Types of Purlins & Things You Must Know Before Buying Purlin - Bansal Roofing

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Types of Purlins Things You Must Know Before
Buying Purlin
Purlin is a horizontal beam or bar used for
structural support in structures, most often
below the roof. Purlins are supported either by
the buildings rafters or its walls. These are
most commonly used in metal buildings, but in
wood-frame structures, these also replace closely
packed rafters. A roofs purlins support the
roof Decks weight. The roof deck is the wooden
panel, ply board, or sheet metal which creates
the roof surface. This is usually filled with
some kind of weather proofing and constructed
from concrete and often an insulation
material. There are many types of Purlins and
are divided into groups depending on the material
they are made of and the form of their shape.
Different purlins are used for multiple uses
including a structural wall or floor support.
Purlin is necessary as there is no frame for the
sheeting on the roof to rest on without it,
thereby making purlins important to the roof
structure.
What is Purlins?
Purlins carry the roof deck or sheathing loads
and are supported by large rafters and/or
building walls, steel beams, etc. In comparison
to closely spaced rafters, the use of purlins is
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common in pre-engineered metal construction
systems and both the ancient post-and-beam and
newer pole construction methodologies for frame
construction. Purlins pass roof loads to the
major structural elements supporting the roof
the form and arrangement of purlins is a design
factor that depends on the instance of roof loads
as well as the limiting sheeting lengths to use.
In the final analysis, local building codes
should always be understood and implemented in
the design of a concrete roof structure. Also
Read How To Keep Industrial Factory Cool Without
Air Conditioning? Steel Purlin
Steel purlins are a substitute for conventional
wood purlins. They are lightweight, stable in
dimension, accurate and simple. In extreme
temperature changes, they expand and contract
moderately. Steel purlin is typically made of
cold-formed material, which is thin enough to
get through the screws. Cold-formed steel is
rendered in the desired shape by rolling or
pressing thin sheets of steel in. To the
producer, it is less costly than hot-rolled steel
and is, therefore, simpler to deal with. Though
cold-formed steel is stronger than hot-formed
steel when under strain, it is more likely to
crack rather than bend. Purlins are made of
different metals. Some are simple Mild steel
having normal strength and some are with zinc
coating of different GSM. In harsh weather
special coating can be applied over and above
zinc coating. Types of Cold Formed Purlins C
Shaped Purlins
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C purlins, as the name implies, are formed as in
the C alphabet, which is primarily used to
support walls and floors. C section purlins or
cee section purlins are built to shape a building
shell structures walls and floor joists, making
them also suitable for supporting the beams
required for flooring. These may also use our C
segment purlins with door mounting, roof
clipping, window trimming, parapet rails, and
side rails. Both of our purlins in section C
have similar extensions on their ends, which mean
they can be used in single spans. These are
freestanding and secure, allowing them to be
easily managed while being mounted while also
offering stable support in the system. Sizes
Available for C Purlins Bansal C section
purlins are available in a wide range of
thicknesses and are manufactured to the exact
specifications of the customer up to any length,
enabling them to be easily modified for use in
buildings of various sizes. Bansal also
manufactures them un-drilled or with different
diameter pre-drilled holes (Oval shape and round
shape holes of any dimensions can be provided on
request). Web height up to 300 mm is available
and thickness up to 3.2 mm is available. Also
Read 10 Things To Consider Before Hiring An
Industrial Roofing Contractor Z Shaped
Purlin Another form of Z purlin is stronger
than C purlin and is mostly used together at
joints and overlaps. Z purlins or zed purlins
are horizontal beams that are built to shape a
building shell structures roof and wall joists.
They sit between the roofing sheets and the
building, acting as sheet support to ensure that
it is firmly attached and secure in place. Due to
its relatively
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high flexibility and lightweight properties Z
purlins are most commonly used in agricultural
and industrial buildings which make them easily
adapted for use in a variety of different
sizes. Sizes Available for Z Purlins At Bansal
Roofing Products Ltd, we manufacture Z purlins in
a broad range of thicknesses that can be
produced up to any length to suit your exact
requirements. We can also manufacture them
un-drilled or with any diameter pre-drilled holes
according to your requirements. (Oval shape and
round shape holes of any dimensions can be
provided on request). Web height up to 300 mm is
available and thickness up to 3.2 mm is
available. C Shaped SIGMA Purlins C shaped with
having special ribs (Bends in web) are known as
SIGMA purlins. These types of purlins are
having good structural properties and supersedes
above two varieties of purlins. Sigma section
purlins are built to shape a building shell
structures walls and floor joists, making them
also suitable for supporting the beams required
for flooring. These may also use our C segment
purlins with door mounting, roof clipping, window
trimming, parapet rails, and side rails. Sizes
Available for SIGMA Purlins Bansal SIGMA
section purlins are available in a wide range of
thicknesses and are manufactured to the exact
specifications of the customer up to any length,
enabling them to be easily modified for use in
buildings of various sizes. Bansal also
manufactures them un- drilled or with different
diameter pre-drilled holes (Oval shape and round
shape holes of any dimensions can be provided on
request). Web height up to 300 mm is available
and thickness up to 3.2 mm is available. What
Purpose Do Purlins Serve in a Steel Building?
To understand this we really need to get down to
the basics of roof purlins in metal
construction. Purlins are an integral part of a
pre-engineered structural steel package. Such
structural supports extend through the rafter
beams perpendicularly. Often known as sheeting
sheets, purlins provide the roofing portion of a
steel buildings secondary framing. Three
structural functions are provided by metal
roofing purlins.
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• Firstly, the roof is protected by the purlins.
  Second, purlins tie the rafters together,
  stabilizing and reinforcing the rigid framing of
  the frame. And the third, between the spans of
  the individual framing bays, purlins provide
  additional support. As an added benefit, purlins
  increase the resistance of the system to
  excessive rainfall.
• Also Read 5 Benefits Of Pre-Engineered Buildings
  (PEBs)
• Why are Purlins Considered Reliable Building
  Materials?
• Height of buildings rising almost to the sky,
  apartments, factories and warehouses can be seen
  everywhere you go. This concrete jungle has now
  become peoples backbone to get a perfect place
  to rest, work, dine, and do other things. What
  needs to be understood is how these high rise
  buildings as well as several hectares of
  warehouses are built using highly strong
  materials.
• A variety of construction materials available on
  the marketplace are the very thing that makes it
  look so amazing to build, factories and other
  facilities and allow it to last longer
  effectively. Purlin is one of those highly common
  architectural materials among varied materials
  that can be used efficiently to help and support
  roof deck or sheathing.
• Why one should buy Purlins made by Bansal
• Bansal Purlins are made in automatic machines
  with a Pre Cut and Pre punch facility.
• Bansal Purlins gives dimensions accuracy thus
  easy installation at site.
• Bansal Purlins are made in different thicknesses,
  Web, GSM Coating and tensile strengths.
• We manufacture C, Z and Sigma Purlin to
  make a complete range of cold rolled
• purlins under one roof.
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