Dimensional standards
Extracted standards
19 individual requirements pulled out of this section’s prose, each with the sentence it came from.
Design
- Patios, decks, balconies not on sides closest to neighbors
Patios, decks, and balconies for the accessory apartment shall not be located on either of the two sides of the accessory dwelling unit that are closest to adjoining property owners.
Height
- Maximum eave heightMaximum heightThe tallest a building may be, given in feet, in storeys, or both — whichever binds first. at setbackSetbackThe distance a building must be held back from a lot line. line20 ft
or twenty (20) feet in height at the eaves at the setback line
No accessory apartment shall exceed twenty-eight (28) feet in height, or twenty (20) feet in height at the eaves at the setback line, or the highest point of the primary dwelling unit roof.
Other
- Located behind front building line
The exterior accessory apartment shall be located behind the front building line of the primary structure in the side or rear yard.
- No commencement without permits
No commencement of use of an accessory apartment shall occur until the property owner has an approved accessory apartment permit from the Town of Blacksburg and any building permits have been issued for construction related to the accessory apartment and the work completed and approved by the Town.
The square footage of the accessory apartment shall count in the calculation of floor area ratio.
- Egress window in sleeping areas
The accessory apartment shall have an egress window in any sleeping area.
- Included in lot coverageLot coverageThe share of a lot that buildings may cover, as a percentage. calculation
The underlying zoning district development standards for lot coverage that apply to the primary dwelling shall also include the accessory apartment in the calculations of this standard.
- Maximum floor area percentage of primary structure80 pct
The gross floor area of the accessory apartment shall not exceed eighty (80) percent of the gross floor area of the primary structure in which it is located. In no case shall the maximum square footage exceed 1,000 square feet.
- Maximum floor area percentage (detached)80 pct
The gross floor area of the accessory apartment may not exceed eighty (80) percent of the gross floor area of the primary structure, or a maximum 1,000 square feet of gross floor area. For a garage apartment, the gross floor area includes the square footage of the garage.
- Maximum floor area1,000 sqftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.
In no case shall the maximum square footage exceed 1,000 square feet.
- Maximum footprint of all accessoryAccessory useA secondary activity customarily incidental to the main use of the lot — a garage, a home office. structures30 pct of rear yardYardThe open space left between a building and its lot line — the space a setback creates.
The total footprint of all accessory structures (including sheds, detached garages, etc.) shall not exceed thirty (30) percent of the rear yard area.
The square footage of the detached accessory apartment shall not count in the calculation of floor area ratio.
- Occupancy standards per underlying districtZoning districtA mapped area with one set of rules, identified by a code like R-1 or B-2.
Occupancy standards are set forth in the underlying zoning district regulations.
All accessory apartments subject to these Use and Design Standards shall be registered through the accessory apartment permit program pursuant to Zoning Ordinance § 1271 and meet all requirements in this section.
- Smoke detectors required
The accessory apartment shall have working smoke detectors in each room of the apartment. Carbon monoxide detectors are required with the use of gas heating or appliances.
Parking
- Off-street parkingMinimum parkingThe number of off-street spaces a development must provide before it may open. not required
Off-street parking is not required for the accessory apartment. If any parking is proposed, the parking shall be of a pervious surface such as pervious pavers, pervious concrete or other pervious material as approved by the Zoning Administrator.
Setback
- Comply with districtZoning districtA mapped area with one set of rules, identified by a code like R-1 or B-2. setbacksSetbackThe distance a building must be held back from a lot line.
Setbacks for the accessory apartment shall comply with setbacks for the zoning district.
- SetbacksSetbackThe distance a building must be held back from a lot line. on public street frontages
The setback requirements of the underlying zoning district shall be met on all public street frontages. However, if the accessory apartment is not located in a yard adjacent to a public right of way the minimum setbacks shall be as follows: [table omitted]
From the ordinance
No accessory apartment shall exceed twenty-eight (28) feet in height, or twenty (20) feet in height at the eaves at the setback line, or the highest point of the primary dwelling unit roof.