafters.

Trusses are suitable for the construction of large-span structures which can span up to 35m. Trusses are interconnected members which makes it difficult to renovate or modify it in the future.

Advantages of Truss

  1. Less expensive.
  2. More accuracy.
  3. Quicker construction.
  4. Greater strength.
  5. Diy friendly.

Disadvantages of Truss

  1. Big weight and size.
  2. Limitations in-ceiling design.
  3. No future alternations possible.
  4. No room for storage or conversion.

Also Read: What Is Pier and Beam Foundation | Advantages & Disadvantages of Pier and Beam Foundations | Pier and Beam Foundation Design | How to Build a Post and Pier Foundation

Difference Between Rafter and Truss

Difference Between Rafter and Truss

The difference between Rafter and Truss according to their properties and various factors are as follows.

Sr.No. Rafter Truss
1 Rafters are not prefabricated, they are built on the construction site.
Trusses are prefabricated and constructed in the factory and then shipped to the construction site.
2 Rafters provide less support and stability to the structure as compared to the Trusses.
Trusses provide more stability and support to this structure because of the web of triangles inside the mainframe.
3 The construction of the Rafters is very time-consuming.
The construction of the Truss required very less time.
4 Rafters consist of two main outer beams which support to the roof of the structure.
Trusses consist of multiple beams which add more support to the structure.
5 Rafters are simple in look.
Trusses add aesthetical beauty to the structure.
6 The Rafters are suitable for the construction of small space areas such as a small house or car shed etc.
The trusses are suitable for the construction of large space areas such as big houses and godowns etc.
7 Installation of the rafters is more expensive as compared to the Trusses.
The cost of installation of the trusses are less than the rafters
8 The modification and the renovation of the rafters are very easy and simple.
The modification and the renovation of the Trusses are very complex.
9 Rafters have less strength as compared to the Trusses.
Trusses have greater strength.
10 Installation of the rafters required skilled labour.
Installation of the trusses does not require skilled labour.
11 Rafters have a shorter lead time.
Trusses take a longer time for its installation.

Conclusion of Rafter and Truss

The Trusses are prefabricated in the factory due to which it is manufactured under skilled supervision due to which the Trusses are of superior quality, whereas the rafters are fabricated on the construction site by the labours and workers under the supervisor which may affect the quality of the Rafters.

The use of the Trusses are more preferred as compared to the Rafters because of their cost and.


What Are Rafters in a House?

In the field of construction, rafters are a series of sloped structural pieces that will extend from a ridge area to the plate of a wall or an eave. They are used to support the load of the building, especially the roof area.

What Is a Roof Rafter?

A rafter is one of a series of sloped structural members such as wooden beams that extend from the ridge or hip to the wall plate, downslope perimeter or eave, and that are designed to support the roof shingles, roof deck and its associated loads.

What Is a Jack Rafter?

A secondary roof timber (as a common rafter resting on purlins) also : one of the pieces simulating extended rafters under the eaves in some styles of building.

What Is a Common Rafter?

One of a series of rafters of uniform size regularly spaced along the length of a pitched roof, or placed as intermediates between principals, with one end attached to the wall-plate and the other to the opposite common rafter at the ridge. A pair of common rafters is a couple.

What Is a Roof Truss in Construction?

A roof truss is a prefabricated structure designed to support a roof on a building. They come in two main types: flat and pitched. Those types can be broken down into more specific roof truss types that can suit all manner of construction projects.

Disadvantages of Timber Roof Trusses

Wood can rot or become infested with bugs if not maintained and treated properly. Timber is also more likely to become damaged by adverse weather conditions or lifting in high winds. Timber tends to be more cost effective than metal, it is still a popular roof truss materials choice.

What Is a Truss Structure?

A truss is essentially a triangulated system of straight interconnected structural elements. The most common use of trusses is in buildings, where support to roofs, the floors and internal loading such as services and suspended ceilings, are readily provided.

What Is Simple Truss?

A truss is a structure composed of slender members joined together at their end points. A simple truss is a planar truss which begins A simple truss is a planar truss which begins with a triangular element and can be expanded by adding two members and a joint.

What Does a Truss Do?

A truss is a series of individual members, acting in tension or compression and performing together as a unit. On truss bridges, a tension member is subject to forces that pull outward at its ends. Even on a “wooden” truss bridge, these members are often individual metal pieces such as bars or rods.

Advantages of Truss

The main advantage of trusses is that they are fast and cost-effective to install and do not require heavy expensive equipment or excessive preparation in order to be used effectively. Trusses are generally built in a factory and delivered as a complete set to a job site, where the structure is then built.

Disadvantages of Truss

One of the most important disadvantages of Truss structure is that it requires a lot of space because the interconnected triangular components must be large to withstand and distribute heavy loads. In addition, their high maintenance costs are also important disadvantages.

What Is the Difference Between Trusses and Rafters?

One of the main differences between truss roofs vs. rafters is the fact that trusses are prefabricated wooden structures while rafters are usually built on-site. For trusses, the triangular webbing of structural pieces not only provide support for the roof, but they also tie the outside walls of the home together.

Calculating Roof Rafters

How to calculate rafter length?

  1. For calculations based on the roof rise: rise² + run² = rafter length² , meaning that: rafter length = √(rise² + run²) .
  2. For calculations based on the roof pitch:

Hip Rafter

The rafter extending from the wall plate to the ridge and forming the angle of a hip roof.

Types of Rafters

The most common types of rafter include:

  • Principal rafter: Usually the largest type of rafter located at the ends of a roof structure.
  • Common rafter: Smaller rafters located in between the principals at both ends.
  • Auxiliary rafter: Less common but can be used to support and reinforce a principal rafter.

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