Skip to content
Roofing Wiki mark: a document in a round medallionRoofing WikiFind a roofer

Standard

What is a FORTIFIED roof?

Not a product but a designation: a roof built to a set of installation rules that the insurance industry's research institute has shown keep roofs on in high wind.

Updated September 12, 2026 · Every figure links to its source · Sources

DefinitionStandardAlso called: FORTIFIED Roof designation, IBHS FORTIFIED

FORTIFIED roof — a roof built to the FORTIFIED Roof standard of the Insurance Institute for Business & Home Safety — a set of installation requirements covering the deck's fastening and sealing, the roof edges and the rated roof cover — and verified by an independent evaluator who documents each stage and issues a designation certificate; the standard is published by IBHS as the first of three FORTIFIED levels.

What it requires

IBHS is funded by property insurers and runs a laboratory large enough to put a whole house in front of a bank of fans; the FORTIFIED programme is written from what those tests break first. The Roof level — the one an ordinary re-roof can reach — comes down to four rules:

  1. Hold the edges down. Metal at the eaves and rakes is wider than the code minimum, and the starter course is glued down along its full length, since uplift begins at the perimeter.
  2. Make the deck itself waterproof. Every joint in the sheathing is covered — taped, or lapped with a listed underlayment — so the plywood alone will keep rain out of the rooms below if the covering is torn away.
  3. Nail the deck harder. Ring-shank nails on a closer schedule replace the smooth nails a code roof allows.
  4. Use a covering that has passed a wind test. Shingles must carry the top wind class of their ASTM test; metal panels must have been tested to the pressures of the site; other products to their own listings. A hail option adds an impact class on top.

The IBHS page on the roof standard carries the full list and the products that qualify. Silver and Gold are the next two levels, and they move on from the roof to the openings, the gable ends and the roof-to-wall connections.

Why it matters

What separates a FORTIFIED roof from a well-built one is paperwork of a useful kind. An evaluator, independent of the contractor, photographs the deck before the covering goes on and each stage after, because the sealing and nailing cannot be checked once they are hidden; the designation certificate that results belongs to the house rather than the owner and is the document an insurer asks for. Several Gulf and Atlantic coastal states run grant or premium-credit programmes tied to it; the IBHS wind research pages describe the testing the rules rest on.

None of this replaces the building code. The IRC remains the legal minimum and the permit and inspection still happen; FORTIFIED is a layer on top, with its own checker. The National Roofing Directory's own entry on the FORTIFIED roof covers the programme from the contractor's side, a coastal North Carolina guide to the standard and the state's grant programmes shows how one state has taken it up, and the roofing.codes reference covers which roofing rules apply by storm region.

What it costs and who does it

The extra cost lands as a few lines on a replacement estimate: the deck tape or membrane, the ring-shank nails, the glued starter course and the evaluator's fee. It cannot be bought separately, because the deck has to be exposed. The contractor should be one who has completed the designation before and knows to schedule the evaluator ahead of the strip; IBHS and the state programmes publish lists of them, and the directory's storm-damage repair guide explains why a roof opened by a storm is the usual occasion.

Frequently asked questions

Short answers; the sections above carry the detail and the sources.

Is a FORTIFIED roof a type of shingle?
No. It is a designation for how the whole roof is put on — a waterproofed deck, ring-shank nailing, edges held down — together with a covering that has passed the required wind test. Any product that passes the test can be used.
Can my existing roof be certified as FORTIFIED?
Rarely. The deck sealing and the nail schedule have to be photographed by the evaluator while the sheathing is bare, so the designation is nearly always earned during a replacement rather than added afterwards.
Do insurers give a discount for a FORTIFIED roof?
Many do, and several coastal states pay grants toward the work; how large the credit is depends on the insurer and the policy. Ask your carrier to put its FORTIFIED credit in writing before you pay for the extra steps.
Does FORTIFIED replace the building code?
No. The code stays the legal minimum and the permit and inspection still apply; FORTIFIED is a further set of requirements checked by its own evaluator.

See also

Next step

Find a roofer who does this

A FORTIFIED job needs a roofer who has done one before and will book the evaluator before the tear-off. The directory lists roofing contractors by state and city.

Find a roofer for a FORTIFIED re-roof

Sources

  1. FORTIFIED Roof: requirements and rated roof covers — Insurance Institute for Business & Home Safety (IBHS)
  2. FORTIFIED Home — Insurance Institute for Business & Home Safety (IBHS)
  3. Wind research — Insurance Institute for Business & Home Safety (IBHS)