Partial Roof Replacement in Florida: Can You Replace Just One Slope?

What is a partial roof replacement?

A partial roof replacement means tearing off and re-covering one part of your roof, such as a single slope, instead of the whole thing.

A roof is built in sections called slopes or planes. A gable roof has two big ones. A hip roof has four. A partial replacement swaps the roofing on one or two of those sections and leaves the rest alone. The crew removes the old shingles, tile or metal on that section, checks the wood deck underneath, puts down new underlayment (the waterproof layer under the roofing) and flashing (the metal at edges, valleys and walls), and installs the new covering.

It is different from a repair. A repair fixes a small spot: a few shingles, a cracked tile, one flashing joint. It is also different from a full roof replacement, where every section comes off. A partial job sits in between, and the line between the three is set by both your roof's condition and the Florida Building Code.

Partial jobs most often happen after one-sided damage. A tree limb lands on one slope. Lightning hits one corner. A leak has soaked the deck under one valley. Sometimes a homeowner wants to swap the sunniest, most worn slope first and do the rest later. Whether that is smart depends on the numbers in the next sections. If you are still deciding whether your roof is past repair, start with the signs you need a new roof.

When is a partial replacement a bad idea?

It is a poor fit when the rest of the roof is near the end of its life, when the damage is spread across several slopes, or when the 25 percent line would force a full job anyway.

Think of a partial job as a bet that the untouched sections will hold up for a long time. If they are old, you may pay for a second round of crew, dumpster and permit work within a few years. Ask your roofer to tell you plainly how much life the other slopes have left, and see how long roofs last in Florida for the age ranges.

Look at these warning signs before you agree to a partial job:

• Granule loss, curling or cracking across the whole roof, not just the damaged slope.
• Soft or stained decking when the crew opens the first section.
• Damage on three or four sides after a hurricane. At that point you are replacing most of the roof anyway.
• A roof so old that insurance is the next problem. Read what happens when a roof is too old for insurance.
• A tie-in that has to cross a valley or ridge in poor shape. The new section is only as good as what it connects to.

Roof deck problems are the usual surprise. If boards under the old section have rotted, they get replaced, and the crew may find more wood in bad shape once the covering is off. Roof deck damage explains what that looks like.

How does a partial roof replacement get decided and done?

A roofer inspects the whole roof, measures the share being replaced, checks the permit rules, and then replaces the section down to the deck.

1. Inspect the whole roof, not just the damage

   A good estimate starts with every slope, the attic and the flashing. Written photos let you see what the roofer sees. Read what a roof inspection includes.

2. Count the percentage

   Your roofer measures the section against the whole roof, then adds any repairs or replacement from the past 12 months. That total decides whether the 25 percent rule is in play.

3. Check how and when the roof was built

   A roof that was permitted in 2007 or later is treated differently under 553.844(5). Old permit records at your county help.

4. Pull the permit

   Permit rules vary by county. Alachua County, for one, says repairs or replacements under 100 square feet need no permit. In Manatee County, the roofer posts the permit job card at the job and uploads the notice of commencement and nailing affidavit. For contracts over $5,000, Florida Statute 713.135 also requires a copy of the notice of commencement to be filed with the permit authority before the first inspection. See roof permits in Florida.

5. Tear off to the deck

   The old covering comes off the section. Damaged boards are replaced and the deck is nailed to current rules. Florida Statute 553.844(3) says a roof replacement on a site-built single-family home must include secondary water barrier and roof-deck attachment techniques.

6. Install, tie in and pass inspection

   Underlayment, flashing, drip edge and the new covering go on, and the new section is tied into the old at ridges and valleys. The building department inspects dry-in and final.