Choosing a Metal Roof Fastener
Updated: Jan 31, 2022
When it comes time to replace your roof the initial investment is always at the forefront of our minds. Steel is a very cost competitive product but no matter your roof material choice you'll likely still try to find ways to cut costs and unnecessary expenses. While it is certainly wise to do your due diligence in finding cost effective materials it is equally important that you understand exactly what is being quoted so you don't find yourself in trouble in a few years. There are some areas on your roof that you can pinch pennies and cut costs and there are some areas where you should not, but you should still understand the differences when comparing material estimates. In this article we're going to look at the fastener that is used to secure your exposed fastened metal roof. Believe it or not, all fasteners are not the same and the one that you choose to be installed on your roof could make the difference in the durability and longevity of your roof.
Fasteners are a big deal when purchasing a roof, yet not many people give a lot of thought to them. With exposed fastener systems, the fastener (screw) is likely the first area to fail. Many times this is due to poor installation or a sub-par fastener. This is why it's important to understand fastener types when comparing material estimates. There are a number of fastener types that can be used on your metal roof. These days it is almost always a type of screw with a gasket that seals against the panel (an automatic advantage over asphalt shingles which are typically nailed down). The two dominating metal roof screws in the market today are economy screws and Long Life screws. The differences are substantial. Economy screws are typically a carbon steel shank treated with a cadmium alloy and an EPDM washer. This has been the fastener of choice for years and still remains a quality fastener choice for your roof. However, there are a few areas where this fastener proves it age.
1. When installing this fastener it is important to make sure the fastener is secured straight against the panel and not at an angle. Because of the washer design if it is installed at an angle it could leave a gap that would allow moisture to pass to the substrate.
2. Because the washer is not encapsulated it will experience degradation from UV exposure. Over a span of many years (sometimes a decade or longer) this can cause the washer to under-perform or fail.
A better performing alternative is a Long Life fastener like the one shown here. By simply looking at this screw you can tell it has an improved design over it's economy counterpart. Long Life screws build on what economy screws were good at to make a superior exposed fastener.
Long Life screws feature a zinc casting on head and fully enveloping steel shank. This prevents UV exposure from damaging the washer. Speaking of the washer, it also boasts multi-seal washer technology that allows a positive seal even when driven at extreme angles. The thread design is also different. Long Life screws feature high major threads that increase pull-out value meaning these fasteners won't back out as easily as an economy screw will.
No matter your choice in fasteners, it's always important that you the screw is properly installed. A good screw will fail if installed incorrectly. While the Long Life screw removes some of that liability, it is still recommended to follow best practices outlined in the manufacturers install guide (you can find the Best Buy Metals Install Guide here).
To achieve maximum performance and limited maintenance Best Buy Metals recommends using Long Life screws with your exposed fastener metal roof system. Hopefully now you at least know your options and can make a more educated decision when it comes time to buy.