Deciding to upgrade your home with a sleek, durable roof is a major flex. But once you start looking at the details of metal roofing, you might find yourself staring at a pile of accessories and wondering what’s actually necessary. One of the most common questions homeowners ask is, “Do I need closure strips for metal roofing?”
Think of these strips as the unsung heroes of your roof. While the roofing panels do the heavy lifting, these small components act like the seal on a high-end cooler. They keep the good stuff in and the bad stuff out. If you want a roof that doesn’t just look sharp but actually performs when the weather gets wild, you need to know how these work.
What Closure Strips Are and How They Work
At their core, closure strips are specifically shaped pieces of material designed to fill the gaps created by the profile of corrugated metal or ribbed metal roofing panels. Because metal panels aren’t flat they have ridges and valleys for strength and drainage there are naturally open spots where the panel meets a flat surface like a ridge cap or eave.
These strips act as a gasket. They fit snugly into those “ribs” to create a tight seal. Without them, your metal roof would essentially have a series of small tunnels leading directly into your attic space or onto your roof deck. They work by compressing under the weight of the trim or panels, ensuring that nothing gets through those gaps that shouldn’t be there.
Types of Closure Strips Explained
Not all seals are created equal. Depending on where they go on your home, you’ll encounter two main types:
- Outside Closure Strips for Metal Roofing: These are used on top of the panels, usually under the ridge cap. They follow the contour of the upper side of the metal.
- Inside Closure Strips: These go underneath the panels at the eave (the edge of the roof). They fill the gaps between the roof deck and the bottom of the corrugated ribs.
In terms of material, foam closure strips are the standard. These metal roof foam closure strips are typically made from a high-density, closed-cell polyethylene or EPDM. They are tough, flexible, and UV-resistant. Some are “solid,” meaning they block everything, while others are “vented,” allowing air to circulate while still blocking debris and critters.
When Closure Strips Are Necessary for Your Metal Roof
So, do I need closure strips for metal roofing every single time? Generally, the answer is a resounding yes. If you live in an area with any kind of weather which is everywherethey are a necessity.
They are crucial when:
- Water Infiltration is a Risk: Wind-driven rain can easily get pushed up under a ridge cap. Closure strips stop that water from entering your structure.
- You Have a Heated Space: If the building is a home or a finished shop, you need that airtight seal to maintain energy efficiency.
- The Slope is Low: On lower-pitched roofs, water moves slower and is more likely to find its way into gaps through capillary action.
Do Closure Strips Affect Roof Longevity?
Absolutely. A metal roof is famous for lasting 50+ years, but the structure underneath it isn’t always as resilient. If moisture constantly seeps through the gaps in your roofing panels, it leads to rot in the wood decking and rust on the underside of the metal.
By keeping the interior of the system dry, metal roof closure strips prevent the slow decay that often goes unnoticed until it’s a massive problem. They protect your investment. Think of it as the difference between a waterproof jacket and one with a broken zipper; both might look good, but only one keeps you dry in a storm.
How Closure Strips Improve Weather Resistance
The US weather can be unpredictable, from coastal humidity to Midwest snowstorms. Closure strips provide a formidable defense against the elements:
- Wind Protection: During high-wind events, air pressure can build up under the metal panels. These strips help equalize that pressure and prevent the wind from “catching” the edges of the metal.
- Snow Blockage: In colder climates, fine snow (powder) can be blown into tiny gaps. This snow eventually melts, causing leaks inside the attic. Foam closures block the entry point entirely.
- Debris Prevention: Leaves, pine needles, and dust love to collect in those gaps. Over time, damp debris against metal leads to corrosion. Strips keep the channels clear.
How to Choose the Right Closure Strip for Your Roof
You can’t just grab any random foam and hope for the best. To get the right fit, you need to match the strip to your specific panel profile. Whether you are using R-Panel, U-Panel, or a standard corrugated style, the “teeth” of the closure strip must match the height and spacing of your strips and ribs perfectly.
You also need to decide between vented and non-vented options. If your roof relies on ridge ventilation to let the attic breathe, you’ll want vented foam closure strips for metal roofing. If you have other ventilation methods (like gable vents) or are sealing the eave, solid closures are usually the way to go. Check out our high-quality metal roofing products to see the various components that build a complete system.
Maintenance Tips for Metal Roof Closure Strips
While these components are durable, they aren’t immortal. Over a few decades, foam can degrade or be damaged by particularly persistent pests.
- Visual Checks: Every couple of years, take a look at your ridge caps and eaves. If you see foam sticking out or notice gaps where the foam has compressed too much, it might be time for a refresh.
- Check for Light: If you have access to your attic, head up there on a sunny day and turn off the lights. If you see daylight peeking through the ridges of your metal roofing, your closures have failed.
- Clear the Gutters: Keeping your eaves clear of debris ensures that water doesn’t back up and sit against your inside closure strips, which helps them last longer.
Frequently Asked Questions
1. What do closure strips do on a metal roof?
They seal the gaps between the metal panels and the roof trim. This prevents water, wind, insects, and debris from getting under the metal and damaging the structure.
2. Are closure strips required for all metal roofs?
While technically optional for some open-air structures like carports, they are highly recommended for any residential or enclosed building to ensure weatherproofing and longevity.
3. Can closure strips reduce roof noise?
Yes! Noise reduction is a hidden perk. By creating a snug fit and cushioning the space between the panel and the trim, they reduce “chatter” or rattling during high winds.
4. Do closure strips help with pests?
Definitely. Wasps, bees, and rodents see those metal ribs as a “Welcome” sign. Closure strips act as a physical barrier that keeps the critters out of your attic.
5. How long do closure strips last?
High-quality foam closures typically last 20 to 30 years, depending on the local climate and UV exposure.
Conclusion
Getting your roof right means paying attention to the small things. While the big metal roofing panels get all the glory, the closure strips do the dirty work of keeping your home dry, quiet, and pest-free. If you are planning a project, don’t skip this step it’s the secret to a professional, long-lasting finish.
Ready to make sure your next project has everything it needs? Explore our metal roofing services to see how we can help you get the job done right.