Roof Purlin Deflection Criteria

Therefore a purlin should be adequately strong to withstand the loads it will encounter during its design life and should not sag in an obvious manner thereby giving the roof sheeting an undulating and or unpleasant appearance.

Roof purlin deflection criteria.

Dead load will be the actual weight of the roof steel and the roof purlins. The cos of the purlin spacing is because the load on the purlins is vertical and the purlin spacing is with the run of the roof. Mean roof height is not greater than 40 feet. Top running crane trc beams.

Floor beams floor joists and floor decking. 3 mezzanine beams and joists. Table r301 7 allowable deflection of structural members. Allowable deflection as an expressed ratio of the clear span.

For sake of discussion we will assume a minimal roof snow load of 20 psf pounds per square foot and a 4 12 roof slope. Other than plaster or gypsum board. Underhung crane uhc beams. Plaster or gypsum board.

Introduction and components roof systems 10 23 eaves beams 24 27 side rail systems 28 53 ancillary items 54 59 load tables 60 78 mezzanine floor systems 79 85. Z section purlins 10 c section trimmer 51 side rails 28 7 metsec uk leaders in the design and manufacture of engineered and bespoke purlin and side rail building solutions. Roof rafters roof joists and roof beams. The attached list of criteria is met.

Monorail crane mr beams. Roof sheathing is at least 7 16 thick oriented strand board or plywood. This post will be focusing on design of steel purlin using cold formed sections. Plaster or gypsum board.

Other than plaster or gypsum board.