Residential Metal Roofing Executive Report Marketing, Lead Generation, In-Home Sales, Installation, Referral Maximization

Condensation

Issue #116 | December 12, 2018 | Todd Miller


I hope this finds you well and enjoying a wonderful holiday season. I don’t know about you but, for me, this is both an incredibly joyous time of year and an incredibly busy time. I have to remind myself to “just slow down” from time to time and enjoy the season.

Before we dig into our topic in this issue of the Executive Report, I wanted to say that our next “Let’s Be Frank” conference call will be held on Thursday, December 20, at 11 am Eastern. These calls center on a conversation with Frank Farmer, president of American Metal Roofs, one of the nation’s leading residential metal roofing contractors. Frank is always very open and candid as he discusses the keys to success for his business, and he makes himself available for ongoing support of other contractors through his business Metal Roofing Consultants. Please join us for our free December 20 call by dialing 857-232-0476 at 11 am and entering 332616 when prompted to enter the pass code. “Let’s Be Frank” is always an informative and interesting time – you will not regret dialing in.

Here’s what Frank plans to highlight during the December 20 call:

  • Every call for information from your company needs to be managed. All inquirers need to be sold on the appointment before you agree to set an appointment. Engaging your customer is the key to having meaningful conversations that lead to appointments. By engaging your customer, you remain in control and do not give away unnecessary information. The more information you give away, the more the customer does not need you to visit.
  • Through questioning, you will learn about your customer’s preconceived ideas and feelings. Exposing these feelings will allow you to draw them deeper into a conversation. By asking them questions you will be able to focus the customer on concerns other than price. During this process you will build trust and an urgency to have you out for a visit. You will quickly set up a scenario where you are in control and the customer needs you to visit. Because they need you to visit, they will be home.
  • A quality appointment generates sales and profit while a poorly set appointment breeds sales frustration, high not-at-home rates, and unnecessary expense.

Normally in issues of the Residential Metal Roofing Executive Report, we focus on opportunities and ideas to help your business with marketing, lead generation, appointment setting, and sales – all good things that build the top line for your business. I want to switch it up a bit in this issue though and look at a very important topic that influences your bottom line – how to not set yourself up for installing roofs that will lead to expensive headaches for you and for your customer.

As someone who helps thousands of homeowners each year with their roofing questions and concerns, I can depend upon one thing like clockwork. Every spring and fall, I will field many calls and emails from desperate, scared, and frustrated homeowners who are exclaiming “I had a metal roof installed and now it’s raining in my attic!”

Here are a couple of photos sent to me recently by one of these homeowners.

condensation 1
condensation 2

What frustrates me is that problems like this become a “black eye” for the entire residential metal roofing industry, leading folks to the fear that there is something about metal roofs that creates condensation. In reality, though, these problems are the result of contractors who did not do a good job of discussing and thinking through the project before proceeding.

In the case of these photos, the home was a modular unit with a flat roof originally and the homeowners “paid extra” to solve their ongoing flat roof problems with a metal roof, only to find themselves later in an even worse situation. In this case, warm moist air from inside the structure is driving into the newly-created cavity beneath the metal roof and being trapped there. When the temperatures drop at night and the roof cools, the moisture condenses on the back side of the roofing. Of course, this was not a huge problem in the summer but quickly became a major problem with the changing season.

The concept of what is happening here is really very simple but usually very misunderstood. Most folks assume the moisture that is condensing is from outside moisture. This is because these problems tend to pop up worst in the Spring and Fall when evenings are cool … and also when it tends to be raining a lot.

What’s really happening though is that warm, moisture-laden air that originates inside the living space is trying to drive its way out of the structure toward drier areas and, if it hits a cold surface when doing that, dewpoint Is reached and the moisture condenses. This is very much like sitting that cool glass of lemonade out on the porch on a warm, humid day. No sooner do you bring the glass outside than moisture in the air is condensing on the cool sides of the glass.

This particular homeowner asked me about removing the roof panels and laminating a product called DripStop to the underside of the metal panels and then re-installing the roof. DripStop is a fibrous material designed to hold moisture and allow it to dry rather than condense. While this product works well on large open-air barns, in a tight space like the attic in these photos, it would have been overwhelmed by the moisture and quickly developed mildew and mold.

Each year, I hear from many homeowners who either are in this situation or have heard about this situation and are frightened by it.

There are three primary things that work together to avoid problems like these. I tell folks that, in some cases, you might get by with just two of these things but never will you get by with one or none. To be safe, you really want to have all three. Those three things are:

  1. Insulation and air sealing. Through insulation on top of the ceilings and making sure that there are no air leaks from the living space into the attic, you can keep the warm air from getting into the attic.
  2. A vapor barrier. This will stop the transmission of water vapor from the living space into the attic. This vapor barrier is usually best directly on top of the ceilings and beneath the insulation. Occasionally, folks will ask about placing a vapor barrier beneath the roof deck or roof panels but all that will do is transfer the problem from the underside of the roof to the underside of the vapor barrier.
  3. Ventilation. Good attic ventilation brings in fresh air at the bottom of the attic and uses convective airflow to exhaust it out at the ridge of the roof through exhaust vents. As the air travels through the attic, it picks up moisture and carries it out as well.

So, those are the things that help avoid these problems but, in assessing a project, there are other things to think about as well.

  1. I never suggest a residential metal roof not installed on solid decking. The solid decking helps prevent warm, moist air from reaching the backside of the metal where it will condense. You can get by without decking on large buildings that have a lot of air exchange going on but that is not the case with a home. Also, large buildings by nature, unless they include animal confinement, tend to have lower ambient humidity levels. (By the way – another common mistake – underlayment should always be installed on top of the roof deck prior to the metal roof.)
  2. This condensation can occur on homes with decking as well. What we usually see is that, in some cases, the homes were already very close to having a condensation issue and the metal roof dropped the temperature of the roof deck enough to cause condensation where it did not occur before. In essence, the metal roof becomes the “straw that breaks the camel’s back.” If you suspect this could be the case on a home, use a smoke pen or machine to check for airflow in the attic and also check moisture levels of the insulation and lumber in the attic. No air movement and high moisture levels indicate a potential problem. The answer is often to increase ventilation in the attic.
  3. Older homes that are not very airtight tend to allow a lot of moisture to escape through the walls and windows. Additionally, we create a lot more moisture inside of older homes than we did when they were first built, through increased amounts of bathing, laundry, cooking, etc. If you’re working on an older home and it is perceived that at some point the owners may replace the windows, add siding and house wrap, and do other things to make the home “tighter,” then be aware that, once those things are done, more moisture will migrate into the attic. Better off to prepare for that eventuality now!
  4. In extreme cases, getting the metal roof up off of the roof deck can be helpful and not drop the roof deck as cool. Various metal shingle products naturally have this helpful airgap between the metal and the roofdeck. Some clip-fastened standing seam products have clips that lift the metal off of the deck a bit. In other cases, some metal roofs can be installed on battens though I caution going that direction. Battens make roofs harder to walk and also less wind resistant. They also can cause gutters to need to be raised and also interfere with dormer windows and other roof protrusions.
  5. Another “worst case scenario” answer is to spray closed cell urethane foam to the underside of the roof deck. This isolates the roof deck from moisture while also having insulating properties. This sort of “hot roof” is being done with some new construction and works well. For retrofit, it is a little trickier and requires someone skilled at spraying foam insulation.

Residential metal roofing is a great and growing industry. But the contractors selling these jobs must do the work to help protect the industry from problem jobs like those shown in the photos.

Thank you, as always, for being a faithful reader. Please accept my best wishes for a blessed Christmas and a wonderful New Year. Please email me or give me a call at 1-800-543-8938 ext 201 whenever I can help you.

todd Miller

has spent his entire career in the metal building products manufacturing industry. He is president of Isaiah Industries, an organization recognized as one of the world’s leading metal roofing manufacturers. Todd is currently Vice President of the MRA (Metal Roofing Association) and a Past Chair of MCA (Metal Construction Association). Through his website, he strives to raise the bar on standards and practices to provide property owners with the best possible products for successful roofing projects.

You may pull quotes from this article provided you include a link back to the original article on this site. You may not reprint this full article, or even a significant amount of the article, without explicit permission. To gain permission, click here.

2 responses to “Condensation”

  1. Alex says:

    Hi Todd, i am glad to read your great article and wish we could be good contacts in business. We are a condensation control solution provider. We make similar products to Dripstop.
    In your article, “This particular homeowner asked me about removing the roof panels and laminating a product called DripStop to the underside of the metal panels and then re-installing the roof. DripStop is a fibrous material designed to hold moisture and allow it to dry rather than condense. While this product works well on large open-air barns, in a tight space like the attic in these photos, it would have been overwhelmed by the moisture and quickly developed mildew and mold. I am not totally agree with you.
    If the felt is thick enough keep welll ventilated in the house. Issues will be sorted .
    I am happy to discuss any questions with you and we can do some testing together maybe.

    • Todd Miller says:

      Thanks Alex. I frequently make recommendations for DripStop but this particular home was a very bad situation. Very small tight attic and absolutely no intake or exhaust vents … and with little opportunity to add any. Definitely a worst case scenario. If DripStop (or similar) will work in situations like that, I do want to know. It just does not seem fathomable to me that it could possibly work. Feel free to email me your contact information and we can connect further. In any event, it would be great to know you and be able potentially to make referrals to your firm. Thanks for reaching out. My email is todd@asktoddmiller.com

Leave a Reply

Your email address will not be published. Required fields are marked *