Research by DoINeedAPermit Research Team · Updated May 2026
The Short Answer
Yes. Any attached deck in Siloam Springs requires a building permit, regardless of size or height. The city requires structural review, ledger flashing detail, and footing inspection before construction begins.
Siloam Springs enforces Arkansas state building code (2012 International Building Code with amendments) and requires a permit for every attached deck, with no exemptions based on square footage or deck height alone. Unlike some neighboring cities in Benton County that exempt freestanding decks under 200 square feet, Siloam Springs' Building Department treats attachment to the house as the trigger — the moment a ledger bolts to your rim joist, a permit is required. This means a small 8x10 attached deck ($2,000–$3,000 material cost) still needs a plan submission and three inspections. The city's primary concern is ledger flashing compliance (IRC R507.9) and footing depth relative to the local 6- to 12-inch frost line, which varies across town depending on whether your lot sits in the rocky Ozark foothills or the softer Mississippi alluvium. A few lots near the Buffalo National River buffer zone may also trigger Army Corps of Engineers coordination, though that's rare. Siloam Springs' permit staff review deck plans in-house (no third-party engineer required for decks under 200 sq ft and 12 feet high) and typically turnaround plan review in 7–10 business days if you submit a clean detail sheet.

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

Siloam Springs attached deck permits — the key details

Siloam Springs requires a building permit for any deck attached to the house, per the city's adoption of the 2012 IBC with Arkansas amendments. The distinction between 'attached' and 'freestanding' is the critical pivot: if your deck ledger bolts to the house rim joist or band board, it needs a permit. If you build a 16x12 freestanding deck sitting on isolated footings 4 feet away from the house, Siloam Springs' code allows it without a permit as long as it stays under 30 inches above grade and 200 square feet — but the moment you add a connecting beam or ledger, you cross the line. The city's Building Department does not offer a counter-service fast-track for small decks; all attached decks follow the same review path: submit plans (pen-and-paper or PDF), wait 7–10 days for review, get conditional approval (usually with notes on ledger detail), and schedule three inspections (footing/framing, framing final, electrical if applicable). There is no administrative exemption even for decks under 100 square feet.

Ledger flashing is the single most common reason Siloam Springs' inspectors reject or fail deck plans. The city enforces IRC R507.9 strictly: your ledger must sit on a continuous flashing membrane that extends above the siding and wraps under the house's weather barrier, with Z-flashing or equivalent metal flashing protecting the band board. Many homeowners and contractors assume tar paper or caulk alone will work; it won't. The inspector will ask for a detail drawing showing the flashing sequence — top edge under shingles or trim, vertical leg between ledger and rim, bottom edge extending at least 2 inches below the band board with a drip-edge lip. Siloam Springs' Building Department has posted a one-page ledger-flashing checklist on the city website (or will email it on request); use it. Aluminum Z-flashing (~$0.30/foot) plus a $200–$300 rework if you install it wrong is cheaper than a failed footing inspection or a rotted rim joist in three years.

Footing depth and frost line are geography-dependent within Siloam Springs city limits. The northern and western neighborhoods (Ozark foothills) typically have rocky, draining soil and a frost line at 6 inches; the eastern flatlands (Mississippi alluvium) may reach 8–12 inches depending on seasonal water table. Siloam Springs Building Department's standard requirement is 8-inch footings minimum, but if your soil is known to freeze deeper, you must go deeper or the inspector will fail you. If you're unsure, a soil probe ($0–$50 for a hand auger, or $300–$500 for a professional soil report) is cheap insurance. Posts should be set on concrete footings below frost line, with the concrete pad at least 12 inches above grade (to keep posts dry and prevent wood rot). Pier-and-beam (post-on-pad) is standard; helical footings are not required unless soil is unstable or site is a known flood hazard. Most decks in Siloam Springs use pre-cast concrete footings (Home Depot piers, ~$15 each) or on-site pour; either works if the hole is deep enough.

Stairs and landing dimensions are regulated under IRC R311.7. If your deck is more than 30 inches above grade, you must have stairs. Each stair tread must be 10–11 inches deep (nose-to-nose), rise must be 7–8 inches (heel-to-heel), and the top landing of the stairs must be at least 36 inches wide — standard for a single-width staircase. A landing that's only 32 inches wide will fail inspection. Guardrails must be 36 inches high (measured from the deck surface to the top of the rail) and spaced so a 4-inch sphere cannot pass through any gap (balusters ~4 inches apart). Siloam Springs does not enforce a 42-inch rail height as some hurricane-prone cities do; 36 inches is code. String connections, lag bolts, and post-to-beam attachment must be detailed on your plan — standard DTT (deck tie-tie) or lateral load clips per IRC R507.9.2 are the norm. If stairs connect the deck, they are part of the permit and must be detailed as well.

Electrical and plumbing on decks trigger additional submittals and fees. If you're adding a 120V outlet or lighting to the deck, the electrician must pull a separate electrical permit (typically $75–$150 in Siloam Springs); if you're adding a gas line or water line, plumbing and/or mechanical permits apply. These are separate from the deck structural permit and are sometimes reviewed by different departments (Electrical Inspector, Plumbing Inspector). Plan ahead: if you want deck lighting or a hot-tub water line, request 'rough-in' inspection timing so electrical and plumbing happen before you seal the deck framing. A typical deck permit for a 12x16 attached deck with stairs (no electrical) runs $200–$350; add ~$75–$150 if you include lighting circuits. Siloam Springs does not charge a 'project valuation' fee for decks under 200 sq ft; they use a fixed-scope permit fee instead.

Three Siloam Springs deck (attached to house) scenarios

Scenario A
12x16 attached pressure-treated deck with stairs, 18 inches above grade, wood steps, no electrical — typical residential addition
You're adding a 12x16-foot deck off the back of your home in the Sycamore Creek neighborhood (eastern Siloam Springs, alluvium soil, 10-inch frost line). Deck height is 18 inches, so stairs are required. You plan pressure-treated 2x8 joists, pressure-treated ledger bolted to the house rim joist with Simpson strong-tie connectors, and three wood stair steps down to grade. Total material cost is approximately $3,500; contractor labor is $2,000–$3,000. You need a building permit. Submit a plan that includes (1) a site plan showing deck location, setbacks from property lines, and lot drainage, (2) a framing plan with joist spacing, post locations, and footing depths (8 inches minimum in this soil), (3) a ledger detail showing Z-flashing, ledger bolt spacing (16 inches on-center per IRC R507.9), and connection to the rim joist, and (4) a stair detail showing tread depth (10.5 inches), rise (7.5 inches), and 36-inch-wide landing. Siloam Springs' Building Department will review in 7–10 business days and return with 'Approval — conditional on corrected footing detail' or similar. You'll schedule three inspections: (1) footing/excavation (before concrete pour, 1–2 days), (2) framing (before decking is installed, 1–2 days), and (3) final (after deck is complete, including stair tread measurements). Total permit timeline is 3–4 weeks from submission to final approval. Permit fee is $250–$300 based on deck area. If you skip the permit and the city receives a complaint, you face a stop-work order, $400 fine, and a demand to remove the deck or retroactively permit and reinspect (adding $500–$1,000 in fees and delays).
Permit required | Ledger flashing detail mandatory | 8-inch footing depth (alluvium) | Simpson HUS210 or equiv. ledger bolts | Z-flashing ~$50 | Permit fee $250–$300 | Plan review 7–10 days | Three inspections required | Total project cost $5,500–$6,500
Scenario B
8x10 attached composite deck with no stairs, 24 inches above grade, deck lighting (120V) — North Ward residence near Ozark foothills
You're building a small raised deck on the north side of your home in the North Ward (rocky Ozark foothills, 6-inch frost line, good drainage). The deck is only 8x10 feet (80 sq ft) and 24 inches high — below the 30-inch stair threshold, but the 24-inch height is tall enough that you might add stairs later, so footings still need to be below frost. You want to add two recessed LED lights on the deck rim, so you'll need an electrician to run a circuit from the house. Composite decking (Trex or equivalent, ~$2,000) is more durable than pressure-treated in this damp Ozark climate where wood rot is common near tree shade. Your contractor will bolt a composite ledger equivalent to the house rim joist and set posts on 6-inch-deep concrete footings (below the local frost line). Permit submission includes the standard framing plan, ledger detail with composite-compatible flashing, footing detail, and — because you're adding electrical — a separate electrical rough-in plan showing light fixture location and circuit protection. Siloam Springs' Building Department will approve the structural permit in 7–10 days; the Electrical Inspector will add a separate electrical permit (~$100) and schedule a rough-in inspection before you close in the deck. Total permit fees are $250 (structural) + $100 (electrical) = $350. Inspections include footing, framing, electrical rough-in (before decking is installed), and final (after lights are wired). Total timeline is 3–4 weeks. Material cost is ~$2,800 (composite decking + ledger + posts + footing); permit and inspection timeline should not delay your schedule if you coordinate with both departments upfront. If you install the lights without a permit, Siloam Springs' electrical inspector can fine you $300–$500 and require removal and rewiring to code.
Permit required (attached + electrical) | Structural permit $250 | Electrical permit $100 | Footing depth 6 inches (Ozark foothills) | Composite-compatible ledger flashing required | Rough-in and final electrical inspections | Total permit cost $350 | Total project cost $3,500–$4,200
Scenario C
20x12 attached pressure-treated deck with no stairs, 32 inches above grade (near 30-inch threshold), detached hot tub plumbing — South Hills neighborhood flood-adjacent lot
You're adding a large 20x12-foot deck (240 sq ft) in South Hills, an area near Beaver Lake and subject to occasional flood advisories. The deck will be 32 inches above grade — just above the 30-inch stair threshold, so technically you may be able to use a ramp instead of stairs (if slope is ≤1:12 per IBC 1015), but the city will want to see the ramp detail. More importantly, your site is in a flood zone (Zone AE, per FEMA maps), and Siloam Springs' floodplain management office may require elevation certification or additional setback. You're also planning a hot tub on the deck, which means you'll need a plumbing permit for the water supply and drain line running from the house. This is a complex permit. Your submission must include (1) a structural deck plan with footing depths (8–10 inches depending on soil probe results, possibly deeper in saturated soil near the lake), (2) a ledger detail with flashing, (3) a ramp or stair plan (if stairs, full stair detail; if ramp, slope and handrail detail), (4) a floodplain elevation certificate if required by the city, (5) a plumbing plan showing hot tub water-supply and drain lines, connection to the house main, and septic or municipal drain tie-in. Siloam Springs' Building Department will forward the floodplain question to the Community Development / Floodplain Administrator (usually 5–10 day turnaround) and the plumbing plan to the Plumbing Inspector. Total permit fees: $250 (deck structural) + $100 (plumbing) + $0–$200 (floodplain elevation, if required) = $350–$550. Inspections will include footing, framing, plumbing rough-in, electrical (if hot tub is 240V), and final. Timeline can stretch to 4–6 weeks due to floodplain review, but this protects you from future flood-damage liability and insurance denial. If you skip the plumbing permit, your homeowner's insurance may deny a claim if the hot tub line ruptures or freezes, costing thousands in water damage. If you skip the floodplain review and the house is later flagged in a flood study, you could face a requirement to remove the deck or elevate it further.
Permit required (structural + plumbing + floodplain review) | Deck structural permit $250 | Plumbing permit $100 | Floodplain elevation fee $0–$200 (depends on study) | Footing depth 8–10 inches (soil-dependent, near water table) | Ledger flashing + ramp/stair detail required | 4–6 week timeline (floodplain hold) | Total permit cost $350–$550 | Total project cost $6,000–$10,000

Every project is different.

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

Siloam Springs frost depth and footing requirements — why local soil matters

Siloam Springs sits at the boundary of three soil provinces: the flat, soggy Mississippi alluvial plain to the east; the rocky, well-drained Ozark plateau to the north and west; and a transition zone in the middle. The city's frost line varies from 6 inches in the northern hills (where bedrock is close and drainage is excellent) to 8–12 inches in the eastern flatlands (where clay and silt hold moisture longer and frost penetrates deeper). Siloam Springs' Building Department uses an 8-inch minimum footing depth as the default, but your lot may differ. If you're building in a wet area or near a drainage swale, or if you have heavy clay soil, you should dig deeper or order a soil probe.

A soil probe costs $0 to $50 if you do it yourself (hand auger from a rental shop) or $300–$500 if you hire a soil engineer. For a deck, the hand-auger method is usually fine: dig a hole 12 inches deep on your lot, watch for the water table and soil color changes, and ask your neighbor or the Building Department 'where does frost typically reach here?' If you find a water table at 8 inches, footings need to be below that and below frost — potentially 12–14 inches. Siloam Springs' Inspector will ask to see the footing detail on your plan; if you show 8 inches and the soil is clearly wet, they will ask you to go deeper. A 4-inch mistake costs you an extra $200–$500 in concrete and a failed inspection; a soil probe upfront prevents that.

Post-installation, inspect your footings every 3–5 years (especially if you have a wet site). Frost heave can push isolated footings upward over time, and wood-rot can weaken posts at the soil line. Siloam Springs' winter climate is mild (rarely below 0°F), so frost heave is less violent than in Minnesota, but it still happens in wet years. Keep gutters clean and ensure deck-area drainage slopes away from posts to minimize water pooling.

Ledger flashing in Siloam Springs — the most failed detail and how to get it right

Siloam Springs' Building Department has seen ledger failures because contractors or DIYers install the ledger directly on the band board with only caulk or tar paper, and within 2–3 years, water seeps behind the ledger, rots the rim joist, and the deck pulls away from the house (or collapses). The 2012 IBC / IRC R507.9 requires a continuous flashing membrane. Siloam Springs' Inspector will ask for a detail drawing showing the flashing. The detail should show (1) the ledger board, (2) metal Z-flashing or equivalent (aluminum is standard, ~$0.30/foot), (3) the flashing top edge under the house siding or trim, (4) the flashing vertical leg between ledger and rim, and (5) the flashing bottom edge extending at least 2 inches below the band board with a drip-edge lip pointing downward. No tar paper alone. No caulk as the primary water barrier.

Order your Z-flashing by the linear foot: a 12-foot ledger needs 12 linear feet of flashing (~$4). Installation is straightforward: slip the top edge under the siding (or behind the house wrap if siding is vinyl or composite), nail the top edge every 16 inches, position the vertical leg tight against the rim joist, and nail the bottom edge to the band board every 16 inches. Use stainless-steel fasteners (not galvanized, which corrodes) so rust doesn't stain the siding. If your house has brick veneer, the flashing detail is trickier — you may need to remove a course of brick and tuck the flashing behind, or use a site-built metal channel. Ask your Siloam Springs Inspector or a detail-conscious contractor for advice before you start.

Ledger bolts must also be detailed. IRC R507.9 requires bolts (or approved fasteners) every 16 inches along the ledger, minimum 1/2-inch diameter. Simpson Strong-Tie HUS210 or HUS310 (two-piece connectors) are the modern standard and are what Siloam Springs' inspectors expect to see on deck plans. Older tap-bolt-only details are approved but less common. If your plan shows ledger bolts, the Inspector will spot-check 2–3 bolts during the framing inspection to confirm they're the right size and torqued correctly. Don't skip this detail or assume caulk is enough.

City of Siloam Springs Building Department
Siloam Springs City Hall, Siloam Springs, AR (exact address: contact city or search 'Siloam Springs Building Department')
Phone: (479) 524-6330 or (479) 524-3131 (City Hall main line — ask for Building Department) | https://www.siloamsprings.com (city website; check for online permit portal or submit in person)
Monday–Friday, 8:00 AM – 5:00 PM (verify locally; may vary)

Common questions

Is a freestanding deck exempt from permit in Siloam Springs?

Yes, if it's under 30 inches above grade AND under 200 square feet AND has no attachment to the house. The moment you bolt a ledger to the rim joist, it becomes 'attached' and requires a permit, regardless of size. Freestanding decks must still be set on footings below the 8-inch frost line (or deeper in wet soil), but you don't need city approval if you meet the size and height exemptions. If unsure whether your design qualifies, ask Siloam Springs' Building Department before you build.

How much does a deck permit cost in Siloam Springs?

A typical attached deck permit (no electrical) is $250–$350. If you add electrical (lighting, outlet), add $100–$150 for an electrical permit. If you add plumbing (hot tub, water line), add $100–$150. Siloam Springs does not charge by project valuation for decks; they use a fixed permit fee. A 12x16 deck with stairs costs the same permit fee as an 8x10 deck.

Do I need a professional engineer or architect for my deck plan?

No, not for a typical single-family residential deck under 200 sq ft and 12 feet high. Siloam Springs allows 'pen-and-paper' or CAD plans submitted by the homeowner or contractor, as long as the plan includes the required details (site plan, framing plan, ledger detail, footing detail, stair/ramp detail). If your deck is unusually large (over 200 sq ft), unusually high (over 12 feet), or in a flood zone, the city may require an engineer's stamp — ask before you submit.

Can I build my own deck in Siloam Springs, or do I need a licensed contractor?

Owner-builders are allowed in Siloam Springs for owner-occupied homes. You can pull the permit in your name and do the work yourself, or you can hire a contractor and have them pull the permit in their name. Either way, the permit is required, and all inspections must happen. If you're an owner-builder, you still need to understand the code requirements (ledger flashing, footing depth, guardrail height, etc.) or hire someone who does.

What if my deck site is in a flood zone? Does that change the permit?

Yes. If your lot is in FEMA flood Zone AE (near Beaver Lake or a creek), Siloam Springs' Floodplain Administrator must review and approve deck footings and elevation. You may need an elevation certificate ($300–$500) and may be required to set footings below the base flood elevation (BFE). This adds 1–2 weeks to the permitting timeline and possibly requires deeper footings or even deck relocation. Check your FEMA map online (search 'FEMA Flood Map Siloam Springs') before you design the deck.

How long does it take to get a deck permit approved in Siloam Springs?

Plan review typically takes 7–10 business days from submission. If your plan is incomplete or non-compliant (e.g., ledger flashing missing), the city will return it with comments, and you'll resubmit a corrected plan (add 3–5 more days). Once approved, scheduling inspections can add another 1–2 weeks depending on inspector availability. Total timeline: 3–4 weeks from submission to final approval. Flood-zone permits may take 4–6 weeks due to floodplain review.

Can I add a hot tub to my deck without a separate permit?

No. A hot tub requires a plumbing permit (water supply and drain line) and usually an electrical permit (240V circuit, GFCI protection). These are separate from the deck structural permit. Siloam Springs charges $100–$150 for a plumbing permit and $100–$150 for an electrical permit. You must coordinate timing: rough-in inspections for plumbing and electrical happen before you close in the deck framing.

What inspections are required for a deck permit in Siloam Springs?

Standard deck inspections are (1) footing/excavation (before concrete pour), (2) framing (after posts, ledger, and joists are installed but before decking), and (3) final (after all work is complete). If you have electrical, add an electrical rough-in inspection. If you have plumbing, add a plumbing rough-in inspection. Schedule inspections by calling the Building Department; most are available within 2–3 business days of request.

If my neighbor complains about my unpermitted deck, what happens?

Siloam Springs' Building Department will issue a stop-work order and fine you $300–$500. You'll be required to either remove the deck or retroactively permit and reinspect it. Retroactive permitting can cost $500–$1,500 in additional fees and may fail inspection if the deck was built non-code. It's faster and cheaper to get the permit before you build.

Will my homeowner's insurance cover damage if the deck wasn't permitted?

Unlikely. If the deck collapses or causes injury and your insurer discovers it was built without a permit, they may deny the claim entirely. If someone is injured on an unpermitted deck, you could be personally liable for medical costs and damages ($50,000+). Permits protect you — get one.

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 Siloam Springs Building Department before starting your project.