Recommended design lower than 3:12 slope

Jeff Seabold
I have designed plenty of metal roofs, but am trying to find a good source on documenting the best practice for the design of a low slope roof. Traditionally, I have recommended on slopes lower than a 3:12 a double locked seam, over ice and water shield. Is there a design manual for metal roofs with a recommendation of design for various slopes? I have a specific situation where a low slope copper roof has a couple 8:12 slate roofs adjacent to it. I suspect that the lower roof was not flashed properly to the slate roof is one problem. I am also seeing that the 2:12 copper roof only has a single lock on the panels. There has been an ongoing leak at this location that we have been asked to help repair. I need some documentation on how to proceed from a best practices standpoint, if that makes sense, to make the recommendation to the client's insurance company. Thanks for any advice you can offer pointing me in the right direction.
Eric Novotny
An informed customer is the Best Customer!
Where is the leak showing in this case? At the intersections of the roofing? A 2:12 single lock would be fine on its own, but when you have water crashing into the side of it like that, you are going to have problems there.
Todd Miller
Isaiah Industries, Inc.
Here is a website where you can download the Metal Roof Installation Manual from metal Construction Association You may also check in with SMACNA. The 2:12 roof really does need a double lock panel ... not saying there ar not other issues afoot but that is a problem to my way of thinking. Thanks for fighting the good fight!

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.

Find a Professional

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Professionals in your area for a free consultation and estimate.