What is Roof Truss?

What is roof truss and what are the types of roof truss? In the stream of Structural Engineering, the word “truss”basically defines a triangular design. A joint framed structure that supported the inclined, vertical or horizontal loads. A truss comprises of eye bars, angles, plates and channels. The rood trusses are generally used for supporting the roofs of auditoriums, stadiums, cinema halls, airports, railways, stations and others.

Trusses are an incredibly solid, all around acknowledged, financially savvy alternative for the Construction of different structures. To expand the productivity of the structure (which is regularly estimated in the material utilized or labor), a fitting truss type ought to be chosen for the design. Here it is discussed about roof truss, types of roof truss, roof truss components, functions of roof truss, benefits and advantages of roof truss.

Function of Roof Truss

Having a roof over one’s head is a fundamental human need, one in which we’ve developed through hundreds of years of architectural ingenuity.  The roofing system has gone through an emotional change since its beginning of thatched roofs involved straw and reeds.  Here it is discussed about the roof truss, a complex architectural component which are the basic support of a roofing system.

Roof trusses are universal in building structures.  Even in case you’re new to a roof truss by its name, it’s almost certain you’ve spotted them before concealed in ordinary architecture.  A truss is a triangular structure coordinated into a roof to support a load.  Aside from lending support and solidarity to a roof’s frame, they likewise connect the space above rooms.

Types of Roof Truss

There are several types of roof truss. Some of the types of roof truss are as mentioned below.

King Post Truss

In this types of roof truss the main vertical post utilised that is working in tension to support a beam beneath from a truss apex. This truss usually spans up to 8 meters, which makes it ideal for numerous types of houses, particularly the more modest ones.

Queen Post Truss

In this types of roof truss an entirely dependable, simple and flexible type of roof truss where you can use at some random time. This sort of truss offers a span of around 10m, and has a simple design which makes it ideal for a wide scope of foundations.

Howe Post Truss

The howe truss is a  kind of truss having upper and lower members, a blend of steel and wood or both. This truss is very remarkable because of one thing that is it has an exceptionally wide span, as it can cover anything from 6 to 30 m. This types of roof truss is exceptionally valuable for a wide scope of undertaking types.

Pratt Truss

The prat truss is the most mainstream steel truss since it is exceptionally efficient. It incorporates vertical and diagonal members that slope down towards the middle. This types of roof truss can cover the  lengths that is ranging between 6 to10 m.

Fan Truss

In this types of roof truss a  simple design is made out of steel. Most ventures with larger span of around 10 to 15 m uses this sort of truss.

Quadrangular Truss

The quadrangular trusses are the types of roof truss that are having parallel chords and organising of web members of compression verticals and tension diagonals. It is for the most part experienced in auditoriums or railway sheds.

North Light Roof  Truss

This types of roof truss have a wide arrangement of lattice girders that incorporate support trusses. North light truss is the most established, and most affordable sort of truss. These are found in drawing rooms, industrial buildings and huge spaces, with a span of 20 to 30 m.

Raised Heel Roof Truss

This types of roof truss gives a savvy approach to meet more rigid energy proficiency codes and further develop the energy effectiveness of your building envelope. Raising the truss higher significantly improves on attic ventilation and it leaves sufficient space for insulation above outside wall top plates

Parallel Chord Roof Truss

The parallel chord roof truss are the types of roof truss that are constructed with two chords which are running parallel to one another and these are supported by reinforcing trusses in middle of the bottom and top chords. This types of roof truss lessens the condensation issues and mold conditions since they make a fume hindrance.

Scissor Roof Truss

In this types of roof truss the bottom chord members cross one another, associating with the calculated top chords at a point intermediate on the top chords’ length, making an appearance like an opened pair of scissors. A scissor truss accommodates a vaulted ceiling in similar time span as standard trusses. Cathedral is perhaps the best illustration of this sort of truss.

Components of Roof Truss

  1. Apex:  It is the highest point in where the sloping top chords join.
  2. Bearing: It is the structural support of trusses that are typically with a timber wall plate.
  3. Bottom Chords: It is the most reduced longitudinal member of the truss.
  4. Cantilever:  It is a part of structural member that is extended past its support.
  5. Cantilever Strut:  It is the web that joins the chords of bottom part over bearing point to the chords of top part of the cantilevered truss.
  6. Chord:  It is the main member that structure the outline of a truss and subjected to somewhat enormous axial force and bending moment.
  7. Clear Span:  It is the horizontal distance between the inside edge of the supports.
  8. Heel: It is a  point on a truss whose top and bottom chord converges.
  9. Joint: It is the  point of crossing points of atleast one web with a chord.
  10. Nail Plate:  It is the galvanized steel plate that is punched to shape a nail design indispensable with the plate and used to associate timber members.
  11. Node:  It is the point of convergence of at least two members that makes up the panels of a truss.
  12. Nominal Span: It is the  horizontal distance between the outside edges of the supports which are typically the tie beam length.
  13. Overhang:  It is the extension of the top chord of a truss past the bearing support.
  14. Panel: It is a  truss segment characterized by two adjacent joints or nodes.
  15. Plumb Cut:  It is the vertical slice to end of the top chord to accommodate vertical installation of the gutter or fascia.
  16. Splice Point: It is the top cord and bottom cord splice.
  17. Square Cut:  The square cuts are perpendicular to the edge of the chord.
  18. Stub End:  It is a truss type shaped by the truncation of a typical triangular truss.
  19. Top Chord or Rafter:  It is a horizontal member that sets up the upper edges of a truss.
  20. Web:  These are the members that join the bottom and top chords to shape a triangular example.

Benefits of Roof Truss

A roof truss is a functional component of a roofing system that offers way to different benefits for a homeowner.  A roof truss which is supported by a strong roof is a functional roof and healthy, and with that it comes the capacity for the roofing systems to appropriately divert the unsafe UV rays and keeping the UV radiation from infiltrating the home. This implies the roof will perform ideally during long stretches of exceptional weather, hot or cold, working to direct the interior temperature of the house to accomplish a happy with living environment.

The various types of roof trusses offer differing advantages to a building’s structure.  For instance, a parallel chord roof truss, made from two chords parallel to each other with supports in the middle, makes an ideal fume boundary that pursuits away condensation and mold.  A Pratt roof truss, just spanning around 6 to10 m, offers builders a prudent choice for a roof truss, and a raised heel roof truss is helpful for insulation, energy proficiency and attic ventilation.

Advantages of Roof Truss

  1. The steel trusses are more stronger than timber trusses.
  2. Steel area shaping the truss are lightweight and can be manufactured in any ideal instance to suit the architectural prerequisite.
  3. There is no risk of the materials being consumed by white ants or different insects.
  4. Steel trusses are more fire-opposing than timber trusses.
  5. They don’t have span limitations and as such steel trusses can be utilized for industrial buildings and other such structures where huge regions are needed to be covered without obstructions because of columns and so on.
  6. The areas that are shaping a steel truss are simple in the transportation.
  7. The areas can be acquired in any ideal structure or length to suit the requirements and there isn’t a lot of wastage of the material in cutting and so on.
  8. On record of their simple erection strategies, the advancement of roofing work with steel trusses is quick.

Here it is discussed about roof truss, types of roof truss, roof truss components, functions of roof truss, benefits and advantages of roof truss.