Racking vs. Stair-Step Shingle Installation: Why It Causes Leaks

Shingles must be installed in the stair-step method, not the racking method. Manufacturers specifically say not to rack. Here’s why racking causes leaks, what the stair-step method looks like row by row, and how to spot a racked roof from the ground.

What is racking?

Racking means installing shingles straight up the roof in columns instead of stepping them across it. Manufacturers specifically say not to rack.

Why does racking cause leaks?

In our experience, racking creates vertical joint lines straight up and down the roof. Water runs straight down the roof, so it builds up in those shingle joints. Small, repeated buildup becomes a substantial leak.

What do shingle manufacturers say about racking?

Malarkey’s installation instructions put it plainly: “Straight up application of shingles, or racking, is not recommended.” (Malarkey technical bulletin)

GAF’s technical bulletin on racking says the racking method should not be used on laminated (architectural) or designer shingles. GAF also warns that racking often leads to missed nails, which reduces the roof’s wind resistance, and to stress cracks from bending shingles, and that its warranty doesn’t cover blow-off or failure to seal when shingles aren’t installed according to its instructions. (GAF technical bulletin R-123)

GAF allows racking on 3-tab shingles, though not as its preferred method. We don’t install 3-tab shingles at all anymore.

How do you install shingles the stair-step way?

Here’s how we stair-step a roof:

1. Install the starter course.
2. Row 1: start with a full shingle at one end.
3. Row 2: cut 6″ off (on the opposite side from where the shingles butt together).
4. Row 3: cut 12″.
5. Row 4: cut 18″.
6. Row 5: cut 24″.
7. Row 6: cut 30″.
8. Row 7: use the 6″ piece.
9. Then repeat.

Each row is offset from the one below it, so the joints don’t line up straight up the roof.

Can I tell if my roof was racked?

Racking is hard to see on a new roof. As the shingles age, you can clearly see vertical lines from the ground if you know what to look for, and they get more pronounced with age. Never go up on your own roof to check. Leave that to a professional.

How common is racking in the Triad?

Too common. Across High Point, Greensboro and Winston-Salem, we see far too many improperly installed roofs, and racking is one of the reasons. If a leak keeps coming back no matter how many times it’s patched, the way the roof was installed may be the problem. A free roof inspection can tell you.

Can a racked roof be repaired?

We never recommend repairing an improperly installed roof. It keeps leaking because it was installed wrong, and the homeowner ends up calling us back again and again. When a roof was installed wrong, we recommend replacing it. Wondering what that costs? See our Triad roof replacement cost guide.

How do I know whether my roof needs a repair or a replacement?

Age alone doesn’t decide it. We’ve seen 25-year-old roofs that look new and 3-year-old roofs that look 20. Read more about how we assess a roof, and the storm damage signs you can see from the ground: Repair or Replace? / Storm Damage Signs.

Why Statewide Roofing Specialist?

• Founded in 2012, with 10,000+ projects since 2012.
• Well over 1,000 roofs each in High Point, Greensboro and Winston-Salem.
• GAF Master Elite, a certification held by the top 2% of roofing contractors.
• Award-winning, including the Angi Super Service Award (multiple years).
• Open 24/7.

Roofing services across the Triad

Need a second opinion on your roof, or a new roof done right?

• Roof replacement: full tear-off and a complete system, from architectural shingles to standing seam metal.
• Roof repair: when a repair is truly needed and possible.
• Roof inspections and drone roof inspections: free, with the same set of photos every time.
• Emergency roof repair: we’re open 24/7, and our trucks always carry tarps.
• Shingle roofing and metal roofing.
• Custom gutters: we make custom gutters in-house.
• Roof financing through Improvifi.

We serve homeowners throughout the Triad, including High Point, Greensboro, Winston-Salem, Lexington, Kernersville, Jamestown, Thomasville and Clemmons.

Call the office nearest you, 24/7: High Point 336-936-5245, Winston-Salem 336-936-5692, Lexington 336-438-8705.

Think your roof was racked?

Seeing vertical lines on your roof, or a leak that keeps coming back? Stay off the roof and call our High Point office at 336-936-5245 for a free inspection. Inspections are free. There’s a charge only if you want a written inspection report and don’t hire us. If you hire us later, that fee is credited toward your repair or replacement.

Call 336-936-5245

Frequently Asked Questions

What is shingle racking?

Installing shingles straight up the roof in columns instead of stair-stepping them. Manufacturers specifically say not to rack.

Why does racking cause roof leaks?

It creates vertical joint lines straight up and down the roof. Water runs straight down, builds up in those joints, and small, repeated buildup becomes a substantial leak.

What is the stair-step method?

Starting from the starter course, row 1 starts with a full shingle, then each row is cut 6″ more than the last (6″, 12″, 18″, 24″, 30″), row 7 uses the 6″ piece, and the pattern repeats.

Can I see racking from the ground?

It’s hard to see on a new roof. As the shingles age, vertical lines become clearly visible from the ground if you know what to look for, and they get more pronounced with age.

Should a racked roof be repaired or replaced?

We never recommend repairing an improperly installed roof, because it keeps leaking. We recommend replacing it.

Should I climb on my roof to check?

No. Never go up on your own roof. Leave that to a professional.

Do manufacturers allow racking?

Malarkey says racking is not recommended. GAF says the racking method should not be used on laminated (architectural) or designer shingles; it allows racking on 3-tab shingles but not as its preferred method.

Can racking affect my shingle warranty?

It can. GAF’s technical bulletin says its warranty doesn’t cover blow-off or failure to seal when shingles aren’t installed according to its instructions.

Can a roof inspection find racking?

Yes. Our inspections are free. There’s a charge only if you want a written inspection report and don’t hire us, and that fee is credited if you hire us later.