Pre-manufactured roof curbs are developed to eliminate roof leakage. All roof curbs should be a minimum of 200 mm (8 in.) above the finished roof and should be welded or sheet-screwed to a metal, wood, or tectum deck or to the structural steel. On the concrete roof deck, the RAM setting is the most popular. The curbs are insulated with a 40 mm density of rigid fiberglass installation at the job, which is difficult and more expensive, especially if curbs are canted and pitched.
Pressure-treated nailers are provided not only for receiving the roofing felts but also for eliminating noise transfer. Curbs are manufactured from gauge galvanized or galvalume material and internally reinforced with 25 x 28 mm angles, placed every 610 mm on center for a curb with any dimension of 915 mm or longer. You can get to know more about pre manufactured roof curbs via https://www.quickframes.com/rtu-hvac-support-frames/.
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They can be fabricated to any height or roof pitch with options such as aluminum, stainless steel, burglar bars, wider nailer, and many other custom specifications. A major problem with equipment manufactures' standard roof curbs is that they do not match with many kinds of roof deck situations that are being specified.
The prefabricated roof curb is coordinated not only to match the selected equipment but also with roof construction. Custom Prefabricated Roof Curbs are coordinated and fabricated to fit equipment that is going to be used, not to fit some roof-opening size that has been pre-determined during design as an approximate size.