Minimum slope for metal roof

[sidney alstad]

Came across this metal roof over a deck today. Metal roof does not contact gable roof of manufactured home, but I am wondering if that changes the requirement for minimum slope. Also what is the minimum slope for a metal roof?

[Matt Fellman]

Realistically, any more than 1/4" per foot would okay at all but the most windy times. Since it's just over a deck if it had at least that much I probably wouldn't comment. I've built many of those patio covers over the years (it rains a lot in Oregon :) ) and they've been fine. Realistically, I slope them more than the bare minimum.

As for the bare minimum for a metal roof over a house, I'm not sure but I'd bet someone here will know. A standard standing seam metal roof would have to be good down to at least 2:12 I'd think.

[BARRY ADAIR]

this site is a good source for many roof covering types

Metal panel roof systems for low-slope applications | NRCA National Roofing Contractors Association (http://www.nrca.net/consumer/types/metal.aspx)

[Jerry Peck]

Most metal roof panels call for a minimum 4/12 slope.

[Harry Janssen]

Most any type of roof covering,recommends a 4/12 pitch,in order to be effective.

[W. Craig McDougald]

While I was a commercial roof estimator, I saw specifications for metal roofs with slopes as low as 3/8" per foot, approved by the Manufacturer.

Mueller currently accepts 1/2"/12 for "R" panels and 1"/12 for "U" panels, one layer underlayment; no underlayment on lath.

Their CF panel ("snap-lock" type Standing seam) and AP panel both require 3/12, same underlayment requirements as above.

Mueller, Inc. - Downloads (http://www.muellerinc.com/downloads/index.php)

Hope this helps