White Rock

Also known as East Dallas, White Rock Lake, Forest Hills, Little Forest Hills, Casa Linda, Casa View, Old Lake Highlands, Lochwood, Lakewood, Dallas Arboretum

ADU Pass helps homeowners in White Rock — a USPS locale inside Dallas, Dallas County, Texas — navigate the permit paperwork for building an accessory dwelling unit. This locale covers 1 ZIP code.

1 ZIP code

Locale-specific ADU details

Site (parcel physics)

Slope:

Mean slope5%
Parcels over 12% slope8%

Soil:

Dominant classHouston Black clay (Vertisol, Udic Haplustert) with eastern-edge pockets of Austin silty clay
Expansive clay risk82%

Lot profile:

Median lot size9,200 sqft
Median lot width65 ft
Median existing FAR0.28
Parcels with alley access55%
Flag-lot parcels4%

Geo-hazards:

Seismic designationA
Parcels in FEMA SFHA13%
Bedrock depth (median)22 ft
Groundwater depth (median)18 ft

Recent ADU permit activity

Window12 months ending 2024-12-31
Approved / withdrawn / denied0 / 0 / 0

Utility capacity (upgrade likelihood)

Housing stock age:

% built pre-196062%
% built pre-198085%
Median year built1,952

Electric service drop:

% overhead service75%
Panel-upgrade likelihood50%

Sewer lateral:

Replacement likelihood45%
Typical replacement cost$8,500

Water pressure:

ZoneDallas Central Pressure Zone (lake-adjacent service)
Typical PSI52 psi
Sprinkler trigger PSI40 psi

Gas availability: available — Full gas service available throughout White Rock via Atmos Energy Mid-Tex Division. Dallas has no all-electric mandate and no gas-service moratorium. Owners can freely choose gas or all-electric appliance packages.

Locale property values

Median value$575,000
Median tax$9,545/yr
Effective rate1.7%

White Rock (ZIP 75218) median home value runs roughly 1.95x the Dallas citywide median (~$295K). The locale spans a wide value range: Forest Hills proper (some parcels $1.2M-$3M+ on the lake), Little Forest Hills (mid-$600K-$900K), Casa Linda (mid-$500K-$750K), and Lochwood / Old Lake Highlands (mid-$400K-$600K). Zillow's 75218 median ran in the mid-$550Ks-$600Ks through 2024-2025; Redfin similar. Effective property-tax rate is the countywide Dallas effective rate (Dallas ISD + City + County + Dallas College + Parkland Hospital blended). The Texas Residence Homestead 10% appraisal cap (Tax Code Sec. 23.23) limits year-over-year assessed-value increases for owner-occupied primary residences.

Locale market rent

Sq ftRent
400$1,325/mo
600$1,625/mo
800$1,900/mo

Locale HOA prevalence

% parcels under HOA6%

Locale overlays (2)

  • historic-district — Forest Hills Conservation District (CD-6, adopted 1990) covers the Forest Hills subdivision on the southeast shore of White Rock Lake, bounded roughly by Garland Rd, San Rafael, Tokalon, and the lakefront. Compatibility standards apply to all new construction including detached ADUs. Little Forest Hills is NOT a formally designated Dallas Conservation District as of 2026-04, though the neighborhood association actively advocates for compatibility. · +45d · +8% cost
    CD-6 compatibility standards impose roof form (matching pitch and material of primary dwelling), massing (proportional to main dwelling), siding materials, and window patterns on ADUs. A Certificate of Appropriateness from the Dallas Landmark Commission is required before building permit issuance. CoA review typically runs 30-60 days with one pre-application conference plus one hearing. Compatibility requirements add roughly 6-10% to build cost (brick-veneer or stone match, traditional windows, custom trim). Not a prohibition; a design-standard overlay. Casa Linda, Lochwood, and the balance of ZIP 75218 are NOT inside CD-6.
  • flood-zone — FEMA Special Flood Hazard Areas along the White Rock Lake shoreline, White Rock Creek spillway, and tributary channels affect roughly 12-15% of White Rock locale parcels — a materially higher share than Lakewood because the White Rock locale wraps the lake shoreline. Affected corridors include Forest Hills lakefront parcels (Garland Rd at San Rafael), portions of Casa Linda bordering the lake's east shore, the White Rock Creek spillway channel running north from the dam, and low-elevation parcels in Lochwood near Peavy Rd. · +30d · +15% cost
    Parcels inside a mapped SFHA require an elevation certificate and compliance with the Dallas floodplain ordinance. A new ADU in Zone AE must be elevated to or above Base Flood Elevation; ground-floor or basement sleeping space is not permitted. Pier-and-beam foundations with flood-resistant lower enclosures are typical on lakefront Forest Hills parcels. Verify parcel-by-parcel via the Dallas Floodplain Viewer before scoping.

Inherited from the city

These sections come from the city page. Click through to the Dallas ADU research for details.

  • legal history
  • size range
  • permitting process & fees
  • permit forms
  • contacts
  • utilities
  • incentives
  • viability
  • pre-approved plans
  • financing
Dallas — city ADU rules and incentives

ADU legality: unclear

Texas leaves ADU regulation to local municipalities under home-rule or Dillon-rule authority. Dallas permits ADUs subject to local conditions per its zoning ordinance.

City cost envelope

$117,300 all-in for a 525 sqft ADU (permit + build). Midpoint scenario.

Permit fee bundle: $2,905 (2026-04).

City viability (selected uses)

Long-term rentalyes
Short-term rentalwith-restrictions
Home officeyes
Relative supportyes
Dallas County — county ADU rules and overlays

County regulatory overlays

Dallas County's county-level overlays apply only inside its small unincorporated footprint (under 10% of county land, primarily southeastern Dallas County). The two material overlays at county scope are FEMA-mapped Special Flood Hazard Areas administered by Dallas County Public Works under the county's floodplain ordinance, and the countywide Trinity Common Vision Program governing floodplain management along the Trinity River corridor. Inside incorporated cities — where the vast majority of Dallas County residents and ADU-candidate parcels sit — overlay administration is a city function (e.g., the City of Dallas administers its own Escarpment Zone at Dallas Development Code Art. V and its own Floodplain regulations at Div. 51A-5.100). There is no countywide WUI / wildland-fire hazard overlay of the kind seen in California or Washington; North Texas's fire-hazard regime is ESD-by-ESD rather than a county-administered WUI zone.

  • Dallas County Floodplain Management (FEMA NFIP participation) — A new ADU in a Zone AE parcel must be elevated to or above the Base Flood Elevation per the county ordinance and is generally not permitted as a basement or ground-floor sleeping space.
  • Trinity Common Vision Program — Structures including ADUs proposed within the Common Vision corridor face stricter review than FEMA NFIP alone and may require a No-Rise Certificate from a Texas-licensed engineer.
  • On-Site Sewage Facility (OSSF) jurisdiction — An ADU counts as an additional dwelling for OSSF sizing purposes, which can trigger system expansion on undersized lots and may be infeasible on very small unincorporated parcels.

County permitting (unincorporated parcels)

Dallas County regulates construction in unincorporated areas through the Department of Unincorporated Area Services (DUAS), in partnership with the Dallas County Fire Marshal's Office and Public Works. Because the county has no zoning authority (see countyOrdinance), DUAS does not restrict whether an ADU may be built — it regulates only subdivision/plat compliance, residential building-code inspection, on-site sewage (OSSF) compliance, floodplain compliance, 911 addressing, and nuisance abatement. A detached secondary dwelling on an unincorporated parcel is permitted as an ordinary residential structure through DUAS's building-permit pathway; there is no separate 'ADU permit' because there is no county use category for accessory dwellings. Unincorporated Dallas County comprises under 10% of county land area, primarily in the southeastern corner of the county. Most ADU activity in Dallas County occurs in incorporated cities (notably the City of Dallas ADU Overlay at Dallas Development Code Sec. 51A-4.510), which are governed by city-level permitting, not this section.

DepartmentDallas County Department of Unincorporated Area Services (DUAS)
AddressRecords Building, 500 Elm Street, Suite 6100, Dallas, TX 75202
Phone214-653-6565
Emaildevelopment@dallascounty.org
Texas state — ADU law and programs

State ADU law

Texas has NOT enacted a statewide ADU preemption or ADU-by-right statute. Local governments (municipalities and counties) retain full authority over ADU zoning, setbacks, parking, size limits, owner-occupancy, and permitting. Two recent housing-reform bills in the 89th Legislature (2025) touch density and zoning procedure but do NOT preempt ADU-specific local rules: SB 15 (Bettencourt, signed 2025-06-20, effective 2025-09-01) caps minimum single-family lot sizes in cities over 150,000 in counties over 300,000, and HB 24 (signed 2025-06-20, effective 2025-09-01) raises the protest petition threshold for zoning changes. A dedicated ADU-preemption bill — SB 673 (Hughes, 2025) — passed the Texas Senate on 2025-04-10 and was reported favorably by the House Land & Resource Management Committee on 2025-05-08, but died on the General State Calendar when the 89th Regular Session adjourned on 2025-06-02. In the absence of a state ADU statute, homeowners must consult the ordinance of the municipality (or the county's subdivision rules for unincorporated areas) where the lot sits.

State financing programs

Texas does not operate an ADU-specific statewide loan, grant, or forgivable-loan program comparable to California's CalHFA ADU Grant. The Texas Department of Housing and Community Affairs (TDHCA) administers the state's general housing finance programs — My First Texas Home, My Choice Texas Home, Mortgage Credit Certificates, multifamily Housing Tax Credits, the Homeowner Assistance Fund, and Housing Trust Fund awards. None target ADU construction directly, but several can apply to an ADU as part of a primary-residence purchase or refinance when program criteria are met. ADU-specific financing in Texas is primarily local: the City of Austin's ADU Loan Program (administered through Neighborhood Housing and Community Development) and a handful of smaller pilot programs are the most visible, but these sit at the city tier, not the state tier.

Federal (United States) — ADU-relevant rules and programs

Federal ADU law

The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.

Federal financing programs

Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.

Federal tax credits

There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.

Federal housing programs

HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.

ZIP Code

  • 75218

Post Office

  • 1351 N Buckner Blvd, 75218