Alabama Building Codes, Permits and Contractor Rules
Here’s every rule from our 50-state guides for Alabama on one page: the residential building code, frost depth, retaining wall permits, the 811 dig law, drainage law, contractor licensing, deposit limits, mechanics lien deadlines, workers’ comp, planting zones and frost dates. Each section links the official source and the full 50-state comparison.
Alabama at a glance
- Building code: 2015 IRC (some areas only)
- Frost depth: Set by your local building department
- 811 notice: At least 2 but not more than 10 working days before excavation (not counting day of notice)
- Contractors: State license required
- Deposits: No statewide cap
- Liens: 6 mo. prime / 4 mo. sub, last furnishing
- Workers’ comp: 5+ (new home building: 1+)
- Drainage rule: Civil law (natural flow)
- Planting zones: 7b to 9b
| Topic | Alabama | Compare |
|---|---|---|
| Residential building code | 2015 IRC (some areas only) | All states |
| Frost line depth | Set by your local building department | All states |
| Retaining wall permit | Exempt if not over 4 ft measured from bottom of footing to top of wall, unless supporting a surcharge or impounding Class I, II or IIIA liquids (2015 IRC… | All states |
| 811 notice before digging | At least 2 but not more than 10 working days before excavation (not counting day of notice) | All states |
| Contractor license | State license required | All states |
| Deposit limit | No statewide cap | All states |
| Right to cancel | 3 business days, credit sales at home | All states |
| Lien filing deadline | 6 mo. prime / 4 mo. sub, last furnishing | All states |
| Workers’ comp required | 5+ (new home building: 1+) | All states |
| Drainage between neighbors | Civil law (natural flow) | All states |
| Planting zones (2023 USDA) | 7b to 9b | All states |
| Frost dates (NOAA) | Last frost early Mar (Mobile) to late Mar (Huntsville); first frost early Nov (Huntsville) to late Nov (Mobile) | All states |
Alabama residential building code
- Code
- 2015 International Residential Code with Alabama amendments (Alabama Residential Building Code)
- How it applies
- Statewide for some areas only
- In effect since
- October 1, 2016
- Code agency
- Alabama Energy and Residential Codes Board (Alabama Department of Economic and Community Affairs, ADECA)
- Who enforces it
- Applies to jurisdictions that had no residential code before March 2010; jurisdictions that already had a residential code may keep enforcing it. Permits and inspections are handled by local building departments.
- Good to know
- Alabama's state residential code is still based on the 2015 IRC, and cities that had their own code before 2010 may use a different edition. Check with your city or county building department before you build.
Compare building codes in all 50 states
Frost line depth in Alabama
- Who sets it
- Local building department
- Good to know
- Call your local building department for the frost depth that applies where you live.
Frost line depth in every state
Retaining wall permits in Alabama
- Permit exemption
- Exempt if not over 4 ft measured from bottom of footing to top of wall, unless supporting a surcharge or impounding Class I, II or IIIA liquids (2015 IRC R105.2 as adopted; Alabama's amendments change only IRC Chapters 3, 11, 24 and 34).
- Who decides
- Your city or county decides. If it had its own residential code before March 2010, that code governs; otherwise the state's 2015 IRC applies where it is enforced locally.
- Good to know
- Wall height is measured from the bottom of the footing to the top of the wall. If your city or county had its own residential code before March 2010, that code may still apply.
Retaining wall permit rules in every state
811 dig law in Alabama
- One-call center
- Alabama 811
- Notice before digging
- At least 2 but not more than 10 working days before excavation (not counting day of notice)
- Ticket good for
- 20 working days from proposed start date (demolition: 30 working days); renew at least 2 working days before expiration
- Hand-dig zone
- Width of the facility plus 18 in. on either side of the outside edge (horizontal plane)
- Homeowners
- Law's 'excavation' definition covers mechanized equipment or explosives. Notice not required for persons excavating on their own property/easement when no other operator has underground facilities there, or for agricultural plowing under 12 in. Alabama 811 says anyone who plans to dig should contact 811. From Jan 1, 2027 (SB205), a property owner using unmechanized (hand) tools on their own property is expressly excluded from 'excavation'.
- The law
- Code of Ala. § 37-15-1 et seq. (Alabama Underground Damage Prevention Law)
- Good to know
- A rewrite of the law (SB205) takes effect Jan 1, 2027. It keeps the 2 to 10 working day notice, 20-working-day ticket and 18 in. zone, and adds rules for complex or large projects.
Drainage law and stormwater permits in Alabama
- Rule
- Civil law (natural flow)
- The rule
- Modified civil law: the upper owner may alter or concentrate the flow to improve the property but may not unduly burden the lower owner by causing substantial damage.
- Leading case
- Street v. Tackett. 494 So. 2d 13 (Ala. 1986)
- What it means for your yard
- You can regrade, add downspouts or build a patio to improve your property, but if the change sends enough water onto a neighbor to cause substantial damage, you can be liable.
- Construction stormwater permit
- Alabama Department of Environmental Management (ADEM): 1 acre or more of land disturbance (or less if part of a larger common plan of development or sale totaling 1 acre or more)
- State rules below 1 acre
- No statewide rule below the 1-acre permit found; check your county and town.
- Local rules
- Cities and counties often have their own grading, land-disturbance or stormwater ordinances that can apply to smaller residential projects.
- Good to know
- Alabama lets you improve your property even if it changes how water drains, as long as you don't cause substantial damage to the neighbor below. Construction stormwater permits start at 1 acre of disturbance.
Contractor licensing in Alabama
- Statewide rule
- License
- Agency
- Alabama Home Builders Licensure Board
- Who needs it
- Builders and remodelers doing residential construction or remodeling where the job cost exceeds $10,000 must hold a Home Builders Licensure Board license.
- When it applies
- Residential jobs over $10,000 (roofing jobs over $2,500)
- Check a contractor
- Official lookup
- Licensed separately
- Plumbers, HVAC contractors and electricians must be state-licensed regardless of job cost.
- Good to know
- Commercial work is licensed by a separate agency, the Alabama Licensing Board for General Contractors.
Contractor license requirements in every state
Contractor deposits and your right to cancel in Alabama
- Deposit limit
- No statewide cap.
- Right to cancel
- Home solicitation sales made on credit: the buyer may cancel until midnight of the third business day after signing (Ala. Code § 5-19-12; 'home solicitation sale' is defined in § 5-19-1 as a consumer credit sale). For cash sales made at your home, the federal 3-day Cooling-Off Rule applies.
- Written contract
- Licensed residential home builders (license required for residential jobs over $10,000) must use a valid written contract that shows the builder's license number (Ala. Code § 34-14A-7(f)). Before work begins the builder must give a signed, witnessed written disclosure of whether it carries liability insurance (§ 34-14A-19).
- Other protections
- The Home Builders Licensure Board may run a Homeowners' Recovery Fund for complaints against licensees (Ala. Code § 34-14A-15).
- The law
- Ala. Code Title 34, Ch. 14A (Home Builders Licensure); Ala. Code §§ 5-19-1, 5-19-12 (home solicitation sales)
- Good to know
- Alabama's own 3-day cancel law covers home sales made on credit; for cash deals signed at your kitchen table, the federal 3-day Cooling-Off Rule still applies. Check the builder's license on any residential job over $10,000.
Contractor deposit limits in every state
Mechanics lien deadlines in Alabama
- Lien deadline (prime)
- Within 6 months after the last labor or materials furnished, for original contractors (Ala. Code § 35-11-215).
- Lien deadline (sub/supplier)
- Within 4 months after the last labor or materials furnished; 30 days for journeymen and day laborers (Ala. Code § 35-11-215).
- Preliminary notice (sub/supplier)
- Not required for a lien, but it sets the amount. Without notice, a sub's or supplier's lien is limited to the unpaid balance the owner still owes the contractor. A supplier who notifies the owner in writing before furnishing (naming the materials, the contractor and the prices) can lien for the full price unless the owner objects in writing before the materials are used (Ala. Code § 35-11-210).
- Notice of intent
- Anyone other than the original contractor must give the owner written notice of the lien claim (amount, what it is for, who owes it) before filing the lien statement. No set number of days. Not needed for materials already covered by a § 35-11-210 advance notice (Ala. Code § 35-11-218).
- Enforce within
- Suit within 6 months after the entire debt secured by the lien comes due (Ala. Code § 35-11-221).
- Homeowner rules
- Without the advance notice, a sub's or supplier's lien reaches only what the owner still owes the contractor; after a § 35-11-218 notice, the owner must hold any unpaid balance for the claimant (Ala. Code §§ 35-11-210, 35-11-218).
- The law
- Code of Alabama, Title 35, Ch. 11, Art. 5, Div. 8 (Mechanics and Materialmen), § 35-11-210 et seq.
- Good to know
- In Alabama, a supplier who wants a lien for the full price must notify the owner in writing before delivering materials; otherwise the lien is limited to what the owner still owes the contractor.
Mechanics lien deadlines in every state
Workers' comp requirements in Alabama
- Who must carry it
- Employers who regularly employ 5 or more employees, full- or part-time, must carry coverage; corporate officers and LLC members count toward the 5 (Alabama Dept. of Workforce; Workforce Alabama FAQ). The under-5 exemption does not apply to businesses in construction of new single-family detached homes, so those employers need coverage from the first employee (Alabama Dept. of Workforce).
- Owners and officers
- Corporate officers and LLC members count as employees toward the 5-employee threshold (Workforce Alabama FAQ). How owners themselves are covered or can opt out was not confirmed in an official source; ask your insurer.
- Subcontractors
- Alabama has no statutory-employer provision; the employer is the party that hires and pays wages directly (Ala. Code § 25-5-1(4)), though joint employers can be held jointly liable (per ALFA International compendium, 2025).
- Homeowners
- Domestic employees are exempt from mandatory coverage (Ala. Code § 25-5-50). With no statutory-employer rule, a homeowner hiring a contractor is not made the employer of the contractor's crew under the comp law.
- Penalties
- No penalty amount published on an official source we could find. Ask the state agency.
- The law
- Ala. Code Title 25, Ch. 5 (Workers' Compensation); § 25-5-50 (exemptions incl. under-5 rule)
- State agency
- Alabama Department of Workforce, Workers' Compensation Division
- Good to know
- Alabama requires coverage once you regularly have 5 or more employees, counting part-timers, corporate officers and LLC members. If you build new single-family homes, you need coverage with even one employee.
Workers' comp requirements in every state
Planting zones in Alabama
- 2023 USDA zones
- 7b to 9b
- Coldest-night range
- 5°F to 30°F
- Coldest area
- Extreme north Alabama
- Warmest area
- The immediate Gulf Coast
- Example cities
- Birmingham: 8a, Huntsville: 8a, Montgomery: 8b, Mobile: 9a
- Good to know
- Alabama shifted about a half zone warmer on the 2023 map; most of the state is now zone 8, with zone 9 along the coast.
Frost dates in Alabama
| Station | Last spring frost | First fall frost | Frost-free days |
|---|---|---|---|
| Huntsville North Alabama | March 24 | November 8 | 229 |
| Birmingham North-central Alabama | March 21 | November 11 | 236 |
| Montgomery Central Alabama | March 13 | November 13 | 244 |
| Mobile Gulf Coast | March 3 | November 25 | 268 |
- Typical range
- Last frost early Mar (Mobile) to late Mar (Huntsville); first frost early Nov (Huntsville) to late Nov (Mobile)
- Good to know
- These are typical (50%) dates from NOAA's 1991–2020 climate normals, so about half of years still bring a 32°F night after the listed spring date. In Alabama, the last spring frost at the stations listed ranges from early March around Mobile to late March around Huntsville.
Frequently Asked Questions
What building code does Alabama use?
2015 International Residential Code with Alabama amendments (Alabama Residential Building Code). It applies as follows: statewide for some areas only. Your local building department can confirm the edition and amendments for your address.
How deep is the frost line in Alabama?
Frost depth is set by local building departments. Footings for houses, additions and attached decks go below it.
How much can a contractor ask for up front in Alabama?
No statewide cap. Cancel rights: Home solicitation sales made on credit: the buyer may cancel until midnight of the third business day after signing (Ala. Code § 5-19-12; ‘home solicitation sale’ is defined in § 5-19-1 as a consumer credit sale). For cash sales made at your home, the federal 3-day Cooling-Off Rule applies.
How long does a contractor have to file a mechanics lien in Alabama?
Within 6 months after the last labor or materials furnished, for original contractors (Ala. Code § 35-11-215). Subcontractors and suppliers may have different notice rules; see the section above.
What planting zone is Alabama?
On the 2023 USDA map, Alabama runs from zone 7b to 9b. Examples: Birmingham 8a, Huntsville 8a, Montgomery 8b. Enter your ZIP on the USDA map for your exact zone.
Do contractors need workers' comp in Alabama?
Employers who regularly employ 5 or more employees, full- or part-time, must carry coverage; corporate officers and LLC members count toward the 5 (Alabama Dept. of Workforce; Workforce Alabama FAQ). The under-5 exemption does not apply to businesses in construction of new single-family detached homes, so those employers need coverage from the first employee (Alabama Dept. of Workforce). Owner exemptions and subcontractor rules are in the workers’ comp section above.
When is the last frost in Alabama?
At the NOAA stations we list: Last frost early Mar (Mobile) to late Mar (Huntsville); first frost early Nov (Huntsville) to late Nov (Mobile). These are typical (50%) dates from the 1991–2020 climate normals, so about half of years still bring a 32°F night after the spring date.
This page is general information, not legal or tax advice. Rules change; the agencies and statutes linked above have the final word.
Alabama in each 50-state guide: Frost line depth · 811 dig laws · Retaining wall permits · Contractor licensing · Contractor deposit limits · Building codes · Planting zones · Mechanics lien deadlines · Workers' comp · Frost dates · Drainage laws · Noxious weed laws · Rainfall and snowfall · Landscaper pay · Pesticide applicator licensing · Landscaping sales tax · All state guides
Last checked October 31 and November 1, 2026 against official state and local sources for this state. Rules change; your state agency or local building department has the final word. Spot something out of date? Email info@muthlerlandscaping.com and we’ll fix it.
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Cite as: Muthler Landscaping & Construction, “Alabama Building Codes, Permits and Contractor Rules,” https://muthlerlandscaping.com/state-guides/alabama/ (last checked November 9, 2026).
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