Zoning, building permits and septic rules in Darby Borough, Pennsylvania

At a glance

Building permit

Required; issued by the borough, not the county²³

Zoning

Borough zoning chapter with published districts and map¹⁶

R-1 minimum lot

6,000 square feet (single-family detached)⁷

R-1 setbacks

Front 30 ft, side 25 ft total (10 ft minimum), rear 25 ft⁸

R-1 coverage and height

30% building, 50% impervious; 35 ft or 2 stories⁹¹⁰

Septic and wells

Delaware County Health Department for the county; Darby-specific agency unconfirmed⁵¹¹

Who to call

Contact details are copied from each office’s official page and were checked against it on October 24, 2026.

Does Darby Borough have zoning, and what does it mean for lot size and setbacks?

Yes. Darby Borough adopted its own zoning chapter, and the borough's code identifies that chapter as its zoning law¹. The district schedule and zoning map are published with the chapter⁶, and the borough posts its zoning ordinance and map on its Codes page¹². Delaware County does not zone for the borough; it points readers to municipal officials for current zoning¹³.

In the R-1 Residential District, a single-family detached house needs a lot of at least 6,000 square feet⁷. Setbacks there are 30 feet in front (15 feet on the long side of a corner lot), 25 feet total for side yards with a 10-foot minimum, and 25 feet in the rear⁸. Buildings may cover 30% of the lot and impervious surface 50%⁹, and height tops out at 35 feet or 2 stories¹⁰. Other districts have different numbers, so confirm your parcel's district on the borough map before you plan anything.

Do you need a building permit in Darby Borough, and who issues it?

Yes. Pennsylvania's Uniform Construction Code requires an owner to get a building permit before starting construction, alteration, repair or a change of occupancy on a residential building, and before regulated electrical, gas, mechanical or plumbing work¹⁴. Darby Borough has elected to administer and enforce that code itself², so the borough's Codes Department is the office to call¹⁵. Delaware County does not issue building permits and sends questions to municipal code officials³.

The borough's Codes page posts separate applications for building, electrical, plumbing, mechanical and demolition permits, and for certificates of occupancy¹². Fees are set by Borough Council resolution, so ask the Codes Department for the current schedule¹⁶. Pennsylvania also requires a certificate of occupancy before a residential building can be used¹⁷.

How do septic permits and wells work inside Darby Borough?

The Delaware County Health Department processes and issues permits for individual and small-community on-lot sewage systems and for well construction in Delaware County⁵. A permit is required for new systems, repairs and modifications, except repairs that need no digging equipment¹⁸. The department's Environmental Health office is the one to call¹⁹.

We could not confirm which local agency handles on-lot sewage for an individual address inside Darby, or whether a given lot is on public sewer, so ask the Health Department and the borough Codes Department before you rely on any septic plan. Pennsylvania law bars occupying a building served by an onlot system without a permit from the local agency²⁰. Private wells are permitted through the county Health Department¹¹.

Can you live in an RV or tiny home in Darby Borough?

We could not confirm a Darby Borough rule on long-term RV living, temporary camping, tiny homes or accessory dwellings. The pages we reviewed did not show an operative provision for any of them, which is not the same as permission. Pennsylvania's rules for state park campgrounds do not answer the question for private land²¹.

Because Darby zones its own land¹, the answer sits in the borough zoning ordinance for your district. Ask the borough office before buying or parking anything for stays¹², and get the answer in writing.

Building a home in Darby Borough: the steps, in order

1. Find your parcel's zoning district on the borough zoning map and check lot size, setbacks, coverage and height⁶.
2. Ask the Codes Department whether the lot is in a floodplain; the borough requires a floodplain permit before any construction or development²², applied for in writing to the Floodplain Administrator on borough forms²³.
3. Get zoning approval, which can involve a zoning hearing or conditional use application¹².
4. Apply for the building permit and trade permits from the borough¹⁵.
5. Confirm septic or sewer with the Delaware County Health Department¹⁹.
6. If the lot fronts a state highway, expect a PennDOT highway occupancy permit for the driveway²⁴.
7. Pass the required inspections, then obtain the certificate of occupancy²⁵²⁶.

What stays with Delaware County, and what to check before you buy in Darby

Septic and well permits sit with the Delaware County Health Department⁵. Subdividing a lot goes through the county Planning Commission's review and then municipal approval²⁷; building permit questions go to the municipality's code officials, not the county²⁸. For land outside the borough, see the Delaware County page.

Darby is dense and close to a major city: the county averages about 3,138 people per square mile²⁹. Delaware County's effective property tax rate is 2% and the median bill is $6,001 a year³⁰³¹, and the nearest city of 100,000 or more is about 16 miles from the county center³². Because Darby is a built-out borough, a purchase is usually a teardown, infill or renovation project rather than raw land, so ask for a zoning verification and a flood check before closing.

Watch-outs

• Darby Borough is separate from Darby Township, also in Delaware County, and a search for Darby permits often returns the township's pages; use the Borough of Darby Codes Department¹⁵.
• We could not confirm Darby Borough rules on owner-built homes, accessory dwelling units, driveways or short-term rentals, so ask the Codes Department before relying on any of them¹⁵.
• Floodplain construction needs a borough permit before any work starts, even for projects that otherwise look minor²².

Sources

1. Chapter 153: Zoning - Borough of Darby, PA (Borough of Darby), quoted and re-checked
2. Chapter 59: Construction Codes, Uniform - Borough of Darby, PA (Borough of Darby), quoted and re-checked
3. Delaware County Planning Department - Development Review (2026 county census)
4. Delaware County Planning Department - Development Review (2026 county census)
5. Sewage and Water, quoted and re-checked
6. Chapter 153: Zoning - Borough of Darby, PA (Borough of Darby), quoted and re-checked
7. Appendix B, Bulk and Area Requirements for all Zoning Districts (Borough of Darby), quoted and re-checked
8. Appendix B, Bulk and Area Requirements for all Zoning Districts (Borough of Darby), quoted and re-checked
9. Appendix B, Bulk and Area Requirements for all Zoning Districts (Borough of Darby), quoted and re-checked
10. Appendix B, Bulk and Area Requirements for all Zoning Districts (Borough of Darby), quoted and re-checked
11. Sewage and Water, quoted and re-checked
12. Borough of Darby (borough hall) (darbyborough.com)
13. delcopa.gov, quoted and re-checked
14. Apply for a Uniform Construction Code Building Permit, quoted and re-checked
15. Borough of Darby Codes Department (darbyborough.com)
16. Chapter 59: Construction Codes, Uniform - Borough of Darby, PA (Borough of Darby), quoted and re-checked
17. pa.gov, quoted and re-checked
18. Permits for On-Lot Sewage Disposal Systems, quoted and re-checked
19. Delaware County Health Department, Environmental Health (delcopa.gov)
20. 25 Pa. Code § 72.22. Permit issuance (Pennsylvania statewide rule), quoted and re-checked
21. RV and Tent Campsites (Pennsylvania statewide rule), quoted and re-checked
22. Chapter 77, Article III: Administration - Borough of Darby, PA (Borough of Darby), quoted and re-checked
23. Chapter 77, Article III: Administration - Borough of Darby, PA (Borough of Darby), quoted and re-checked
24. pa.gov, quoted and re-checked
25. Uniform Construction Code Chapter 403, quoted and re-checked
26. Uniform Construction Code Chapter 403, quoted and re-checked
27. Development Review, quoted and re-checked
28. Development Review, quoted and re-checked
29. Population density: Bolthole Index county data
30. Effective property tax rate: Bolthole Index county data
31. Median property tax bill: Bolthole Index county data
32. Straight-line distance from the county center to the nearest city of 100,000+ people: Bolthole Index county data

Written October 24, 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.