ADUs are allowed in BlacksburgTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Blacksburg, VA
Is your property eligible for an ADU?
# of Properties
9,265
Owner-occupied
49%
Zoning districts
26
Avg Home Value
$506,567
Median Lot Size
0.24 acres
Avg Income
$86,135
Residential Types:
9,265 housing units
Single Family
95%
Apts (4+ units)
5%
Zoning Districts:
11,585 parcels · 26 districts
R-4
33%(3,857)
PR
18%(2,110)
R-5
11%(1,273)
RR-1
8%(969)
Other
29%(3,376)
ADU Rules
What can you build in Blacksburg, VA?
Blacksburg, VA follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: By Right
- –Detached ADU: By Right
Interior / Attached ADU Size Limits
- –Maximum size of 80% of the gross floor area of the primary structure
- –Absolute maximum size of 1,000 sq ft
Detached ADU Size Limits
- –Maximum size of 80% of the gross floor area of the primary structure
- –Maximum size of 1,000 sq ft of gross floor area
Max Units
- –1 accessory apartment per lot on detached single-family lots.
- –0 ADUs allowed on duplex, multifamily, or any lot without a detached single-family home.
- –JADUs: none specified.
Owner Occupancy
- –Owner must occupy the property on-site for nine months yearly.
Parking
- –0 spaces per ADU; parking must be on a pervious surface; in Historic/Design Overlay, parking may require a CUP and must meet placement/driveway standards
Rental Restrictions
- –Permit required to rent; annual renewal; the permit does not run with the land.
- –Rentals may be by the unit only (no bedroom-by-bedroom leasing).
- –Short-term rentals prohibited; owner on-site <9 months may prohibit renting that year.
ADU State Law
What can you build in Virginia?
- –Virginia does not have a statewide ADU mandate; ADU rules are set by individual municipalities.
- –Building/fire codes are set statewide, but whether an ADU is allowed is local zoning.
- –SB 304 would have mandated ADUs. It passed the Virginia Senate in 2024 but was continued/left in House committee (i.e., not enacted statewide)
What's allowed on your lot?
These are the municipality-wide rules. What's allowed on a specific property also depends on state laws, setbacks, floor area ratio, lot coverage, environmental constraints, topography, and other property-specific factors. Search your address on FutureLot to see what's allowed on your property.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs
Is your property eligible for an ADU?
ADU rules in other Virginia municipalities
Rules change at the town line. Check the municipality your property is actually in.
Montgomery County