If you want to know if a gutter installer is a pro or just a guy with a ladder, look at his miters. If you see the heads of hex-screws (zip screws) sticking out of the corners, you’re looking at a failure waiting to happen.
In my 31 years in the business, I’ve held a hard-and-fast rule: Zip screws have no business in your miters, downspouts, guards or end caps.
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The “Snag” Factor
A zip screw might be faster to install, but it leaves a sharp, half-inch “spear” of steel pointing directly into the water flow inside your gutter. This is a magnet for pine needles, oak tassels, and roof grit. Once one leaf snags on that screw, it starts a dam. Standing on the ground looking up at them they are also very unprofessional looking. Before you know it, your “maintenance-free” corner is a compost pile, holding water against your fascia and rot starts to set in.
The Professional Standard: Pop Rivets
If you want a joint that is permanent, leak-proof, and “snag-free,” you use 1/8″ aluminum pop rivets. They provide a low-profile, high-strength connection that stays flush with the metal. When combined with the tripolymer sealant I recommended in my previous post, a riveted miter becomes a single, unified piece of armor for your home.
The 25-Year Workhorse: The Malco Rivet Gun
To do this right, you need a tool that won’t jam when you’re hanging off a corner. I’ve used the exact same Malco Rivet Gun for 25 years. I’ve dropped it 20-30 feet countless times and it just keeps on snapping rivets.
Most cheap rivet guns you find at the big-box stores will snap a mandrel and jam up after ten clicks. The Malco is a different animal. It’s built with heavy-duty steel, but it’s designed to be used with one hand—crucial when you’re holding a miter tight with the other.
It’s outlasted three trucks and countless crews. If you’re building your 5-Year Foundation Shield, don’t cut corners with screws. Get a Malco, get some 1/8″ rivets and #30 drill bits and build a corner that will outlast the roof it’s attached to.
Check out the rest of my Master Gutter Tool Box for the exact professional-grade tools I’ve used for over 20 years.