Min Roof Slope For A Metal Roof

Most residential metal roofs require at least a 3 12 roof pitch and have no maximum roof pitch.

Min roof slope for a metal roof.

Roofing material or system. The minimum slope for lapped non soldered seam metal roofs with applied lap sealant shall be one half unit vertical in 12 units horizontal 4 percent slope. There are some opinions that standing seam metal roof minimum slope is 12 but it increases the possibility of leaking on the few first days of snow arrival. After that the miimum pitch for metal panels depending on the methods used to join the panels.

This recommendation con flicts with some manufacturers who list 1. That means there is at least 3 of vertical rise to the roof slope for every 12 it goes back horizontally. The minimum pitch for metal roof shingles and lapped non soldered panels is 3 12. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

Standing seam manufactures allow applications of metal coverings on slopes of 12 or even more. In country with heavy snow and tough winter days the metal roof minimum slope is recommended to be 1 12. The pitch is measured in inches of vertical rise per foot of horizontal run and the 5v crimp profile shown above requires a minimum slope of three in twelve or 3 12 3 inches vertically per 12 inches horizontally. You can often see such examples of use over metal decks.

Panels joined with an applied lap sealant can go as low as 12. Speaking about standing seam metal roof slope it is a general and a self evident knowledge that the steeper it is the faster it is for snow rain or drain to come down the roof. The minimum slope for lapped non soldered seam metal roofs without applied lap sealant shall be three units vertical in 12 units horizontal 25 percent slope. Metal roofing shall resist a minimum wind uplift resistance as determined by chapter 16 high velocity hurricane zones for a roof slope of 9 5 degrees 0 0166 rad and a roof mean height of 15.

To get the minimum pitch for a metal roof the vertical rise per foot is divided by the horizontal slope. In 12 0 25 in 12 1 19 built up roof coal tar pitch. 18 43 asphalt shingles with special underlayment requirements 2 in 12. Lap sealants shall be applied in accordance with the approved manufacturer s installation instructions.

9 46 built up roof asphalt. The nrca roofing and waterproofing manual fifth edition states the mini mum slope for structural metal panel roof systems should be 1 2 in 12 2 4 degrees. Most metal roofs will have minimum pitches of three in twelve but this might sometimes go down depending on whether there are special installation procedures issued by the manufacturer regarding that particular roofing material.