5 Most Common Metal Roofing Mistakes

The Most Common Metal Roofing Installation Mistakes and Issues

So you are considering a metal roof for your home, you get on the internet to find and learn about the various roofing companies and arrange to get bids. Several of the roofing contractors are now coming by and providing you with bids for the installation of a new metal roof. Now, as you review the bids, you wonder why you are seeing such a big difference from one company to another for the cost of the roof installation. You don’t want to make a mistake with roof issues of a metal roof that has been poorly installed .

A metal roof is a metal roof right? So why would there be so much of a difference in the price from one company to another? With a project like this, it is one that you only want to do only once and have it done correctly because even subtle installation mistakes can cause issues in the long run. Please read the warnings and metal roofing advice below to know what to do to ensure you have a great roof, the first time, saving yourself time money and headaches!

1 – Metal Roofing Batches Color Issues

Standing Seam Galvalume Metal Roof Color Batch Installation Issue

Standing Seam Galvalume Metal Roof Color Batch Installation Issue

This photo is a commercial business located in Spring Texas near The Woodlands Texas south border of town.

As a historical constant, commercial builders will, almost 99% of the time, choose to go with the lowest bidder on their projects in order to maximize the profits on their building project. You can see in the photo to the right, a standing seam unpainted called Galvalume Roofing product was used for this metal roofing system that is only a few years old.

When studying the photo, it is quite obvious to see the color differences indicating where the installers used product from two different batches of material. It is quite common practice for roofing contractors to use leftover material from previous jobs where the material was not purchased together and ends up coming from different batches with color variations.

What has happened is that over time this creates a problem as these two different batches will weather differently causing the effect you can see in the photo. Can you imagine, paying a lot of money for a new roof, only to have revealed mismatched colors. This is not something you will notice when the roof is newly installed, it will look beautiful until down the road exposure to the elements and time that different batches were installed on your roof. The roofing crew knows they are from different lots and were purchased at different times, but you will not see evidence of the roofing color mismatch till a few years later long after the crew is gone and the check has been cashed.

2- Voiding The Warranty

There are many things a roofing company who installs a metal roof can do that will inadvertently void the roofing warranty. Here is a quick list of some items to be aware of and watch out for that may void your warranty on the new roof you paid good money for: The installation of the panels, jagged cut edges that are not sealed (painted), fasteners that were driven to tight, wrong sealant used around protrusions, improper underlayment, furring strips spaced out to far, crinkles on the panel from walking in the unsupported areas, unsealed scratches from installation crews just to name a few.

3 – Fasteners Rusting and or Backing Out

Metal Roofing Fasteners Backing Out

Metal Roofing Fasteners Backing Out

This is by far one of the most common issues that can lead to leaks as well as constant maintenance issues of your metal roof system.

Something to keep in mind, a metal roof standing seam panel with the hot Texas blazing sun beating on it will move at a different rate than the wood furring strip underneath the panel that it is attached to.

This becomes a BIG problem due to the fact that so many of the roofing crews who simply drive the screw fasteners from the outer top side of the panel directly down into the wood furring strip below. This is a BIG NO, NO! The better way to install standing seam panels is with a hurricane wind resistant Z-purlin which is made of 20 gauge  steel that will move at the same rate as the metal panel above it. The metal roofing is then fastened with the screws through the Z-purlin (support), down into your roof’s decking. This prevents the fasteners from backing out and causing the holes to wallow (made bigger) and more elongated holes in the panels that were smaller when the roof panel was initially installed.

4 – Oil Canning (wavy panel)

A Classic Issue Of A Oil Canning Metal Roof

A Classic Issue Of A Oil Canning Metal Roof

This image at the right shows the dreaded look of a wavy metal roof, no one likes to see their roof doing this! Nearly 100% of the time, this problem is due to the installer using a thin standing seam panel of 26 gauge or thinner.

The contractors will often choose to use these thinner (26 gauge) roofing panels in order to increase job profits because the cost of these panels are less for the roofing contractor. Additionally, these panels are lighter in weight so much easier for the roofing crews to install, screw thorough, crimp, etc. This is also a “non striated” (no small ribs) in the wide open section of the panel that would also reduce the Oil Canning effect.

This BIG drawback of using the thinner 26 gauge sheet metal is the dreaded oil canning effect that can occur when our hot summer Texas sun starts beating down on the roofing panels. This thinner panel often looks good in the cooler months, but quickly becomes quite a different story as the summertime heat sets in as many homeowners have reported this across the country. The solution is to upgrade to a 24 gauge anti oil canning “striated” standing seam roofing metal roofing panel, this instantly corrects 99% of the slightly oil canning effects and issues.

5 – Choosing the lowest bidder (estimate) for roof installations

This is the most self-explanatory of the 5 most common installation and estimate mistakes. This happens to be the most common mistake we see property owners making during the selection process. Commercial business owners and homeowners alike often get at least three bids for their roofing project.

One of the ways we are identifying this method is that we are being asked more and more often to email a bid or just leave it in the mailbox. When a prospective customer looks at the estimate, the first thing that they often look at is the price. In reality, this is the quickest way to overlook the quality and details of the installation that will be used for your new metal roofing project.

Keep in mind the importance of meeting with and interviewing each and every roofing contractor face-to-face regardless if you are paying in cash or financing your new metal roof, it is still your hard earned money. In my opinion, by personally meeting (interviewing) with them allows you to get a sense of their Professionalism, knowledge and installation techniques allowing you to learn how they plan to install your new metal roofing system as well as meeting the contractor in person.

Another word of advice, be sure to ask for a current, verifiable insurance certificate and some references to their previous work as well. The quality of their installation often influences the roofing cost as the saying goes, “You Get What You Pay For”. If you are considering a Metal Roof over and Asphalt Roof, you should check out this like to see the differences between the two.

Texas Home Exteriors Inc.


Metal Galvalume Roofing Color Issues

Metal Galvalume Roofing Color Issues As Indicated By Arrows

PS: Take a close look at this standing seam metal roof (mistake) where they apparently used different batches of galvalume to save money.

So not worth the money they saved to forever have it look like this, click on the photo enlarge. Thank You for reading this 5 most common metal roofing mistakes & issues post. 

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39 Responses to 5 Most Common Metal Roofing Mistakes

  1. Zach Thalman says:

    This doesn’t seem like a problem with the roof as much as it is a problem with the roofing contractors. I would just make sure that the roofing contractors have the same color for the roof. I have seen a lot of metal roofs with all sort of different colors instead of just the gray in the picture. The varying in color may depend on what color you want the roof as well.

    • Greg Kapitan says:

      Zach, great reply and point! I will agree with you that it can most definitely be the metal roofing contractors that a homeowner are dealing with as well as the product that they are installing. Thanks again for your reply!

  2. Chester says:

    Thanks for your marvelous posting! I really enjoyed reading it, you’re a great author.I will make sure to bookmark your roofing blog and will often come back at some point.


    • Greg Kapitan says:

      Thanks Chester1 A lot of folks are not aware about the most common metal roofing mistakes.

      • Monica Adams says:

        Please help! I’m not even in your state. Doing research on why our 24 gauge standing seam with pencil rib metal roof so severely oil canned. The builder nor the metal company want to take responsibility. It is so frustrating! I know the wood sheeting was installed and then rained on for 2 weeks before the metal went up.

  3. Doreatha Molesworth says:

    I live in Spring TX and was considering a new metal roof. Then I Googled on the net to get some more information and came across your article about some issues that are or possibly can be associated with metal roofing. What do you know about cell phone reception issues in the Spring TX area should we decide to install a metal roof? Will I be able to get reception form my provider Verizon? Dor.

    • Greg Kapitan says:

      Dor. That is a great question as there are many factors involved like, how big is your roof surface area, one or two story home, how close is the nearest cell phone tower, what part of Spring Texas are you in and is your home on a hill?

    • LIZO says:



  4. Michael Lee says:

    Wow, i did not realize how many problems could arise with metal roofing! Thank you for taking the time to address how to deal with the installation of metal roofing panels, as I would not have thought of some of these issues trying to DIY the job myself. If I ever do actually decide to pursue this type of work, this will be a good reference article that I will ave!

    • Greg Kapitan says:


      I read your email and we are glad that you found this post on Common Metal Roofing Mistakes helpful considering that you are a DIY homeowner. Most homeowners like yourself are not aware that their can be many issues associated with metal roofing if it is not installed correctly. The last thing that you want is to have a leak in your new roof. Good luck with your project and thanks again. Greg Kapitan

  5. Trever says:

    This article goes really in depth into metal roofing. I am going to send this link to some of my clients so that they have a better understanding. Hopefully you don’t mind me doing that!
    Thanks Mr. Kapitan.

  6. Ann says:

    I never knew there were so many ways to completely mess up the installation of roofing. I’m guessing that roof installation isn’t all what it’s cracked up to be. When you supposedly install a roof your better off having a professional do it. This article was very helpful when having common mistakes made in your roofing.

  7. Mark Spragg says:

    What are warranty issues when the roofing panels are not lapped correctly?

    • Greg Kapitan says:


      Thanks for your question. If the roofing panels are not lapped correctly many problems can occur such as possible water leaks, buckling and the dreaded oil canning affect. I would think that most metal roofing manufactures will not honor their warranty if their product was not installed correctly. I hope that helps to answer your question? Greg from Texas Home Exteriors

  8. Donna says:

    We are considering a galvalume roof, but we are worried about it showing wear. One contractor we spoke to said that it will start to discolor in about 2 years and will start having black marks in about 10 years. What are your thoughts on the longterm wear and appearance of unpainted galvalume?

    • Greg Kapitan says:


      Thank you for your question as it is a concern for many homeowners and commercial business owners alike. The contractor that you spoke to that gave the information is correct. The galvalume metal roofing panels will weather after some time as some homeowners and business like and consider that a desirable look. The galvalume metal roofing will get more weathered look the longer that it is on a home or building. I hope that this information helps you Donna.

  9. Carl says:

    Better to choose a lowest bidder but have a quality roofing techniques.

    • Greg Kapitan says:


      Thanks for your comment on roofing mistakes. Please explain why it is “better to choose a lowest bidder but have a quality roofing techniques” what did you mean by stating this about roofing?

  10. Ken Adams says:

    Great info. I agree that many homeowners go with the lowest bidder instead of doing research on the roofer, getting referrals and photos of previous work. Its definitely better to go with a creditable, experienced roofer than with the cheapest.
    We are a roofing company offering quality work and free estimates named Joye Roofing in Columbia SC. Look us up!

    • Greg Kapitan says:


      That is so true. It always comes down to the old saying that is true, “you get what you paid for”. The cheap bid and or estimate for roofing is not the best choice. Thanks again Ken!!

  11. Monica Adams says:

    Please help! Severe oil canning! The builder, metal company, or roofers refuse to take responsibility. The underlayment and standing seam metal roof were applied to a wood sheeting that had sat in the cold and rain for two weeks. It looks terrrible. I’m having it inspected tomorrow. It’s 24 gauge and it shouldn’t have happened.

  12. Monica says:

    Update. I had an inspection on my severely oil canned 24 gauge standing seam roof. From what the inspector saw, it looks like it was improperly installed. Still not sure who is responsible, but can it be fixed? If they unfasten it and refasten it the proper way with a foam backer, will the peaks and valleys appear less?

    • Greg Kapitan says:


      We are glad that you did get an inspection for your metal roof. To answer your question, sometimes the foam backer will help smooth out the peaks and valleys. However this is mainly due to roof rafters being high and low. This is mainly a cosmetic visual issue and often will not affect the integrity of the structure.

  13. Paul says:

    Texas home exteriors. Most contractors and homeowners as well do not understand that metal roofing is so much different than non metallic roofing products. Because the metal roofing panels have to expand in the sun, you need to have an understanding of how this product moves. You do not have the same issue with composition shingles that are asphalt based. They are much different indeed

    • texashomeexteriors says:


      You have some really great valid comments here. Roofing contractors and homeowners need to realize that the metal roofing is much different than the traditional composition roofing shingle. Thanks for your comments Paul!

      Greg of THE

  14. Ivy Baker says:

    I have been thinking that I should get a metal roof installed on my home. It is good to know that you need to pay attention to fasteners rusting. It would probably be smart of me to have a roof inspect my roof frequently for things like that.

  15. Ivy Baker says:

    I just moved into a home that has an older roof. I am considering updating it soon. So, I liked what you pointed out about roofing mistakes. I will get at least three bids for the roofing to get done. Thanks for the information.

  16. Jesus Borrego says:

    By reading as it says its galvalume which is some pretty expensive metal as well as copper coat. But i wouldnt be surprised if the metal had arrows and were the drops of another side, so they flipped them over and used them for the other side. It shows 5 continuous panels and 5 more in a pattern. It shows one in the middle of the valley as if its a drop from another side where it was just long enough. Wow, just realized if it a snap lock it should have the female side on the same side anyways which would mean the mistake starts from when the coil was slipped in the machine to make the panel. Maybe they did use a different coil or had a different manufacturer put the coil in different dirrection. Maybe same metal just when metal coil was made was wound up the opposite. Working as an architectural sheet metal roofer for 15 years and worked in many companies. Dont doubt or hate the comment just a thought.

  17. Darrel says:

    Dear Texas Home exteriors,

    I’ve read this roofing post and if I could I wish to suggest to you some interesting things or advice and further information for homeowners. Maybe you could write next articles referring to this metal roofing article with more in depth information. I want to read even more things about home improvement and watch out for mistakes.


  18. Chelsea says:

    I found exactly what I was having a look for here at your site for metal roofing. God Bless you man. Have a nice day. Bye …

  19. Greco says:

    Thank you so much for this information! I actually love the idea of getting metal roofing, I really want something that can last a long time! I will make sure to look out discoloration and ask about it when the time comes. The uniform color and material is really important because, as long as they come from the same batch, they should weather evenly and the maintenance would be the same as well!

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