Low Slope Metal Roof Leaking Shed Snow

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.

Low slope metal roof leaking shed snow.

Constructing a new shed roof at the desired pitch is as easy as knowing how to use a speed square. As you probably guessed lower sloped systems don t shed water as quickly as a steep slope roof. Actually when a standing seam metal roof has a leak it is commonly at some type of flashing area. Some of the most common low slope roof problems relate to improper installation or lack of maintenance.

Sunday august 5 2018 the traditional metal roof types such as 5v crimp shown above and corrugated are rated by the manufacturers for use down to a 3 12 pitch three inches of vertical rise for every foot of horizontal run. The flatter profile of low slope roofs means there is greater potential for heavy snow or rain runoff to exceed the shed capacity of the panels. Failed sealant or butyl tape sealants and butyl tape are used to seal out water dirt and other debris that could compromise a metal roof. It is critical that a designer specify enough snow retention devices based on the slope and snow load.

An older roof will naturally experience more problems than a new roof but with regular inspections and ongoing repairs you can greatly extend the life and service of your roof. In country with heavy snow and tough winter days the metal roof minimum slope is recommended to be 1 12. As stated in the. Again we suggest a minimum slope of 1 inch per foot.

Unfortunately it is frequently the contractor not the architect who gets sued when ice dams cause leaks. Both snow retention items are sometime necessary. If these are damaged missing or applied incorrectly leaks could occur. This means that low slope roofs are more susceptible to leaking due to water backing up or not shedding from the roofing system fast enough particularly in a driving rain storm.

Therefore if your roof rises 4 inches over the course of 12 inches of horizontal run then your roof pitch is 4 12. The metal building industry needs to address the issue of low slope roofs in areas where it snows. Remember that pitch is calculated as the height or rise of a roof pitch over 12 inches of horizontal run.