Just wanted your opinions on the chart provided by Nachi. According to the chart, metal roofs only have 17-20 years of life expectancy in Florida, and based on the roofs I’ve seen in Florida, they seem to last significantly longer than that usually.
Now I know this chart is only a guideline but do you think it is way off or have I just been lucky in noticing no real deficiencies in metal roofs 25-30 years old already?
But I’m only worried about Florida. Are they saying that it is likely to be damage in 17-20 due to weather conditions such as hurricanes, hail, etc.
Or are they saying it simply deteriorates in that time frame due to the sun, heat, etc.?
In terms of the 4PT inspection we have in Florida. If I see a metal roof that is 20 years old and looks fine, I lean towards giving it 10-15 more years rather than 0 according to Nachi’s guidelines in the above link.
As I said, that chart needs to be updated. And, yes, in Florida.
The average life expactancy is under “normal” conditions. Hurricanes, tornadoes, etc…may shorten that lifespan…
From personal experience, 25-50. Weather is not the only factor. Quality of materials and installation is also a big part of the equation. Screw-down ribbed panels tend to have more problems than standing seam. Cheap imported steel will rust sooner. If the screw tailings are not removed upon installation, then pockmarks of rust will progress into deterioration or perforation. Finally, some fastener gaskets deteriorate more quickly than others.
Ultimately, keep the expected life broad and conservative. (by the way, people selling the metal roofs will tell you they last 150 years, lol)
Not sure how this answered my question… Did the roof fly off because of poor installation, or was it because it was 20 years old and deteriorated? That would answer my question.
Honestly, it doesn’t matter.
IMO, given the conditions at the time, a NEW, perfectly installed metal roof will incur damage also.
The point of the chart YOU posted is that Florida and coastal areas are subject to damaging conditions that will affect ALL roofing types, whether new or older age and any condition, and having to go through these climatic events on nearly an annual basis, shortens it’s expected lifespan from repeated exposure.
A hurricane doesn’t give a rats ass about the age and condition of a material. Damage will happen, regardless!!
I guess we are having a miscommunication problem perhaps on my end, for which I apologize if that’s the case…
I’m aware that the chart is stating the climate events in Florida negatively effect the roof’s life expectancy. My question was if it seemed accurate that it would effect the expectancy by 23 - 60 years according the chart YOU posted.
I take all of those factors into consideration when filling it out. I was just curious as to whether other people thought 17-20 life expectancy was accurate or not for Florida. (I’m assuming they made those values with the assumption the directed maintenance and care were done throughout the 17-20 years.)
Brian has it right. The quality of materials is very important.
Here in Hawaii, Rust is the major issue. The lowest edge starts to bubble in 3-5 years but the rust does not break through the surface for 15-25 years. How close to the ocean makes a big difference with the salt in the air from breaking waves. Even a mile inland is close enough to make a difference. I always tell my clients that normal maintenance is to re-screw (replace all the screws) the metal roofs every 20 years because the screw heads will be rusting by then and even a little rust will breed more rust. By 15 years many of the gaskets on the cheap screws are sun damaged and can start leaking.
I have found that all the cut edges (like in the valleys) should be painted when installed. Even a spray can of clear enamel is enough to make a big difference with rust prevention.
Bottom line a good quality, well maintained metal roof should last 50 years. It will probably be painted at 30 years to keep it looking nice.
So in conclusion, you would say that 30-50 years in Florida? (Assuming regular maintenance is performed) Which is what I would agree with, rather than 17-20 per the estimate Nachi provides.
I’m not sure I would rely on everything interNACHI puts in their information material. I surely wouldn’t be putting tables like that in my reports. If you really question it that much, ask @bgromicko1 as to it’s accuracy and if if should be modified or update in his material.
Wow… So you’re just gonna keep pushing the issue until someone says what you want to hear?
If not Internachi, then who? The truth hurts sometimes. Do you want to be the one dealing with the pain when a roof fails or gets damaged, and your fear of disclosing the facts bites you in the ass??
@jjonas No… I’m happy to hear someone say they think 17-20 years is accurate. I just haven’t seen someone outright say that. Which is why my follow up questions are asking to be precise. Didn’t realize some people (you) would have such a strong opinion and not give a yes or no answer.
