Can I build a casita (ADU) on my residential lot in Henderson?

Yes. Henderson Development Code §19.9.2.D.6 allows an accessory dwelling unit — detached, attached, or within the primary residence — on a lot with a principal dwelling. The ADU may be no larger than the greater of 25% of the principal dwelling's floor area or 1,000 sq ft (a tiny house is capped at 400 sq ft), only one is allowed per lot, and a detached ADU 14 ft or less in height has a 5 ft side/rear setback. Separately, NRS 278.257 (effective July 1, 2026) requires Henderson to authorize ADUs on single-family lots and bars Henderson from imposing owner-occupancy conditions or prohibiting separate kitchen facilities; any Title 19 condition more restrictive than the statute is superseded as of that date.

Can Henderson require me to live on the property if I build an ADU?

No. Nevada NRS 278.257(2)(e) prohibits Henderson from requiring owner-occupancy as a condition of ADU approval. Henderson may prohibit use of the ADU as transient lodging (short-term rental), but cannot require you to reside on the property.

Accessory Dwelling Unit (ADU) Permit in Henderson, Nevada

Required for construction of a new accessory dwelling unit on a residential property in Henderson, including detached casitas, attached additions, and garage conversions. Henderson's Development Code (Title 19) §19.9.2.D.6 sets the ADU standards: an ADU is a building/structure (including a tiny house) on the same lot as a principal dwelling — detached, attached, or built within the primary residence — intended for occupancy as separate living quarters. Maximum size is the greater of 25% of the principal dwelling's floor area or 1,000 sq ft (a tiny house is capped at 400 sq ft excluding lofts); only one ADU is allowed per lot. Nevada NRS 278.257 (effective July 1, 2026, applicable to cities with 60,000+ population including Henderson) additionally requires Henderson to authorize ADUs on single-family-zoned residential property and bars Henderson from imposing an owner-occupancy condition, prohibiting separate kitchen facilities, or requiring more than one additional parking space; local conditions more restrictive than the statute are superseded as of July 1, 2026. Building permit fees follow Henderson DSC Fee Schedule Table A (new detached ADU or attached addition) or Table B Dwelling Remodel (garage conversions), effective 10/01/2025.

Verified 2026-06-30 · Source

When you need this permit

ADU maximum size: no more than 25% of the principal dwelling's floor area OR 1,000 sq ft, whichever is greater; a tiny house may be no larger than 400 sq ft (excluding lofts); an attached garage is not counted toward ADU size (Henderson Development Code §19.9.2.D.6.b.ii)
No more than one ADU per lot (§19.9.2.D.6.b.iii); ADUs do not count toward maximum residential density (§19.9.2.D.6.b.iv)
Setbacks: front and corner-side setbacks must match the principal dwelling; for a detached ADU 14 ft or less in height the side/rear setback is 5 ft; an ADU taller than 14 ft must meet the principal dwelling's setbacks; a detached ADU must be at least 6 ft from other buildings or be connected to the principal structure by a roof at least 10 ft wide (§19.9.2.D.6.b.i)
Design: the ADU must be aesthetically compatible with the principal structure (materials, colors, building mass); if in a front or corner-side yard the design must match the principal structure; a rear-yard tiny house is exempt and must sit on a permanent foundation (§19.9.2.D.6.b.v)
An ADU may not be sold apart from the principal dwelling on the same lot (§19.9.2.D.6.b.vi)
ADU must meet all applicable building codes including 2024 IRC with Southern Nevada amendments; a manufactured ADU built to ANSI 119.5 must also comply with the adopted IRC (§19.9.2.D.6.b.vii)
Per NRS 278.257 (eff. July 1, 2026): Henderson may NOT require owner-occupancy as a condition of approval, may not prohibit separate kitchen facilities, may not require more than one additional parking space where existing + street parking satisfies anticipated need, and may not impose setbacks more restrictive than the primary residence — these supersede any more-restrictive Title 19 condition as of that date
Apply via DSC Online or in person at 240 S Water St

Required documents

Req
Building Permit Application
Available via DSC Online or in person at Development Services Center
Req
Construction Drawings
Full construction drawings for ADU including site plan, floor plan, elevations, and utility connections
Req
Energy Code Compliance
2024 IECC Climate Zone 3B compliance documentation

Fee schedule

Fee type	Amount	Notes
ADU — New Detached (Custom Single-Family schedule, Table A)	Varies by sq ft — plan check $2,945–$4,040; inspection $796–$2,877	Henderson DSC Fee Schedule Table A, Single-Family — Custom rates; ADU typical sizes 400–1,200 sf. Effective 10/01/2025. Exact fee depends on square footage of ADU. Plan check from $2,945 (400 sf) to $4,040 (2,000 sf); inspection from $796 (400 sf) to $2,877 (2,000 sf).
ADU — Attached Addition (Single-Family Residential — Addition, Table A)	Varies by sq ft — plan check $1,398–$1,761; inspection $389–$1,943	Table A Addition rates apply for attached ADU constructed as an addition to the primary dwelling. Effective 10/01/2025. Plan check from $1,398 (200 sf) to $1,761 (2,000 sf); inspection from $389 (200 sf) to $1,943 (2,000 sf).
ADU — Garage Conversion (Dwelling Remodel, Table B)	$817 first 200 sf, plus $211 per additional 100 sf	Table B Dwelling Remodel rate; most garage conversions are 400–600 sf. Effective 10/01/2025.

Review timeline

~10–30 business days

Typical estimate — confirm current times with the Henderson building department

Inspection process

1
Foundation
Footings and foundation before concrete pour
2
Framing
Structural framing, egress windows, and fire separation
3
MEP Rough-In
Mechanical, electrical, and plumbing rough-ins before walls closed
4
Final
All work complete, smoke/CO detectors, address posted

Tips

Henderson Development Code §19.9.2.D.6 caps an ADU at the greater of 25% of the principal dwelling's floor area or 1,000 sq ft (tiny house max 400 sq ft excluding lofts); only one ADU is allowed per lot.
Detached ADUs 14 ft tall or less get a reduced 5 ft side/rear setback; taller ADUs must match the principal dwelling's setbacks, and front/corner-side setbacks always match the principal dwelling.
If an ADU sits in a front or corner-side yard, its materials, roof, and color must match the principal structure; a tiny house in the rear yard is exempt from the match requirement but must be on a permanent foundation.
Nevada NRS 278.257 (effective July 1, 2026) requires Henderson to allow ADUs on single-family-zoned lots — Henderson cannot ban them or impose owner-occupancy conditions, and conditions in Title 19 more restrictive than the statute are superseded as of that date.
ADU permit fees are the same as for standard new construction or addition using Henderson's Table A or Table B fee schedule (no special ADU fee category); construction typically includes separate MPE permits at Table C rates.
ADUs must meet residential building codes (2024 IRC with SNBO amendments); commercial fire sprinkler requirements do not apply to ADUs per NRS 278.257(3)(b).

Frequently asked questions

Can I build a casita (ADU) on my residential lot in Henderson?: Yes. Henderson Development Code §19.9.2.D.6 allows an accessory dwelling unit — detached, attached, or within the primary residence — on a lot with a principal dwelling. The ADU may be no larger than the greater of 25% of the principal dwelling's floor area or 1,000 sq ft (a tiny house is capped at 400 sq ft), only one is allowed per lot, and a detached ADU 14 ft or less in height has a 5 ft side/rear setback. Separately, NRS 278.257 (effective July 1, 2026) requires Henderson to authorize ADUs on single-family lots and bars Henderson from imposing owner-occupancy conditions or prohibiting separate kitchen facilities; any Title 19 condition more restrictive than the statute is superseded as of that date.
Can Henderson require me to live on the property if I build an ADU?: No. Nevada NRS 278.257(2)(e) prohibits Henderson from requiring owner-occupancy as a condition of ADU approval. Henderson may prohibit use of the ADU as transient lodging (short-term rental), but cannot require you to reside on the property.

Sources & verification

Verified against official sources. Last reviewed 2026-06-30.

Fees, timelines, and adopted codes are researched from each jurisdiction's published records — see how we verify. Requirements change and vary by project, so always confirm the current details with the Henderson building department before you submit. PermitBase is an independent reference and is not affiliated with any government agency.

Other permits in Henderson

Residential Building Permit — New Construction (Custom Single-Family)Residential Addition / Remodel Permit Electrical Permit Plumbing Permit Mechanical / HVAC Permit Residential Reroof Permit Solar Photovoltaic (PV) Permit Demolition Permit Commercial Tenant Improvement Permit Swimming Pool / Spa Permit Block / Screen Wall Permit

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