4yr old galvalume

The plastic film is for shipping. They usually ship the panels in crates. The plastic film is to keep the panels from scratching each other and to prevent scratches from unavoidable rooftop traffic during the install. You're supposed to peel the plastic off immediately AFTER the panels have been installed. The corrosion started with the cut edges and was accelerated by the exposure to a salt rich ocean environment in a humid area. The type of paint on the panels could also be a factor. These panels were probably painted with an SMP, not Kynar. Also, there shouldn't be cut edges at the eave anyway. Proper install would have the panels hemmed & hooked to a starter cleat along the eave

I was just in the Bahamas on Thursday. On the pier there were roofs just like that one. My first thought was Way to close to the ocean for painted steel. Salt air will permeate everything. From the looks of the pics. that house in right on the coast and storms will bring salt water in direct contact with the roof.

We have tons of galvalume roofs down been installing them for over 20 years in coastal Louisiana and have never seen corrosion like that on on roofs.I would say that is the exception, not the rule!Average life expectancy of r panel on a metal building here is about 30 to 40 years if installed correctly,usually fails on the z channel or c channel where insulation holds moisture due to A.C. system.I have to ask was this house hit by a hurricane?Was this roof exposed directly to salt water?

Most of the formed panels I have ever worked with have the film removed before they make them. Mostly the flat sheets have the film on them and we have to peel it beforewe install the trim pieces made from them. Never heard of such a thing, but then again, I am not from the Bahama's. How would you not finish peeling it off on the edge? That doesn't make any sense.

Hey Branden. Email me. John

Another roofer here said his opinion is that the rust started because they didn't peel the plastic off some of the folded edges and the plastic covered spots held water and therefore rusted. He claims he's seen it a lot. Its hard for me to believe. Whadda yall tink?

Why was the rust so much worse on just one side of the ridge? Were the panels cut short on top?

Obviously the rust "started" at the cut edges and moved out from their. No doubt it would have failed sooner than later on the rest of the panels.

I can't think of a single good use for galvalume. Yet people keep selling it as a 50yr roof. I'm just doing my best to expose these P.O.S. products. All the customers hear is "metal lasts forever" and everyone in the industry just agrees and deposits their check. There's a building here in nassau, a couple hundred squares, they had to rip it off and replace it with aluminum before it was completed cause it was rusting before they were even finished. That building is a couple miles inland.

I can't think of a single good use for galvalume. Yet people keep selling it as a 50yr roof. I'm just doing my best to expose these P.O.S. products. All the customers hear is "metal lasts forever" and everyone in the industry just agrees and deposits their check.

Isn't galvalume to be kept a minimum of 1,000 ft away from salt water, i.e. the Ocean?

That's why the seams have to be flat-locked with a sealant to imbed the cut edges in.