Research by DoINeedAPermit Research Team · Updated May 2026
The Short Answer
Full roof replacement, tear-offs, and material changes in Dunwoody require a building permit. Repairs under 25% of roof area may be exempt if no tear-off is involved. If a roof inspector finds three existing layers, IRC R907.4 forces a complete tear-off and triggers permit jurisdiction.
Dunwoody Building Department enforces Georgia's adoption of the 2022 International Building Code, which means IRC R907 reroofing rules apply—including the mandatory three-layer limit. What makes Dunwoody specific: the city operates a straightforward online permit portal and enforces pre-permit roof inspections for re-roofing to catch multi-layer violations before permit issuance. Many surrounding DeKalb County jurisdictions accept a contractor's affidavit; Dunwoody's policy is stricter—expect a city inspector to verify layer count on-site before you pull. The city's frost depth (12 inches) and warm-humid climate (Zone 3A) means ice-and-water-shield requirements differ slightly from northern states; you'll need underlayment extending 24 inches up from the eaves per IRC R905.1.1, but not the aggressive Minnesota-style hip-and-ridge strips. Material upgrades (shingles to metal, or shingles to clay tile) require structural review if the new material weighs more than 10 psf above your deck's design rating.

What happens if you skip the permit (and you needed one)

Dunwoody roof replacement permits — the key details

Dunwoody Building Department enforces the 2022 International Building Code (IBC 1511 and IRC R907) for all roof replacements. The city defines a roof replacement as any project involving tear-off of existing roofing, removal of one or more layers, or replacement of 25% or more of roof area. Per IRC R907.4, if field inspection reveals three existing layers of roofing on your home, complete tear-off to the deck is mandatory; no overlays permitted. This is the single largest surprise in Dunwoody reroofing permits—many homeowners assume they can overlay a third layer, but the code forbids it. The city's pre-permit inspection process (done by Dunwoody Building Department staff or a third-party inspector they approve) costs $75–$150 and must happen before you pull the main permit. This upfront inspection catch prevents costly permitting delays mid-project.

Permitting thresholds in Dunwoody are clear: full replacement, partial replacement exceeding 25% of roof area, any tear-off-and-replace, structural deck repair, and material changes all require permits. Exempt work includes repairs under 25% of roof area using like-for-like material (e.g., replacing 8 shingles on one slope with matching asphalt shingles), gutter and flashing-only repair without deck involvement, and re-nailing or re-fastening of existing roofing without removal. If you're unsure whether your scope crosses the 25% threshold, the Dunwoody Building Department's online permit portal includes a scope-calculator tool; staff also respond to pre-application questions via email within 24–48 hours. The permit fee in Dunwoody is typically $150–$400, calculated as a percentage of project valuation (often 0.5–1.5% of the re-roofing contract cost, with a $150 minimum). A $15,000 re-roof usually runs $200–$300 in permit fees.

Underlayment, fastening, and ice-and-water-shield specs are critical in Dunwoody's warm-humid climate (Zone 3A). Per IRC R905.1.1, synthetic underlayment or Type 1 asphalt-saturated felt is required; the city does not accept cardboard-backed tar paper without secondary bracing. Ice-and-water-shield must extend a minimum of 24 inches up from the eave (measured from the eave line inward, per IRC R905.2.8.1). For hip-and-ridge details, Dunwoody allows standard asphalt ridge caps in the warm zone (no specialized cold-climate requirements as would apply in Minnesota or Wisconsin). All fastening patterns must be specified in the permit application—typically 6 nails per shingle for standard 3-tab asphingles, or per manufacturer specs for architectural or premium shingles. If you're upgrading to metal roofing or clay tile, you must provide a structural engineer's letter confirming that your roof deck and framing can handle the additional dead load; metal is light (1.5–3 psf), but clay tile is heavy (9–15 psf). Dunwoody's inspectors will request this letter at permit issuance if material change is involved.

Georgia state law (Georgia Code § 43-41) allows homeowners to pull permits and perform roof work themselves, but Dunwoody's practice is that reroofing is almost always contractor-pulled. The reason: the city's pre-permit inspection and three-layer verification require a licensed roofer's affidavit stating the current layer count and plan for disposal. If you hire a contractor, they pull the permit, submit the pre-inspection, and coordinate the two inspections (deck-nailing and final). If you self-permit as owner-builder, you'll be responsible for requesting and passing the pre-inspection, then coordinating in-progress and final inspections yourself. Most owner-builders find it simpler to hire a licensed roofer for the labor and have them manage permitting. The city's Building Department office in downtown Dunwoody is open Mon–Fri 8 AM–5 PM; permits can be pulled online 24/7 via the city's permit portal.

Inspection sequence and timeline: Once your permit is issued, the city schedules an in-progress inspection (deck nailing) within 3–5 business days; your contractor must notify the department 24 hours in advance. The inspector verifies fastening pattern, deck condition, and underlayment installation. Final inspection occurs after shingles/metal is installed and ridge caps/flashing are complete; this typically happens within 2 weeks of in-progress inspection. Total timeline from permit issuance to final approval is 2–4 weeks. If any defect is noted (e.g., fastening misses, ice-and-water-shield gap), the inspector flags the issue and re-inspection is required (adds 1–2 weeks). Pro tip: Dunwoody's Building Department now offers expedited review (4-day turnaround instead of 7–10) for $50 additional fee if you pre-submit plans and photos 48 hours before permit application.

Three Dunwoody roof replacement scenarios

Scenario A
Standard like-for-like asphalt shingle replacement, 2,400 sq ft ranch home in Perimeter Center (no pre-existing layers beyond 2)
Your 1970s ranch has an original asphalt shingle roof plus one re-roof layer (2 layers total). You want to replace all shingles with 25-year architectural shingles, same slope and layout. Pre-permit inspection confirms 2 layers; no tear-off forced. You pull a standard roof replacement permit through Dunwoody's online portal, submitting the roofer's affidavit, product specs for the new shingles (e.g., GAF Timberline HD), and a fastening plan (6 nails per shingle, per manufacturer). Permit cost: $225 (based on ~$18,000 material + labor, roughly 1.25% of valuation). In-progress inspection occurs day 3 after permit issuance; final inspection within 10 days. Total timeline: 2–3 weeks. Because you're staying with asphalt-on-asphalt and no structural change, this is the smoothest track. The city does not require structural engineer letter. Contractor pulls permit, coordinates inspections; you receive final Certificate of Occupancy (or Approval) within 3 weeks of project start.
Permit required | Pre-inspection: $75–$150 | Permit fee: $225 | In-progress + final inspection included | 2-layer deck acceptable | Fastening spec required | 2–3 weeks total timeline
Scenario B
Asphalt shingles to metal standing-seam roof, 2,200 sq ft colonial home on Grant Avenue (Dunwoody historic district)
You're upgrading to metal roofing for durability and style. Pre-permit inspection reveals existing asphalt shingles (1 layer); no tear-off mandate. However, metal roofing weighs ~2 psf, lighter than asphalt, so structural capacity is not a concern. What IS unique in Dunwoody: Grant Avenue falls within the Dunwoody Historic District overlay, which imposes material and color restrictions on roofing. Metal roofing in a matte charcoal or bronze tone must be approved by the Dunwoody Design Review Board before the building permit is issued. Plan for 2–3 weeks of Design Review back-and-forth before building permit is submitted. Once Design Review approval is in hand, you submit a standard reroofing permit with metal specs (standing seam, fastening pattern per metal manufacturer, underlayment type), product literature, and color sample. Permit fee: $250 (slightly higher due to material-change complexity, though no structural letter is needed for light metal). Roofing contractor pulls permit, but they must coordinate Design Review submission first. Total timeline: 5–7 weeks (2–3 for design review, 2–3 for building permit, then 2 weeks for construction and inspections). Cost: Permit + Design Review: ~$400 (depends on review complexity).
Permit required | Historic District Design Review required (2–3 weeks) | Pre-inspection: $75–$150 | Permit fee: $250 | Fastening spec per metal manufacturer | No structural letter (metal is light) | 5–7 weeks total timeline | Material/color approval mandatory
Scenario C
Three-layer roof detected during inspection, tear-off to deck required, same-slope asphalt replacement, Sandy Springs border home with existing gutter issues
Your 1990s home has three layers of asphalt shingles (original + two overlays). Pre-permit inspection by Dunwoody Building Department inspector confirms three layers; IRC R907.4 tear-off mandate triggered. You cannot overlay; deck must be exposed. Permit now includes tear-off, deck inspection, new underlayment, and replacement shingles. Permit fee increases to $400 (tear-off complexity, deck exposure risk, and mandatory deck nailing inspection). Your roofing contractor submits permit application with tear-off plan, deck photos, and fastening spec. Dunwoody's in-progress inspection now has two phases: (1) post-tear-off deck inspection (inspector checks for rot, structural damage, and nailing pattern readiness), and (2) post-shingle installation. If the inspector finds deck rot or structural repair needs, the permit is flagged and you must obtain a structural engineer's opinion before final approval (adds $500–$1,200 in engineering costs, plus repair costs if rot is present—red clay and humidity in Zone 3A can create rot risk in older homes). Timeline stretches to 4–6 weeks due to deck contingencies. Gutter work during roof replacement is bundled into the same permit if it involves deck or fascia; if gutters are separate re-hang, they may not require a permit if no structural work is involved.
Permit required | Three-layer tear-off mandatory (IRC R907.4) | Pre-inspection: $75–$150 | Permit fee: $400 | Deck inspection in-progress required | Possible structural engineer letter if rot detected | Fastening spec required | 4–6 weeks timeline (contingent on deck condition)

Every project is different.

Get your exact answer →
Takes 60 seconds · Personalized to your address

Why Dunwoody's three-layer rule matters: IRC R907.4 and the pre-permit inspection

The three-layer rule in IRC R907.4 is a fire-safety and structural-load standard, not a preference. Each layer of shingles and underlayment adds dead weight; three layers can approach 10–15 psf on older, lighter-framed homes. Dunwoody Building Department enforces this strictly because the city sits in the Piedmont region with older housing stock (1960s–1990s ranches and colonials) that often has multiple overlays. A pre-permit roof inspection by the city or an approved third party catches violations before you've paid for a full permit and contractor labor.

The inspection process works like this: You contact the city to schedule a pre-permit roof inspection (cost: $75–$150, takes 1–2 weeks to schedule). An inspector visits, gets into your attic or climbs the roof with binoculars, and counts existing layers. If two or fewer, you proceed with a normal permit. If three or more, the inspector issues a notice requiring tear-off to deck. Some homeowners discover a fourth or fifth layer buried under modern shingles—these are treated the same way: tear-off mandatory. This upfront clarity prevents the nightmare scenario of a contractor halfway through an overlay when code compliance is discovered, forcing work stoppage and costly re-mobilization.

Tear-off work adds $3,000–$7,000 to a re-roof project (for a 2,500 sq ft roof), plus 1–2 weeks of timeline. Dunwoody's permit fee for a tear-off is typically $400 (vs. $200–$250 for overlay-eligible work). The silver lining: once the deck is exposed, the inspector can verify deck condition and identify any rot or structural repair needs immediately, avoiding post-installation surprises. If rot is found, you're obligated to repair it (per building code) and provide proof before final approval; costs vary from $500 (localized repair) to $5,000+ (widespread structural work).

Climate and material choices in Dunwoody's warm-humid zone (3A): underlayment, ice-and-water-shield, and long-term durability

Dunwoody sits in IECC Climate Zone 3A (warm-humid), which shapes underlayment and secondary water barrier requirements. The city's warm winters (frost depth only 12 inches) mean ice dams are rare, but heavy rain and humidity are common. IRC R905.1.1 requires synthetic or asphalt-saturated felt underlayment; Dunwoody's inspectors do not accept paper-backed tar paper or cardboard underlayment without additional synthetic bracing. The standard choice is synthetic (polypropylene or polyethylene) underlayment rated for UV exposure, which lasts 90+ days exposed during construction and handles the wet Piedmont climate well.

Ice-and-water-shield (self-adhering membrane) must extend 24 inches up from the eave line, per IRC R905.2.8.1. In Dunwoody, this is primarily a wind-driven rain and water backup protection requirement, not an ice-dam protection (though winter rain does occur). The 24-inch minimum is measured horizontally from the eave edge inward along the roof deck; at hip-and-ridge, standard asphalt caps are adequate (no specialty cold-climate hip strips are needed). For valleys and skylights, ice-and-water-shield extends the full valley run and 36 inches around penetrations.

Material durability in Dunwoody's humid climate: 25-year asphalt shingles often last 18–22 years due to algae growth and UV degradation in warm, wet conditions. Many homeowners in the area upgrade to 30-year architectural or impact-resistant shingles, or switch to metal. Metal roofing is increasingly popular in Dunwoody because it resists mildew and lasts 40–60 years. Tile and slate, if structural capacity allows, also perform well in warm climates. Cost premium for metal is typically $3,000–$6,000 above standard asphalt for a 2,500 sq ft roof, but 30-year life-cycle cost is competitive.

City of Dunwoody Building Department
41 Perimeter Center East, Dunwoody, GA 30346
Phone: (678) 382-6800 (main city line; ask for Building Department) | https://www.dunwoodyga.gov/permits (online permit portal)
Monday–Friday 8:00 AM–5:00 PM ET (closed city holidays)

Common questions

Do I need a permit if I'm just replacing a few damaged shingles?

No, if you're replacing fewer than 10 shingles (roughly 1–2 squares) in a localized area and not removing an entire layer, this is maintenance and exempt from permitting. However, if storm damage affects 25% or more of the roof area, or if you're replacing shingles across multiple slopes, you cross into repair/replacement threshold and need a permit. When in doubt, call Dunwoody Building Department for a 5-minute phone clarification.

What if I hire a roofing contractor—do they pull the permit or do I?

In Dunwoody, the roofing contractor typically pulls the permit on your behalf. They submit the application, request the pre-permit inspection, coordinate with the city's inspectors, and keep you informed. You sign off on the permit as the homeowner. If you're doing the work yourself (owner-builder), you pull the permit, but you'll still need a licensed roofer or you to handle the pre-permit layer-count inspection affidavit. Most owner-builders hire the contractor for labor and have them pull permits; it's simpler.

How long does the pre-permit roof inspection take, and what if it reveals three layers?

Scheduling takes 1–2 weeks; the inspection itself is 30 minutes to 1 hour. If three layers are found, the inspector issues a tear-off notice. You're required to pull a tear-off permit instead of an overlay permit. This adds 1–2 weeks of timeline and $3,000–$7,000 to your project cost. Some homeowners get this notice and decide to postpone the re-roof; it's your choice, but you cannot proceed with an overlay if the city has flagged the three-layer condition.

I'm switching from asphalt to metal roofing—do I need a structural engineer letter?

No. Metal roofing (standing seam, metal shingles, etc.) typically weighs 1.5–3 psf, which is lighter than asphalt (2–4 psf). Dunwoody does not require a structural engineer's letter for metal upgrades because dead load decreases. However, if you're switching to clay tile or slate (9–15 psf), you must provide a structural engineer's letter confirming your deck and framing can handle the additional weight. Structural letters cost $500–$800 and require a site visit.

What's the permit fee for a roof replacement in Dunwoody?

Permit fees range from $150–$400, calculated as a percentage of project valuation (typically 0.5–1.5% of re-roofing contract cost, with a $150 minimum). A $15,000 re-roof is usually $200–$300 in permit fees; a $20,000+ project with tear-off might run $400. The pre-permit inspection adds $75–$150. Total pre-permit + permit cost is typically $300–$500 upfront.

Can I overlay a second layer if my roof only has one existing layer?

Yes. If the pre-permit inspection confirms only one existing layer, IRC R907.4 permits a one-layer overlay (bringing you to two total). This is cheaper and faster than a tear-off. However, Dunwoody recommends tear-off for best practice because you avoid potential deck issues and ensure the longest-lasting roof. Many contractors suggest tear-off even if overlay is legal, because future homeowners may want another re-roof within 20–30 years, and a three-layer roof will force a tear-off then.

What if my home is in the Dunwoody Historic District—does that affect my roof permit?

Yes. Homes in the Dunwoody Historic District (like Grant Avenue or Chamblee-Dunwoody Road areas) must submit roofing material and color selections to the Dunwoody Design Review Board before the building permit is issued. Approved colors are typically matte charcoal, brown, black, or slate; bright or unconventional colors are often rejected. Design Review takes 2–3 weeks and may require revisions. Budget an extra 3–4 weeks and $0–$200 (design review is often free, but fees apply if you hire an architect or consultant).

What happens if the city inspector finds rot during the deck inspection?

If rot is discovered during the in-progress deck-nailing inspection, the inspector issues a notice requiring you to repair the affected area before final approval. Localized rot repairs cost $500–$2,000; widespread structural rot can run $5,000+. You must hire a contractor, complete repairs, and request a re-inspection (adds 1–2 weeks). Piedmont red clay and humidity mean older homes sometimes have hidden deck rot. The pre-permit tear-off inspection mitigates this risk by exposing the deck.

Do I need a permit for new gutters or flashing work during a roof replacement?

If gutters or flashing work involves the roof deck, roof structure, or fascia replacement, it's bundled into the roofing permit and covered by the same fee. If you're just re-hanging gutters without deck or fascia work, Dunwoody does not require a separate permit. Talk to your contractor about whether gutter work qualifies as part of the roofing scope or separate maintenance.

How long does the entire permit and inspection process take from start to finish?

Timeline: 1–2 weeks to schedule pre-permit inspection, then 1 week for permit issuance (or 4 days if expedited for $50 extra), then 2–3 weeks for construction and inspections. Total: 4–6 weeks from first call to Dunwoody Building Department to final Certificate of Approval. Tear-off projects or deck issues can stretch this to 7–8 weeks. Start early if you want the roof done before fall or winter weather.

Disclaimer: This guide is based on research conducted in May 2026 using publicly available sources. Always verify current roof replacement permit requirements with the City of Dunwoody Building Department before starting your project.