Accessory Dwelling Units (O05)
Accessory dwelling units (ADUs) add rental income, multigenerational space, and long-term property value – but in Utah they live or die on permitting, egress, and utility connections, so plan those before you build.
This BidScope guides you through ADU types: internal/basement ADUs (converting existing basement space), garage conversion ADUs (turning an attached or detached garage into a dwelling), and detached new-construction ADUs (a standalone unit in the yard). It walks the full path from feasibility to occupancy.
Learn planning and permitting – the make-or-break phase: Utah’s statewide internal-ADU law versus each city’s specific zoning rules, owner-occupancy and parking requirements, setbacks and lot coverage, maximum size limits, impact and connection fees, HOA approval where applicable, and the building-permit and inspection sequence.
Understand basement ADUs: code-compliant egress windows and wells, minimum ceiling height, a separate exterior entrance, sound and fire separation from the main dwelling, dedicated or sub-metered utilities, and a compliant kitchen and bath.
Master garage conversions: insulating uninsulated walls and slab, raising the slab or addressing the foundation, adding heating and cooling, replacing the garage door with a code wall and windows, and moisture and egress detailing.
Navigate detached new construction: foundation, framing, and full utility runs (water, sewer, power, gas), site drainage, and design that fits the lot and neighborhood.
Understand Utah-specific factors: municipal rules that vary widely between cities, radon testing and mitigation for basement units, high-water-table and expansive-soil considerations, and impact fees that can materially change the budget.
Calculate typical costs: basement ADU $40,000-100,000, garage conversion $60,000-120,000, detached new construction $150,000-350,000+ depending on size, finishes, and utility distance.
This BidScope ensures your ADU is scoped for the right type, permitted correctly for its Utah jurisdiction, and built with compliant egress, separation, and utilities.
What’s Included:
- ADU types (internal/basement, garage conversion, detached new construction)
- Planning and permitting (Utah state law vs local zoning)
- Owner-occupancy, parking, setbacks, size limits
- Impact/connection fees and HOA approval
- Building permit and inspection sequence
- Basement ADU (egress windows/wells, ceiling height, separate entrance)
- Fire and sound separation from main dwelling
- Dedicated or sub-metered utilities; compliant kitchen and bath
- Garage conversion (insulation, slab/foundation, HVAC, wall replacement)
- Detached new construction (foundation, framing, full utility runs, drainage)
- Radon testing/mitigation for basement units (Utah)
- High-water-table and expansive-soil considerations
- ADU type tracker and project metrics
- Cost factors ($40k-100k basement, $60k-120k garage conversion, $150k-350k+ detached)
