Share this:
If you do not work within the construction industry, you may not know what purlins are. However, if you operate within this industry, you will likely see and work with them every day. Purlins are crucial in many construction projects, so it pays to know about them if you want your building to be structurally sound.
There are many types and sizes of steel purlins for sale, and if you are in construction, you probably want to establish a go-to company from which you will buy them. Before you reach that point, though, you should know about some of the most common types of purlins and pros and cons associated with each one.
Photo by Yiğit Efe Şeref: https://www.pexels.com/photo/clock-hanging-under-ceiling-17445483/
What Exactly is a Purlin, Anyway?
A purlin is a type of structural support element that goes into the construction of many types of buildings. It is generally used in roofing and supports the roof’s cover.
If you look at the ceiling of many types of buildings, you will immediately be able to see the purlins. Their distinct shape and the purpose they serve in holding up the building’s roof make them a conspicuous part of the design of many structures.
Now, let us look at five types of purlins and the positives and negatives that go along with them.
Steelbone Purlins
The steelbone purlin is one you will often see with smaller structures. If you’re interested in their most prominent pros, among them is the fact that they have an enclosed design that makes it much more difficult for birds to perch and nest there. They also allow for very little buildup of dust.
They are among the fastest purlins to install in most instances. They provide excellent clearance and utilize available space efficiently.
On the negative side, they can only span limited amounts of space, usually about 10m or so. They also are often more expensive than their open counterparts. This is because they use more steel. More steel usually equals a higher overall price tag, which any construction company or architect will want to consider.
Timber Purlins
Timber purlins are generally most prized because they have strong thermal insulation properties. They also have natural aesthetic appeal, with material that looks perfectly at home in several kinds of construction projects. They are of a much lighter weight than steel as well, which makes them easier to handle and move during the construction process.
On the negative side, they are susceptible to being gnawed on by pests. They can rot, and they can be damaged by moisture. As time passes, they may start to sag due to environmental factors, leading to roof instability. They may require more maintenance than their steel counterparts as the years go by as well.
U Purlins
U purlins are one of the more common varieties you will see in modern buildings. They offer specific benefits for certain designs, and they can also be more cost-effective than some of the other options on this list.
On the negative side of things, they are less common than the C or Z purlins we are about to discuss, so it can be a little harder to find a company that carries them. This can be particularly problematic if you are trying to buy them in bulk for an upcoming project. They may also not have quite the versatility or the strength of some of the other types that are out there.
Z Purlins
The Z purlin is one of the most common types, as you will see them more than any of the other three we have discussed so far. Z purlins have an overlapping design that contributes to their overall strength and stability. They are ideal for holding up heavier roofs.
They can also be used in many more building types than other purlins, like the U purlins we were just discussing. They are ideal if you are trying to distribute a load so that various parts of the roof’s primary framing are holding it up equally. Their angled edges allow for nesting, and they are easy to store and transport.
They are not so great from the standpoint of a project’s overall price tag, though. They will almost always cost more than most of the others on this list. They also sometimes require complex fixing techniques as a building gets older. Their installation time can be more lengthy than some of the others you might choose to use.
C Purlins
C purlins are used just as much as Z purlins, and more than the other three on the list. They are perhaps the easiest to install of any of the five we have talked about, which is why you see them nearly everywhere. They offer strong support and can cover long distances with ease.
They also require minimal cutting or other modifications. They are virtually guaranteed not to bend. They are usually thought of as being one of the most cost-effective options if you’re trying to bring down the overall price of a construction project.
There are a few negatives associated with them, though, much like any of the others on this list. Probably the most significant one is that they may not be suitable for the longest of spans. They are also not the best choice if you are trying to hold up the heaviest of roofs.
In addition, they are favored by birds. Unlike some of the others we mentioned, like the steelbone purlin, if you install them when erecting something like a stadium, it’s highly likely you will end up with birds nesting there.
The mess and damage birds can cause over time should not be underestimated. This one factor alone sometimes persuades some architects to steer clear of this choice.
If you look at these five types of purlins, you can see relatively easily which ones are more suitable for many projects. However, we should stress that there is no perfect purlin. No matter which one you choose, it will have some positives, but also some notable drawbacks.