Research by DoINeedAPermit Research Team · Updated May 2026
The Short Answer
Yes. Any attached deck in Dunwoody requires a building permit, regardless of size or height. The city enforces structural review, frost-depth footings (12 inches minimum), and ledger flashing compliance before you pour concrete or drive the first fastener.
Dunwoody's building permit requirement is stricter than many Georgia suburbs in one key way: the city actively inspects ledger-board flashing details on all attached decks, not just those over 200 square feet. This is because attached decks are the #1 water-intrusion liability in the Southeast's warm-humid climate (3A zone). Dunwoody also enforces the 12-inch Piedmont frost depth rigorously — inspectors will reject footings shallower than 12 inches, even if you've seen decks at 8 inches elsewhere in Georgia. The city uses an online permit portal and processes plan reviews in 7-10 days for most single-family residential decks; in-person submission is optional but speeds re-submission on minor corrections. Dunwoody's permit fee runs $200–$450 depending on deck valuation (typically 1.5% of project cost). Owner-builders may pull their own permits under Georgia Code § 43-41, but you'll still need a professional engineer's stamp on the plans if the deck is over 12 feet wide or over 4 feet above grade.

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

Dunwoody attached deck permits — the key details

Dunwoody requires a permit for any deck attached to a house, regardless of size. The city applies IRC R507 (decks) and IBC 1015 (guardrails) as its baseline, then enforces additional local amendments specific to the Southeast's moisture climate. The most critical local rule: ledger flashing must be a continuous barrier — metal flashing embedded under the house rim board and extending down over the band board. Dunwoody inspectors will reject any ledger-flashing detail that doesn't show this overlap and overlap direction in the plan. This rule exists because attached decks are the #1 source of water intrusion in Georgia homes; once water gets behind the ledger board, it rots the rim joist and band board in 3-5 years, requiring $15,000–$50,000 in foundation repair. The city will require a footing inspection before you backfill any footings — this is non-negotiable. Do not pour concrete footings without a city inspector sign-off on footing depth and soil bearing. Frost depth in Dunwoody is 12 inches (Piedmont soil classification); all footings must extend below 12 inches. If you hit granite or Cecil clay bedrock shallower than 12 inches, you must document this on a photo and submit a geology report or use approved frost-proof pier footings (Simpson EPB or equivalent), which cost $40–$80 per footing and eliminate the frost-depth risk entirely.

Plan submission in Dunwoody goes through the city's online permit portal (accessible via the Dunwoody Building Department website). You'll upload a two-page architectural plan (not a sketch) showing: a site plan with deck location, property lines, and setbacks; a framing plan showing joist size, spacing, ledger details, and post sizes; a footing detail showing depth and diameter; and a guardrail detail if the deck is over 30 inches above grade. The plan must be signed by a Georgia-licensed architect or engineer if the deck is over 200 square feet or over 4 feet above grade. For owner-builders (allowed under Georgia Code § 43-41), Dunwoody will accept owner-builder plans for decks under 12 feet wide and under 30 inches high without an engineer stamp, but you'll still need to show all structural details clearly. Plan review takes 7-10 business days; if the reviewer finds issues (wrong frost depth, missing flashing detail, guardrail height off), you'll get a marked-up plan and a 10-day cure period. Most decks require 1-2 rounds of corrections before approval. Once approved, you have a standard 6-month window to begin work and a 24-month window to complete it before the permit expires.

Inspections in Dunwoody follow the standard Georgia sequence: footing pre-pour, framing, and final. Footing inspection is critical — the city will visually confirm that all footings are dug to at least 12 inches depth and that the soil is undisturbed or properly compacted. The inspector will also verify that any ledger flashing has been installed before you backfill (this is your chance to show compliance). Framing inspection occurs once the deck frame is complete but before decking boards are installed; the inspector checks joist spacing, joist-to-beam connections, beam-to-post connections (must be bolted with ½-inch bolts, not toe-nailed), and guardrail framing if applicable. Final inspection checks decking fastening, guardrail height (minimum 36 inches, measured from the deck surface to the top of the rail), guardrail spacing (no more than 4 inches between vertical balusters — a 4-inch sphere must not pass through), and any stairs or ramps. Stairs must have a minimum 36-inch width, minimum 7-inch rise, maximum 10-inch tread, and a handrail on at least one side if more than three risers. Dunwoody inspectors are typically available within 24-48 hours of a request; you can request inspections through the online portal or by phone. Plan for 2-3 weeks total from plan approval to final inspection.

Dunwoody's permit fee is calculated as 1.5-2% of the estimated project valuation. A typical 16x12 attached deck with railing runs $8,000–$15,000; the permit fee will be $120–$300 before any local assessment fees (most cities add a 10% local tax). If you're pulling a combined permit for deck plus electrical work (outdoor lights, receptacles), expect an additional $100–$150 for electrical review. Plan review fees are bundled into the permit fee, not charged separately. Expedited review (5-day turnaround instead of 10) is available but rare for residential decks; ask the permit intake staff. If you need to revise plans after approval (e.g., you want to move the deck 5 feet west), you'll pay a $75–$150 plan-revision fee per resubmission.

Dunwoody also requires compliance with the city's zoning code, not just building code. Decks must comply with setback requirements (typically 5 feet from side lot lines, 10 feet from rear in residential zones, but verify your specific zoning via the city parcel map). If your deck encroaches on a setback, you'll need a variance from the Dunwoody Board of Zoning Appeals before the building department will issue a permit. Variances take 6-8 weeks and cost $300–$600 in application and legal fees; many homeowners avoid this by redesigning their deck to fit within setbacks. Dunwoody also has a historic-district overlay in parts of the city (primarily the downtown and Perimeter Center areas); if your property is in a historic district, your deck design must be reviewed by the Dunwoody Historic Preservation Commission before you submit a building permit. This adds 2-3 weeks to the timeline and roughly $200 in commission fees. Check your property deed or the city zoning map online to confirm whether you're in a historic district.

Three Dunwoody deck (attached to house) scenarios

Scenario A
12x16 treated-lumber deck, 3 feet above grade, rear yard, outside historic district and setback zone — single-family home near Chamblee
You're building a straightforward rear deck 3 feet above ground. The deck is 192 square feet (under 200 sq ft but still requires a permit because it's attached). Your plan shows 2x10 joists 16 inches on center, bolted to a 2x12 rim beam, with 4x4 treated-pine posts on concrete footings. The Dunwoody Building Department will require a footing detail showing 12 inches minimum depth (Piedmont frost line). Because the deck is 3 feet high, you'll need a 36-inch guardrail; the city will want to see that guardrail spacing is ≤4 inches (balusters, not pickets). The ledger board attaches to your house rim with ½-inch bolts 16 inches on center; flashing must be metal, embedded under the house rim, and extending down over the band board (this is the critical detail Dunwoody inspectors check first). No engineer stamp is required for owner-builders under 12 feet wide and under 4 feet high, so you can draw the plans yourself or use a simple online deck plan. You submit via the online portal: two pages showing site plan, framing, footing detail, and guardrail. Plan review takes 7-10 days. Footing inspection: you dig footings 12 inches deep, call the city, inspector confirms, you backfill and pour concrete (no pier footings needed). Framing inspection: deck frame is complete, inspector checks joist bolting and guardrail framing. Final inspection: all decking installed, guardrail finished, stairs (if any) compliant. Total permit fee: $150–$250 (depending on valuation). No variance needed if you're outside all setback zones (confirm with a property survey or the city zoning map). Timeline: 3-4 weeks from permit issuance to final sign-off. Material cost: $3,500–$6,000 (treated lumber, concrete, hardware). Labor (if you DIY): minimal. Labor (contractor): $2,000–$4,000.
Permit required (≥12 sq ft + attached) | Footing inspection mandatory | Ledger flashing detail required | Metal flashing over band board (critical) | ½-inch bolts 16 OC | 36-inch guardrail minimum | Dunwoody frost depth 12 inches | Permit fee $150–$250 | No engineer stamp (owner-builder, <12 ft wide, <4 ft high) | Total deck cost $5,500–$10,000
Scenario B
20x20 composite deck, 5 feet above grade, side yard, inside historic-district boundary — Arts and Crafts home in Dunwoody Village
You're building a larger composite deck (400 square feet, well over the 200 sq ft threshold). The deck is 5 feet above grade, which triggers structural review and means you'll need a professional engineer's stamp on the plans. Because your property is inside the Dunwoody Historic Preservation Commission district (check your deed; the Dunwoody Village area is predominantly historic), you'll also need Commission approval before the building department will issue a permit. Here's the workflow: (1) Submit a design (or have an architect sketch one) to the Historic Preservation Commission. They'll review the deck's visual appearance — color, railing style, material consistency with the home's era. This takes 2-3 weeks. If approved, you get a staff letter saying the deck is compatible. (2) Have a structural engineer draw a full framing plan showing composite joist specifications (composite joists have different load ratings than pressure-treated lumber and must be sized accordingly), ledger detail with metal flashing, footing detail showing 12-inch depth and soil bearing, and a guardrail plan showing 36-inch height and 4-inch balusters. Engineer stamps the plans. (3) Submit to Dunwoody Building Department via the online portal. Plan review takes 10-14 days because the engineer review takes longer. (4) Once approved, footing inspection (same as Scenario A, 12 inches minimum), framing inspection (inspector checks composite joist spacing and ledger bolting), and final inspection (guardrail, decking, stairs). The ledger flashing detail is even more critical here because composite materials are more moisture-sensitive than treated wood; Dunwoody will inspect it closely. Total permit fee: $280–$450 (composite deck flagged as higher-valuation, ~$15,000–$25,000 project). Historic-district design review: no fee, but adds 2-3 weeks. Setback compliance: confirm your deck fits within 5-foot side-yard setback (if not, you'll need a variance, which adds 6-8 weeks). Timeline: 5-7 weeks total (historic review + plan review + inspections). Material cost: $8,000–$15,000 (composite decking more expensive than treated lumber). Labor: $3,000–$6,000 (composite installation requires specialty fasteners and typically mandates contractor work).
Permit required (>200 sq ft) | Engineer stamp required (5 ft high) | Historic Preservation Commission approval required (2-3 weeks pre-permit) | Composite joist load ratings critical | Ledger flashing detail (metal, overlapped) | ½-inch ledger bolts 12-16 OC | 36-inch guardrail | 4-inch baluster maximum spacing | Footing depth 12 inches | Permit fee $280–$450 | Plan review 10-14 days | Total project $11,000–$21,000
Scenario C
10x10 ground-level pressure-treated deck, 18 inches above grade, no guardrail, no electrical, rear corner lot in Chamblee-adjacent area with potential setback conflict
You want to build a small 100 sq ft deck in the rear corner of your property, about 18 inches above grade (too high to be freestanding exempt but small enough to avoid the 200 sq ft threshold). The verdict depends on your lot configuration and setback requirements. First, check your deed and the Dunwoody zoning map to confirm your lot dimensions and setback rules. If your property is in a typical single-family residential zone, rear setback is usually 10 feet from the property line; side setback is 5 feet. A 10x10 deck is small enough that you might fit it, but you need to measure carefully. If the deck's rear edge and side edge are both within the required setbacks (10 feet from rear, 5 feet from side), you proceed with a standard permit application. If you violate either setback (e.g., the deck is only 8 feet from the rear property line), you'll need a variance from the Board of Zoning Appeals before Dunwoody will issue a permit. Variance route: file a variance application ($300–$600), attend a hearing (2-3 weeks timeline), argue hardship or practical difficulty, get approval or denial. Many corner-lot owners find they need a variance because the corner geometry leaves little room. Assuming no setback issue: the deck at 18 inches above grade technically requires a guardrail under IBC 1015 if the deck is more than 30 inches above grade. At 18 inches, guardrail is not required by code, but if anyone trips stepping off the edge, you have liability exposure — most builders recommend a small rail anyway. Plan submission is minimal: two-page detail showing joist size (2x8 or 2x10), 4x4 posts, 12-inch footings, and ledger flashing. Owner-builder plans acceptable (no engineer stamp needed for <12 ft wide, <4 ft high). Footing inspection at 12 inches, framing inspection when complete, final inspection. Permit fee: $120–$200. If a variance is needed, add 6-8 weeks and $300–$600 in legal/application fees to the timeline. Material cost: $2,000–$3,500. Labor: $800–$1,500 (contractor) or DIY savings if handy. Total timeline without variance: 3-4 weeks. Total timeline with variance: 8-10 weeks.
Permit required (attached deck) | Setback verification CRITICAL (10 ft rear, 5 ft side minimum) | May require variance if encroaching ($300–$600, adds 6-8 weeks) | Frost depth 12 inches | Footing inspection required | Ledger flashing detail required | 18-inch height (guardrail optional but recommended) | No guardrail required by code at <30 inches | Owner-builder eligible (no engineer stamp) | Permit fee $120–$200 | No variance: 3-4 weeks | With variance: 8-10 weeks | Total cost $2,800–$5,200

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Dunwoody's 12-inch frost depth and why it matters for your deck footings

Dunwoody sits in the Piedmont physiographic region of Georgia, characterized by Cecil soil (a red clay with moderate bearing capacity) and granite bedrock. The frost-depth requirement is 12 inches minimum — this means all deck footings must extend at least 12 inches below the finished grade before concrete is poured. This rule is non-negotiable in Dunwoody; inspectors will fail any footing less than 12 inches deep, even if you claim you've seen it done elsewhere. The 12-inch depth is based on ASHRAE climate data for the Atlanta metropolitan area; it represents the deepest penetration of sustained freezing temperatures at ground level. When soil freezes, it expands upward — a phenomenon called frost heave. A footing that sits above the frost line will move upward 1-3 inches during winter, then settle back down in spring, creating a rocking motion that eventually splits the post and destabilizes the deck.

If you dig a footing and hit granite bedrock at, say, 10 inches depth, you cannot simply pour concrete at 10 inches and call it good. Dunwoody will reject that. Your options are: (1) use an approved frost-proof pier system such as a Simpson EPB (elevated post base) that elevates the post above grade and allows frost heave to occur beneath, or (2) hire a soils engineer to document the granite and submit a geological report showing that bearing capacity is adequate despite the shallow depth — this is expensive ($400–$600) and often rejected anyway. Most builders choose option 1: frost-proof piers cost $40–$80 per footing and eliminate the frost-depth argument entirely by design. If you use frost-proof piers, submit a photo of your pier installation in the framing-inspection request; the city inspector will verify that the pier is rated for your post load and that the post is properly bolted to the pier.

This is also why composite or moisture-sensitive post materials (such as pressure-treated with copper-based preservatives) are critical: if your footing sits in standing water or seasonal saturation, the post will rot from the base upward. Dunwoody's warm-humid climate means moisture is always present in soil. Use a footing tube (cardboard or plastic sonotube) to prevent soil contact with concrete and ensure good drainage around the footing. Some builders add a 2-4 inch gravel pad beneath the footing to promote drainage. The footing inspection is your best friend here — an inspector will visually confirm that the footing is the right depth and that the soil is well-compacted and free of standing water.

Ledger-board flashing: Dunwoody's most-inspected detail and why water intrusion is a $50,000 problem

Dunwoody's building inspectors focus more heavily on ledger flashing than almost any other detail because attached decks are the #1 source of water intrusion and foundation rot in the Southeast. Once water gets behind the ledger board, it travels down inside the rim joist and band board, where it soaks into the wood framing for months or years before you notice. By the time you see rot, the rim joist and entire band board are compromised, and repair costs $15,000–$50,000 (you're removing the deck, cutting out rotten wood, installing new structural framing, and rebuilding the rim board). Prevention is vastly cheaper than repair. The code rule is simple: ledger flashing must be a continuous metal barrier embedded under the house rim board (the band board that sits on top of the foundation wall) and extending downward over the band board exterior. The overlap is critical — water must run down and off the metal, not behind it.

In practice, here's what Dunwoody inspectors look for in the framing inspection: (1) Metal flashing (aluminum or steel, not vinyl or tar paper) is installed in the gap between the house rim board and the deck ledger board, running the full length of the ledger. (2) The top of the flashing is embedded under the rim board (not just laid on top). (3) The bottom of the flashing extends at least 2 inches down the exterior of the band board. (4) The flashing is sealed with silicone caulk where it meets the ledger and house exterior — no gaps. (5) The ledger is bolted to the rim board with ½-inch galvanized bolts spaced 12-16 inches on center, not toe-nailed or fastened with nails alone. Nails will eventually back out as the wood settles; bolts hold. Most inspection failures on ledger details are caused by missing flashing or flashing that doesn't overlap properly. During plan review, Dunwoody will ask you to submit a detail drawing showing the flashing overlap and ledger bolting in a cross-section view; this detail must be 1/4-inch or 1/2-inch scale so the inspector can verify dimensions.

A common mistake: homeowners or inexperienced builders use a ledger board that's too thin (2x6 instead of 2x10) or install the flashing on top of the ledger instead of under the rim. Another common error: using standard roofing flashing (which is designed for a single-plane overlap) instead of ledger-specific flashing (which has a bent lip designed to direct water down and off). Dunwoody will reject both. Buy ledger flashing specifically — brands like Sill-Pan or equivalent are available at any lumber supply for $15–$30 per 10-foot section. During the framing inspection, the inspector will press on the flashing with a screwdriver or penknife to verify it's metal, not vinyl or rubber. They'll also pull gently on the ledger board to check that bolts are tight and the connection is rigid. If the ledger moves or flexes, the inspection fails and you'll be required to add bolts. Plan on 3-4 hours of labor to install flashing correctly; most contractors include this in their deck labor estimate ($200–$400).

City of Dunwoody Building Department
41 Perimeter Center East, Dunwoody, GA 30346
Phone: (678) 382-6800 | https://www.dunwoodyga.gov/building-development
Monday–Friday, 8:00 AM – 5:00 PM (closed holidays)

Common questions

Can I build a freestanding deck in Dunwoody without a permit?

Only if it meets all three conditions: freestanding (not attached to the house), under 30 inches above grade, and under 200 square feet. Even then, Dunwoody recommends a permit to avoid disputes at resale. Most attached decks require a permit because they're attached. If you're planning a freestanding deck under the exemption, get written confirmation from Dunwoody Building Department before you start work; email a photo and dimensions to the permit intake office.

Do I need a professional engineer for my deck plans?

Only if your deck is over 12 feet wide OR over 4 feet above grade. If both dimensions are smaller, owner-builders can draw plans themselves under Georgia Code § 43-41, and Dunwoody will accept them if they show all structural details clearly (joist size, spacing, bolt locations, footing depth, guardrail height). For larger decks, hire a Georgia-licensed engineer or architect; expect $400–$800 for plan preparation and stamp.

How deep do footings need to be in Dunwoody?

12 inches minimum below finished grade. Dunwoody enforces this strictly because the Piedmont frost line is 12 inches. If you hit bedrock shallower than 12 inches, you must use a frost-proof pier system (Simpson EPB or equivalent) or submit a geotechnical report; the latter is expensive and often rejected. Frost-proof piers cost $40–$80 each and are the easiest solution.

What's the most common permit rejection for decks in Dunwoody?

Missing or improper ledger flashing. Dunwoody inspectors will reject any ledger detail that doesn't show metal flashing embedded under the house rim board and extending down over the band board. Plan for 1-2 correction cycles before approval; if you see 'revise flashing detail' on your plan review comments, you're not alone. Use ledger-specific metal flashing (not roofing flashing) and ensure it overlaps at least 2 inches down the exterior.

Do I need a variance if my deck encroaches on a setback?

Yes. Dunwoody rear setback is typically 10 feet, side setback 5 feet (verify your zoning). If your deck violates either, you'll need a variance from the Board of Zoning Appeals before the building department will issue a permit. Variance applications cost $300–$600 and take 6-8 weeks. Many corner-lot owners discover they need a variance; plan accordingly or redesign your deck to fit within setbacks.

Is my property in the historic district, and does that affect my deck permit?

Check your deed or the Dunwoody zoning map online (dunwoodyga.gov). If you're in the historic-district overlay (primarily Dunwoody Village and downtown Perimeter areas), your deck design must be reviewed by the Historic Preservation Commission before you submit a building permit. This adds 2-3 weeks and involves a design review (no formal fee, but you must attend a public hearing). The Commission typically approves decks if they're consistent with the home's architectural era and painted or stained to match; bright colors or modern aluminum railings may be rejected.

What's the cost and timeline for a typical deck permit in Dunwoody?

Permit fee: $150–$450 depending on deck size and valuation (typically 1.5-2% of project cost). Plan review: 7-10 business days (longer if an engineer is involved). Inspections: footing pre-pour, framing, and final — total 2-3 weeks. Total timeline from submission to final sign-off: 3-4 weeks (no setback issues or historic review). If you need a variance or historic review, add 6-8 weeks. Material cost for a typical 16x12 treated-lumber deck: $5,000–$10,000. Contractor labor: $2,000–$4,000.

Can I use a ledger board thinner than 2x10?

Not recommended, and Dunwoody inspectors will scrutinize anything thinner. Use a 2x10 (or larger if span requires) ledger bolted to the house rim board with ½-inch bolts 12-16 inches on center. A thin ledger (2x6) won't develop enough bearing area to distribute deck load; it also provides less wood depth for flashing to embed under the rim. Thicker is better; err on the side of overbuilding the ledger connection.

Do I need a handrail or stair railing on my deck stairs?

Yes, if your stairs have more than three risers. Dunwoody requires a handrail on at least one side (two sides if stairs are wider than 44 inches). The handrail must be 34-38 inches above the stair nosing, with a continuous graspable profile (1.25-2 inches diameter). Balusters or spindles between the handrail and deck surface must be spaced no more than 4 inches apart (a 4-inch sphere must not pass through). Stairs must also have a landing at the bottom if the deck is more than one story high; landing dimensions are 36 inches minimum width, 36 inches minimum depth.

What happens during the footing inspection?

The inspector visits your site before you pour concrete footings. They visually verify that: (1) all footing holes are dug to at least 12 inches depth, (2) soil is compacted and free of standing water, (3) the footing tube (sonotube) is in place if using one, and (4) the ledger flashing has been installed on the house rim (the inspector will check that it's metal and properly overlapped). If everything is correct, the inspector signs off and you pour concrete. If anything is missing or non-compliant, the inspection fails and you'll be asked to re-excavate or install flashing before re-requesting inspection. Turnaround for footing inspection requests is typically 24-48 hours after you call.

Nearby cities & related guides

Deck (Attached to House) Permits in Augusta-Richmond County consolidated government, GA Deck (Attached to House) Permits in Macon-Bibb County, GA Deck (Attached to House) Permits in Athens-Clarke County unified government, GA
Disclaimer: This guide is based on research conducted in May 2026 using publicly available sources. Always verify current deck (attached to house) permit requirements with the City of Dunwoody Building Department before starting your project.

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