Roofing
Can a Roof Be Tornado-Proof? What FORTIFIED Means
No roof is tornado-proof. The FORTIFIED program itself says "no home is 100% 'hurricane-proof,' 'tornado-proof' or even 'stormproof.'" What you can do is build a roof that holds up far better in the weaker tornadoes and straight-line winds that hit most often. The Insurance Institute for Business & Home Safety (IBHS) says its FORTIFIED method has held up to winds up to 130 mph and even EF-2 tornadoes in lab tests and field studies after storms.
If you are replacing your roof this year, this is worth a look. Here is what FORTIFIED is, what it changes on your roof, what it costs, and where its limits are.
How strong is a tornado on the EF scale?
Tornadoes are rated on the Enhanced Fujita (EF) scale. The rating comes from the damage a tornado leaves, so the wind speeds are estimates. This table is from the NOAA Storm Prediction Center.
| Rating | Estimated wind speed |
|---|---|
| EF0 | 65 to 85 mph |
| EF1 | 86 to 110 mph |
| EF2 | 111 to 135 mph |
| EF3 | 136 to 165 mph |
| EF4 | 166 to 200 mph |
| EF5 | Over 200 mph |
A stronger roof can make a real difference in an EF0 or EF1, and IBHS says FORTIFIED homes have handled EF-2s. At EF3 and above, no roofing method keeps a house intact. For those storms, your plan is about keeping people safe, not the roof.
What is a FORTIFIED Roof?
FORTIFIED is a program run by IBHS. The FORTIFIED FAQ calls it "a voluntary construction and re-roofing Program designed to strengthen homes" against severe weather. It has three levels: Roof, Silver, and Gold. A FORTIFIED Roof is the base of every level.
It is not a brand of shingle. It is a set of installation rules, checked by an outside evaluator.
What does a FORTIFIED Roof require?
The FORTIFIED Roof page lists these main parts:
- A sealed roof deck. The seams between the roof boards are sealed. If wind tears shingles off, rain has a much harder time getting into the attic. FORTIFIED says sealing can cut water coming in "by up to 95%."
- Ring-shank nails in an enhanced pattern. Ring-shank nails have ridges that grip the wood. FORTIFIED says they "nearly double" the roof deck's strength against wind.
- Stronger edges. A wider drip edge and a fully adhered starter strip. Wind usually starts peeling a roof at the edges.
- A tested roof covering. Asphalt shingles must meet ASTM D7158 Class H or the listed alternative. Our guide to shingle wind ratings explains those classes.
- An optional hail upgrade. Shingles rated Good or Excellent in IBHS hail testing. FORTIFIED says these protect against hail up to 2 inches in diameter.
Some common shingles can be used to meet parts of these rules. GAF, for example, says its Timberline HDZ shingle "can be used to comply with certain FORTIFIED Roof requirements" on its product page. The shingle alone does not make a roof FORTIFIED. The deck, nails, and edges do most of the work.
How does a roof get a FORTIFIED designation?
The FAQ spells out the steps:
- A certified roofer installs it. Each FORTIFIED Roof "must be installed by a certified FORTIFIED Roofing Contractor."
- An evaluator documents it. You work with a FORTIFIED Evaluator who documents and checks the work as it happens. IBHS describes this as "an intensive inspection by an independent, third-party evaluator" on its Home Upgrades page.
- IBHS issues the designation. It reviews the evaluator's records and issues a certificate.
- It lasts five years. Certificates "expire five years from the date they were issued." A new inspection renews it.
The evaluator documents the work while it happens, including the deck before shingles cover it. You cannot add a designation to a finished roof. Plan it before the tear-off.
If you want the designation, ask any roofer you talk to for proof of FORTIFIED certification. Do not take a sales sheet's word for it.
How much does a FORTIFIED Roof cost?
FORTIFIED is honest that it adds cost. Its FAQ says that for re-roofing, "the cost increase is typically between $1,000 and $3,000" for a 2,000-square-foot home. The evaluator's fee is extra.
For scale, a standard asphalt roof replacement on a typical Cincinnati home often runs $8,000 to $20,000. The upgrade is a real add, but not a doubling.
Will a FORTIFIED Roof lower my insurance?
Maybe. The FAQ says a designation "may qualify you for financial incentives like, insurance discounts." When asked whether insurers offer them, it answers, "Sometimes yes. Please contact your agent for more information." It names states such as Alabama, Louisiana, North Carolina, Oklahoma, and Mississippi where some insurers offer FORTIFIED endorsements. Ohio is not named.
Call your agent before you decide. Ask whether your company gives any credit for a FORTIFIED designation, and get the answer in writing.
The Ohio Department of Insurance notes that standard home policies generally cover wind and tornado damage after deductibles are met. A stronger roof does not change that. It lowers the odds you need to file.
Can I get the same upgrades without the designation?
Yes. Many of these steps can go into any roof replacement:
- Ring-shank nails for the decking.
- Sealed deck seams or a full deck membrane.
- Starter strips at the eaves and the rakes.
- Shingles labeled ASTM D7158 Class H.
- The manufacturer's high-wind nailing pattern.
You get much of the strength. You do not get the outside inspection, the certificate, or any discount tied to it. If an insurance credit matters to you, go the full FORTIFIED route.
What else fails in a tornado besides the roof?
The garage door. IBHS calls it "one of the most vulnerable parts of the home during a tornado because it is a large opening." IBHS says high winds can push a garage door inward, "allowing pressure to build inside the garage." It also says that before 2006 there were no wind-rated door rules for homes outside Florida. Look for a wind rating label on yours.
Trees. Limbs over the roof become debris. Keep them trimmed back.
People. A roof is property. IBHS says a tornado safe room "is designed to provide the best protection from winds up to 250 mph." If you do not have one, know your shelter spot before a warning. Our West Chester tornado prep guide covers where to shelter and what to do after.
How Shamrock can help
We replace roofs across Northern Cincinnati, and we will walk you through which wind upgrades fit your home and budget. If you want a FORTIFIED designation, we will tell you plainly what that takes and help you plan it before the tear-off. Start with a free roof inspection and estimate, or read about our roofing services.
FAQ
Can an existing roof become FORTIFIED? Not as it sits. The evaluator must document the deck, nails, and edges during installation. It is done at re-roofing time.
Does FORTIFIED protect against hail? Only with the optional hail upgrade, which uses shingles rated Good or Excellent by IBHS. The base FORTIFIED Roof is aimed at wind and rain.
Is a metal roof tornado-proof? No. FORTIFIED allows metal roofs, but they must be tested for the wind pressures at your site. Any roof can fail in a strong tornado.
What should I do first after a tornado damages my roof? Get everyone safe and away from downed lines. Then photograph the damage and cover openings if it is safe. Our first 48 hours guide has the full checklist.