Roof System No Purlins

Roof hugger retrofit sub purlins are zee shaped structural members that are typically 10 to 12 feet in length.

Roof system no purlins.

For new construction florida building code does not require the use of a purlin system and some profiles like our tcm loc panel does not require use of purlins. Standard gage are generally used for roofing. Numbers 20 and 22 u s. Purlins traditionally support the roof deck cladding sheeting and are in turn supported by the principal rafters steel beams etc.

Onto the current decking and then installing the new roof to those. The purpose of the purlins is to provide a solid foundation for the metal roofing panels and trim to be screwed to. I am getting two different stories from contractors regarding purlins v s. A common arrangement is a rafter and purlin system which combines purlins and rafters.

In the past the majority of roof structures were of wooden construction but over the past 15 to 20 years there has been a vast shift away from wood to metal mainly steel roof construction. The spacing of purlins on roofs and girts on wall is usually 4 to 6 ft. When channels are used the ridge purlin is placed as close to the peak of the truss as possible in order to shorten the connection to the purlin on the opposite side of the centerline. They are made from 16 ga 0 060 min 50 ksi structural grade g 90 galvanized steel and specifically notched to fit over the ribs of the existing metal roof panels.

I have the option of installing the new roof directly to the existing deck or installing new decking if need be or installing 1x4 purlins 2 ft. Modern metal roofs are expected to last 30 years or longer. While metal roofing doesn t require plywood underlayment there are circumstances in which you may wish to install plywood to anticipate future roofing needs or to offer additional soundproofing.