Roof Replacement in Charleston, SC

When your roof has given all it can, build the next one for Charleston: torn off to the deck, rotted decking replaced, rebuilt to South Carolina’s code and the shingle maker’s instructions. It starts with a free, no-obligation inspection, drone-assisted where it helps, and a straight read on whether you need a replacement.

Roof Replacement and New Roof Installation in Charleston, SC

A roof replacement is a new roof, not a bigger repair. On a Charleston home it means every existing layer comes off down to the wood deck, the deck is checked and repaired where it has gone soft, and a new system goes on, built to the code South Carolina enforces and to the wind design for your address. Big Bear Roofing does this work across the Lowcountry, serving Charleston and the rest of the tri-county: Charleston, Berkeley and Dorchester counties.

When a Charleston roof is done

Age is a clue, not a verdict. In its actual-cash-value example, the South Carolina Department of Insurance’s Post-Disaster Claims Guide treats the useful life of a roof as about 25 years, and a Lowcountry roof spends those years in heat and humidity, with salt air on top near the water. Condition decides it, and these signs point to replacement rather than another repair:

• bare, dark patches where the shingles have lost their protective granules
• a deck that an inspection finds soft or spongy, or stained, damp sheathing seen from the attic
• leaks that come back in new places after each repair
• wind or hail damage across several slopes that an inspection finds beyond repair

This has been a busy storm season. The National Weather Service logged 128 roof-relevant storm reports across the tri-county on 23 days between May 1 and September 29, 2026, more than in the same months of 2023, 2024 or 2025. If your roof took a hit, start with what to do first after storm or hail damage. If the trouble is one leak or one slope on a roof with years left, roof repair in Charleston is usually the better value.

What a full replacement involves on a Lowcountry home

Under the 2021 International Residential Code that South Carolina enforces, a roof replacement means removing the existing layers of roof covering down to the roof deck (Section R908.3). Ask how plantings, walkways and siding will be protected during the tear-off. With the deck exposed, expect the crew to walk it and replace sheathing that is soft or rotted; asphalt shingles have to be fastened to a solidly sheathed deck (R905.2.1).

Then the system goes back on. Underlayment covers the deck, and on slopes from 2:12 up to 4:12 the code calls for a double layer; below 2:12 asphalt shingles are not allowed (R905.2.2), so a low section gets a membrane instead. Where the design and the manufacturer call for it, a sealed or self-adhered secondary water barrier goes under the shingles, and drip edge goes on at the eaves and rakes where the shingle manufacturer requires it. Flashings at walls, valleys, chimneys and vents are rebuilt to the manufacturer’s installation instructions (R908.6), and existing flashings, edgings and vents are replaced where they are rusted, damaged or deteriorated (R908.5).

Fastening and the shingle’s wind rating follow the design wind speed. That speed comes from the Building Codes Council’s adopted wind-speed map for your county; the shingle has to meet the classification the code sets for it (R905.2.4.1), and your permit reviewer confirms what applies at your address. Attic ventilation is part of the same plan, sized to the code’s ratio.

Each of those steps moves the price, and our 2026 Charleston roof cost guide sets out what drives the number and what the market reports.

Shingles and metal that hold up on the coast

Three of GAF’s Timberline architectural shingle lines differ in ways that matter here. Timberline HDZ, Timberline UHDZ and Timberline AS II all carry ASTM D3161 Class F and ASTM D7158 Class H wind ratings. They part ways on hail: HDZ, GAF’s best-seller, is not rated Class 4 for impact, while UHDZ and the SBS-modified AS II are rated Class 4 under UL 2218, the highest class, which means a 2-inch steel ball dropped from 20 feet left no back-side fracture. In Lowcountry humidity, algae matters too: GAF’s StainGuard-labeled shingles carry a separate algae limited warranty, and only labeled products are covered.

Big Bear also installs standing-seam metal. It hides its fasteners, where exposed-fastener panels depend on washers that degrade under Southeast sun and need periodic re-fastening. Sections flatter than 2:12, such as porches and additions, take a continuous membrane like TPO, whose seams are heat-welded. You can see finished shingle and metal roofs in our project gallery.

Tear-off and overlays under South Carolina’s code

South Carolina enforces the 2021 International Residential Code, in effect since January 1, 2023, and its Building Codes Council has set January 1, 2027 as the effective date for the 2024 editions. The code allows a new covering over an existing one only in limited cases, such as a new covering installed under the manufacturer’s approved instructions (R908.3.1), and never where the existing roof is water-soaked or too deteriorated to serve as a base, is slate, clay, cement or asbestos-cement tile, or already has two or more layers of any covering (R908.3.1.1).

Permits go through the town or county office for your address. The page for our Charleston roofing contractor team lists the permit offices across the tri-county, city by city, with what each office’s own page says about re-roofing, and we handle the filing.

Insurance proceeds and financing

If a storm claim is paying for part of the roof, we inspect and document the damage to support your claim, and South Carolina law draws the line there: S.C. Code § 40-59-25(D) bars a contractor from representing a homeowner on a roof insurance claim, as our South Carolina roof insurance claim guide explains. Our roof financing guide covers how insurance proceeds and financing fit together, and Big Bear offers flexible financing options — ask your estimator.

GAF warranty tiers on a new roof

GAF’s contractor directory lists Big Bear Roofing in North Charleston as a GAF Master Elite contractor, and GAF reserves the Golden Pledge Limited Warranty, one of its strongest, for Master Elite contractors. Three enhanced tiers differ in who may offer them and in workmanship coverage:

• System Plus Limited Warranty: lifetime limited coverage for manufacturing defects across the GAF roof system, non-prorated for the first 50 years on eligible, qualifying installations, with no GAF coverage for installation errors. GAF Certified, Certified Plus and Master Elite contractors can offer it.
• Silver Pledge Limited Warranty: adds GAF coverage, for a shorter term, for misapplication of the shingles, accessories and covered flashings. Certified Plus and Master Elite contractors can offer it.
• Golden Pledge Limited Warranty: Master Elite contractors only. Its misapplication coverage is lifetime limited, non-prorated for the first 25 years, or 30 years on Timberline UHDZ, Timberline AS II and Designer shingles, and tear-off and disposal costs are included.

Every tier is subject to GAF’s current warranty document, and registering a Golden Pledge warranty is the contractor’s responsibility.

Frequently asked questions

What is the 25% rule for roofing, and does it apply in South Carolina?

Not in South Carolina. The 25 percent figure people read about comes from other states’ codes and some local conventions. South Carolina’s building-codes law, the Building Codes Council’s regulations and the state’s changes to the 2021 residential code set no such percentage. Here the test is layers and condition: a replacement strips the old coverings to the deck, and no new covering may go over two existing layers or a deteriorated roof.

Does South Carolina require drip edge on a new roof?

Where the shingle manufacturer requires it. South Carolina rewrote the model code’s drip-edge section, and its version of R905.2.8.5 requires drip edge at the eaves and rake edges of asphalt shingle roofs where required by the manufacturer. That makes the manufacturer’s installation instructions the document that settles it on your roof.

What is a six-nail pattern, and will my Charleston roof get one?

It means six nails per shingle instead of the four-nail minimum. The code sets the floor: the number of fasteners the manufacturer’s approved instructions require, and never fewer than four per strip shingle (R905.2.6). Six nails is the high-wind pattern where the wind design, the product approval and the manufacturer’s instructions call for it, and your permit reviewer confirms the design wind speed that applies at your address.

Is a Class 4 impact-rated shingle worth it in the Lowcountry?

It can be, so ask your insurance agent two questions first. A Class 4 roof may qualify for a premium discount, and the amount varies by carrier. Some carriers also attach a cosmetic-damage exclusion when they rate a Class 4 or metal roof. In GAF’s Timberline line, UHDZ and AS II are Class 4 and HDZ is not, so the shingle you pick decides whether the question applies at all.

How much attic ventilation does a new Charleston roof need?

South Carolina’s 2021 code sets net free ventilating area at 1 square foot per 150 square feet of vented attic (R806.2), or 1 per 300 when 40 to 50 percent of it sits high, no more than 3 feet below the ridge, with the rest in the bottom third. The warranty cares too: GAF’s sample Golden Pledge warranty does not cover damage resulting from inadequate ventilation.

What does a lifetime limited warranty on GAF shingles mean?

In GAF’s terms, a lifetime limited warranty lasts as long as the original individual owners of a single-family detached home, or a second owner after a proper transfer, own the property. It is not unconditional: coverage is non-prorated only for the period the warranty states and prorated after that, and it takes effect only once its eligibility requirements are met, it is registered and the roofing contractor has been paid in full.

Where does the old roof go after the tear-off in Charleston County?

Usually not to the county landfill. Charleston County’s page for the Bees Ferry Landfill says it does not accept construction and demolition waste from private or commercial haulers, so contractor tear-off goes to a private construction-and-demolition or recycling facility. Ask any roofer where the debris will go before the work starts.

Before you sign anything, get eyes on the roof. Big Bear’s inspections are free and no-obligation, drone-assisted where it helps, and they end with a plain answer on what your roof needs. Request a free inspection to start.