|
Modern standing-seam roofs are a clear favorite over other styles of roof applications on the market today. The through-fastened structure’s roof–once the building industry standard—has now been superseded by the standing-seam roof, which has some unique components. The high seams of the side-by-side standing-seam panels are formed in the field by a seaming tool, rendering them superior to those that are screwed down and lapped together. Proper sealing is put in the seam corrugation and is applied at the building production facility. To allow for expansion and contraction, panels are attached to purlins with fasteners that allow some roof movement.
The grooved sheets of a standing-seam roof have been seamed, and require clips attached to allow the sheets to become a single unit, as a roof layer, that can adjust with temperature fluctuations. Close to 66 yards is usually the maximum steel building roof width that can be planned for. Building expansion joints can be used if more width is required.
There are many types of clips for standing-seam roof designs that enable different locations for tab movement. These clips come in many sizes and shapes but they all perform the same function. Fastening is achieved when the immoveable base of the clip is attached to the purlin and the adjustable tab is rolled into the seam. To support motion up and down the roof pitch, all clips are usually pre-set. The length of the slot and the size of the tab establish this motion. It is generally recognized that one of the best clips to use is the articulating clip. Stainless steel clips are preferable in quality over the galvanized variety. If you wish to save both time and money, consider having all roof components and purlins pre-punched by a single fabricator.
Depending on the manufacturer, you will find that rooftop elements differ. The optimum length of any pre-engineered steel roof element is less than 40 ft. due to handling practicalities such as shipping and assembly. Panel splicing will be required for roofs which are greater in width. End splices can be reinforced by pre-punching and clamping plates rather than the usual panel-to-panel stagger. Roof structures are susceptible to a number of problems so it is advisable that you ensure lap placement is well-supervised.
There are two main groups of seam designs for standing-seam steel building roofs. One design is upright, while the other is trapezoidal. The latter is the more commonly used seam as it allows for concealment of the clip, and because of its temperature enlargement and contraction characteristics. A large number of building producers modify the air movement fluctuation and noise cutback, together with proper firmness aspects. Any specific furrow spacing and also the distance across the pre-engineered roof components may be different depending on the producer.
Over three quarters of through-the-roof fasteners that are commonly used in other rooftop applications are not needed with a standing-seam roof. However, to adapt to design enlargement, they are essential in the through-fastening of the panels along the eave strut.
| 
