Bolthole Index

New Haven County, Connecticut

Building permits, zoning and land rules in Derby, Connecticut

Derby, Connecticut requires a city building permit before construction or alteration, and Derby administers its own zoning.12 In New Haven County, Derby buyers also need a wastewater answer: city sewer-connection rules can control whether septic is an option, while septic permits follow Connecticut’s local-health and state-agency requirements.34

At a glance

Building permits
Derby Building Official; obtain the required permit before work begins1
Zoning
City zoning; lot area and setbacks depend on the district256
Sewer connection
Required for qualifying abutting properties when sewer is within 100 feet of the property line, within 90 days after official notice3
Septic permits
Local Director of Health for systems up to 10,000 gpd; DEEP for larger systems and alternative treatment4
Owner-builder
Owners may apply; building permits and code compliance still apply7
Private wells
Local health approval before construction; nearby community water can restrict well permits8

Who to call

Building permits

Derby Building Department

Building permit applications and building inspections

203-736-1481

Online permits →

Zoning

Derby Zoning Enforcement Office

Parcel zoning questions and zoning enforcement

203-736-1481

[email protected]

Septic permits

Naugatuck Valley Health District

Local health contact for Derby septic and private-well questions

(203) 881-3255

98 Bank Street Seymour, CT 06483

Septic permits

Naugatuck Valley Health District — Septic Applications

Soil evaluation, septic plan review and permit-to-construct forms

Contact details are copied from each office’s official page and were checked against it on October 12, 2026.

Off-grid gear

Going off-grid in Derby means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Derby, CT?

Derby requires an application to the Building Official and an issued building permit before a building or structure is constructed or altered.1 Derby’s Building Official reviews plans for compliance with the Connecticut State Building Code; applicable fire-safety review is a separate part of the process.9

A Derby homeowner may apply for the building permit, but applying as an owner does not waive zoning, code, inspection or certificate-of-occupancy requirements.7 Connecticut’s code exempts specified minor work from building permits, so ask the Building Department which exemption, if any, covers your exact project before starting.10

Who issues Derby building permits, and what do they cost?

Start a Derby building permit application with the Derby Building Department, which links to an online application portal.11 Call 203-736-1481 at least 48 hours ahead when you need a specific building official’s attention.11 Derby lists inspections on Tuesdays and Thursdays, 10:00 am–12:00 pm; arrange the inspection schedule with the department.12

Derby’s published 2022 fee schedule charges $20 for the first $1,000 of estimated cost, $15 for each additional $1,000, and a state fee of $0.26 per $1,000.13 Estimated cost includes parts, materials and labor, and the schedule says zoning fees, property taxes and WPCA must be paid in full before applying.13 Ask the department to confirm the current total before budgeting from that older schedule.

Does Derby have zoning, and what are the lot sizes and setbacks?

Derby has its own zoning regulations; the parcel’s district determines the applicable dimensional rules.25 In Derby’s R-1 district, the listed lot area is 40,000 square feet and minimum width is 175 feet measured at the required front-yard setback.14 R-1 principal-building setbacks are 50 feet front, 75 feet rear and 25 feet side; accessory structures have separate side and rear requirements.15

Derby’s R-5 rules list 7,500 square feet of lot area, 75 feet of width at the front-yard setback, and 5,000 square feet of minimum lot area per family.16 Ask Derby’s Zoning Enforcement Office at [email protected] to identify the parcel’s district and review the proposed layout.17

How do sewer connections and septic permits work in Derby?

For a Derby property used for occupancy or other covered purposes that abuts a street, alley or right-of-way containing a city sewer, connection is required at the owner’s expense when the sewer is within 100 feet of the property line, within 90 days after official notice.3 Derby’s wastewater ordinance prohibits private disposal facilities except as otherwise provided in the sewer chapter, so do not assume buying land creates a right to install septic.18

Naugatuck Valley Health District serves Derby and provides soil-evaluation, septic-plan-review and construction-approval forms.1920 Connecticut assigns septic systems of 10,000 gpd or less to the Local Director of Health, with DPH plan approval for flows between 2,000 and 10,000 gpd; larger systems and alternative treatment systems go to DEEP.4

Can you live in an RV or tiny home on land in Derby?

We could not confirm Derby’s rules for residential RV occupancy, private-land camping or tiny-home occupancy; ask the city’s Zoning Enforcement Office about the proposed use and the Building Department about the proposed structure.1711 Ask specifically about living on the parcel while a permanent home is under construction, rather than asking only whether an RV may be parked there.

For a tiny home in Derby, municipal zoning and applicable building-code review remain separate questions, and a required sewer connection can affect the sanitation plan.293 We also could not confirm a Derby-specific minimum dwelling size or accessory-dwelling rule; take the proposed floor plan and parcel details to those city offices.

Building a home in Derby: what are the steps, in order?

  1. Ask Derby’s Zoning Enforcement Office to identify the parcel’s district and review lot area, width and setbacks for the proposed home.1756
  2. Resolve Derby’s sewer-connection requirement before designing a private wastewater system; if septic is an option, contact Naugatuck Valley Health District for soil evaluation and plan review.320
  3. Submit construction plans to Derby’s Building Official and, where applicable, the local fire marshal concurrently.21
  4. Obtain the building permit before construction; Derby’s published process calls for issuance or refusal within 30 days after application.1
  5. Schedule building inspections with the Derby Building Department.11

What should you check before buying land in Derby?

A private well in Derby needs local-health siting and approval before construction, and Connecticut restricts well-drilling permits for human-consumption premises when community water is deemed available within 200 feet of the parcel boundary, unless an exception is granted.8 Naugatuck Valley Health District is Derby’s local health contact; ask the district how that rule applies to the address.19

Ask Derby’s Building Department and Zoning Enforcement Office to identify any floodplain, wetlands or driveway approvals needed for the proposed work; we could not confirm a complete Derby-specific approval path for those issues.1117 For land outside Derby, use the New Haven County guide as a starting point, then identify the municipality before relying on a zoning answer: Connecticut municipalities exercise zoning authority within their own boundaries.5

Watch-outs

  • Derby’s R-1 and R-5 lot requirements differ; do not apply a district’s dimensions to a parcel in another district.1416
  • Owner application for a Derby building permit does not waive building-code, zoning or inspection requirements.7
  • Derby’s published building fee schedule is labeled 2022; ask the Building Department to confirm current charges.13
  • We could not confirm residential RV or tiny-home occupancy in Derby; ask the Zoning Enforcement Office before committing to either plan.17

Sources

  1. Building Plan Review (Derby), quoted and re-checked
  2. Chapter 195: Zoning - City of Derby, CT (Derby), quoted and re-checked
  3. Chapter 154: Sewers - City of Derby, CT (Derby), quoted and re-checked
  4. Subsurface Sewage Disposal Systems (Derby), quoted and re-checked
  5. Connecticut General Statutes, Chapter 124—Zoning, § 8-2 (Connecticut statewide rule), quoted and re-checked
  6. Connecticut General Statutes, Chapter 124—Zoning, § 8-2 (Connecticut statewide rule), quoted and re-checked
  7. Building (Connecticut statewide rule), quoted and re-checked
  8. Private Wells (Connecticut statewide rule), quoted and re-checked
  9. Building Plan Review (Derby), quoted and re-checked
  10. 2022 Connecticut State Building Code (with Errata #1) (Connecticut statewide rule), quoted and re-checked
  11. Derby Building Department (derbyct.gov)
  12. Building Department (Derby), quoted and re-checked
  13. City of Derby Building Department Fee Schedule (Derby), quoted and re-checked
  14. Article III: Zoning Districts and District Requirements - City of Derby, CT (Derby), quoted and re-checked
  15. Article III: Zoning Districts and District Requirements - City of Derby, CT (Derby), quoted and re-checked
  16. Article III: Zoning Districts and District Requirements - City of Derby, CT (Derby), quoted and re-checked
  17. Derby Zoning Enforcement Office (derbyct.gov)
  18. Chapter 154: Sewers - City of Derby, CT (Derby), quoted and re-checked
  19. Naugatuck Valley Health District (nvhd.org)
  20. Naugatuck Valley Health District — Septic Applications (nvhd.org)
  21. Building Plan Review (Derby), quoted and re-checked

Written October 12, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Answers from the rulebook for Derby

Derby’s own rules

  • Building permitRequired

    Construction or alteration of a building or structure inside Derby city limits.

    • The application must be filed with the Building Official.
    • The permit must be issued before construction or alteration begins.
    • The permit must be issued or refused within thirty days after application.
    • The application must be made by the owner or authorized agent.
    • Registered contractors must provide the required registration information and certificate.

    permit decision deadline: 30 days (after the date of application)

    “no building or structure shall be constructed or altered until an application has been filed with the building official and a permit issued.”
  • InspectionsLimited

    Building inspections administered by Derby's Building Department.

    • The official city page states that inspections are conducted on Tuesdays and Thursdays from 10:00 a.m. to 12:00 p.m.; the page does not specify every inspection stage or exemption.

    inspection days: Tuesday and Thursday · inspection hours: 10:00 am-12:00 pm

    “Inspections are conducted on Tuesdays and Thursdays between the hours of 10:00 am - 12:00 pm”
  • Local zoningPresent

    Land inside Derby city limits; Derby adopts and administers its own zoning regulations.

    • The zoning chapter was adopted by the Planning and Zoning Commission of the City of Derby on January 18, 2000; amendments are noted where applicable.
    “[HISTORY: Adopted by the Planning and Zoning Commission of the City of Derby 1-18-2000. Amendments noted where applicable.]”
  • Off-grid sanitationProhibited

    Privies, privy vaults, septic tanks, cesspools, and other wastewater-disposal facilities inside Derby where the ordinance applies.

    • The prohibition is stated as subject to later provisions of Chapter 154.
    • Where a public sewer is within 100 feet of the property line and official notice is given, direct connection is required.
    “Except as hereinafter provided, it shall be unlawful to construct or maintain any privy, privy vault, septic tank, cesspool or other facility intended or used for the disposal of wastewater.”
  • Mandatory utility hookupSewer (with conditions)

    Properties used for human occupancy, employment, recreation, or other purposes inside Derby that abut a street, alley, or right-of-way containing a city public sanitary or combined sewer.

    • Connection is required at the owner's expense.
    • The owner must connect within 90 days after official notice.
    • The public sewer must be within 100 feet of the property line.
    • The ordinance separately prohibits private privies, septic tanks, cesspools, or other wastewater-disposal facilities except as otherwise provided.

    connection deadline: 90 days (after official notice) · public sewer distance: <= 100 feet from property line

    “The owner(s) of all houses, buildings or properties used for human occupancy, employment, recreation or other purposes [...] is hereby required at the expense of the owner(s) to install suitable toilet facilities therein and to connect such facilities directly with a proper public sewer [...] within 90 days after date of official notice to do so, provided that said public sewer is within 100 feet (30.5 meters) of the property line.”
  • Permit feesPublished

    Derby Building Department permits and related certificates.

    • The fee schedule is labeled 2022 and should be checked for subsequent amendments.
    • Fees are based on the total estimated cost including all parts, materials, and labor.
    • Zoning fees, property taxes, and WPCA must be paid in full before applying for a permit.
    • A fire watch required by city ordinance must be paid in advance.

    first $1,000 of estimated cost: 20 USD · each additional $1,000 of estimated cost: 15 USD · state fee per $1,000: 0.26 USD · certificate of completion: 35 USD · certificate of occupancy: 50 USD · residential plan review: 50 USD

    “Building Permits 1st $1000 of estimated cost $ 20.00 each additional $1000 of estimated cost $ 15.00 State Fee based on each $1000 of estimated cost $ .26”
  • Permit processPublished

    Building permit applications and plan review inside Derby city limits.

    • Plans must be submitted to the Building Official and, when applicable, the local fire marshal concurrently.
    • The Building Official reviews for State Building Code compliance.
    • The official city page also provides building department contact and inspection scheduling information.

    permit decision deadline: 30 days (after application date)

    “In order to meet this statutory requirement plans shall be submitted to both the building official and the local fire marshal concurrently.”

Rules another office applies inside Derby

Derby does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • Building code adoptedAdopted

    Building construction and alterations inside Derby city limits are reviewed for compliance with the Connecticut State Building Code.

    • Derby's Building Official reviews plans before permit issuance.
    • Where applicable, the local fire marshal reviews plans under the Connecticut State Fire Safety Code.
    “the building official shall review the plans of buildings or structures to be constructed or altered [...] to determine their compliance with the requirements of the State Building Code”
  • Minimum lot sizeSpecified

    Single- and two-family residential development in Derby's R-5 Zone.

    • The zone also specifies a minimum lot area per family of 5,000 square feet.

    minimum lot area: 7500 square feet · minimum lot width: >= 75 feet (measured at the required front yard setback) · minimum lot area per family: 5000 square feet

    “Each lot shall have an area of 7,500 square feet and a width of at least 75 feet measured at the required front yard setback. Minimum required lot area per family: 5,000 square feet.”
    One more reviewed finding on this topic
  • SetbacksSpecified

    Single-family residential development in Derby's R-1 Zone.

    • Accessory structures have separate rear and side setback rules.

    front setback: 50 feet · rear setback: 75 feet · side setback: 25 feet

    “Minimum required front yard: 50 feet Minimum required rear yard: 75 feet. Minimum required side yard: 25 feet.”
  • Who permits septicMixed (with conditions)

    Septic systems inside Derby city limits under Connecticut's statewide allocation of permitting authority.

    • Systems with design flows of 10,000 gallons per day or less are permitted by the Local Director of Health.
    • Plans for systems serving buildings with design flows between 2,000 and 10,000 gallons per day must be approved by the Connecticut Department of Public Health.
    • Systems exceeding 10,000 gallons per day and alternative treatment systems are permitted by the Connecticut Department of Energy and Environmental Protection.

    local-health permitting threshold: <= 10000 gpd · large-system DPH approval range: 2,000-10,000 gpd · DEEP permitting threshold: > 10000 gpd (alternative treatment systems are also included)

    “Septic systems on sites with design flows of 10,000 gallons per day (gpd) and less are permitted by the Local Director of Health.”
  • Septic permitRequired

    New or altered septic systems inside Derby city limits.

    • The specific permitting authority depends on design flow and treatment type.
    • Local Director of Health, DPH, or DEEP approval applies according to the thresholds stated by CT DPH.
    “Septic systems on sites with design flows exceeding 10,000 gpd and alternative treatment systems are permitted by the CT Department of Energy and Environmental Protection.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Derby or New Haven County directly.

  • Owner-builder exemption — Owner-builder permit exemptions inside Derby city limits.
  • Minimum dwelling size — Minimum dwelling size inside Derby city limits.
  • Living in an RV — Long-term or residential occupancy of recreational vehicles inside Derby city limits.
  • Camping on your land — Temporary camping on private land inside Derby city limits.
  • Tiny homes — Tiny-home occupancy inside Derby city limits.
8 more unanswered
  • Manufactured homes
  • Accessory dwellings
  • Septic inspection
  • Well permit
  • Agricultural exemption
  • Subdividing land
  • Driveway access
  • Short-term rentals

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Unanswered questions are usually a sign that Derby publishes no rule on the point, not that none exists. New Haven County’s page lists the county offices to call.

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