by Rebecca Walker — May 6, 2011—Architectural Building Components (ABC) has introduced Symmetrical Panel Systems for roofs. The company says its existing 238T is an ideal panel for low slope retrofitting and reroofing. However, it adds that the new 138T’s lower profile makes it a more aesthetically appealing option for steep slope new construction. By expanding ABC’s symmetrical product line the opportunities for standing seam metal roofing multiply, notes the company.
The most measurable benefit of ABC’s symmetrical panel design is individual panel replaceability and repairability, says the company. Structural metal panels have historically been un-modifiable due to their asymmetrical design and permanent, 180 degree mechanical seaming that occurs to make the roof watertight. Since symmetrical panels have no interlocking seams, only one panel needs to be removed for repairs. The design also gives installers better control over where panels can be installed. Allowing the installer to choose where they start on the roof: a center start installation or even running simultaneous crews on different parts of the roof — drastically decreases their total labor time.
In standard asymmetrical panel systems, the clip is not continuously sealed at the top of the seam, a sealant discontinuity that creates a vulnerable opportunity for roof leaks. In contrast, the 138T & 238T Symmetrical Systems each have a seam in the form of a “T” with two beads of continuous factory-applied sealant. Once installed, this two-piece design provides an uninterrupted seal at the top of the seam, ensuring there will be no break in the sealant at the clips. For further prevention of leaks, the symmetrical panel design allows installers to work around roof penetrations in order to secure a weather-tight curb solution as well.
Both Symmetrical Systems are composed of a two-piece mechanically seamed standing seam roof panel with a 3/8-inch insulating airspace between the deck and panel system. This airspace helps to reduce the transfer of hot or cold air into the building. The entire Symmetrical System works collectively to adjust with the expansion and contraction that is typical of a metal roof as it is exposed to a range of temperatures.
According to the company, the symmetrical design also performs so well in uplift testing that, in many instances, no additional framing is required to meet wind load criteria in a re-roof or retrofit application.
Architectural Building Components is a leading innovator and manufacturer of metal roofing and siding solutions. For more information, see the Web site.
