Blog - Erusu Consultants

Time is money, so it’s important to understand how long the whole process to design, permit and build an accessory dwelling unit will take. The schedule is broken down into three phases, and each phase has different parameters depending on the city, the size and design of the ADU, and the intricacy of your property.

Here’s a general timeline to give you an idea of what to expect:

• Planning and Design (1-6 months):
  1. This phase includes developing the ADU’s design, obtaining necessary permits, and securing financing.
  2. The timeline can vary widely depending on the complexity of the design and the efficiency of the permitting process in your area.
• Site Preparation (2-4 weeks):
  1..This involves clearing the construction site, grading, and preparing the foundation.                                          2.The time required depends on the site’s condition and any necessary excavation work.
• Foundation (2-4 weeks):
  Constructing the foundation can take several weeks, depending on the foundation type (e.g., slab, crawl space, full basement) and local construction practices.
• Framing (4-8 weeks):
  1 The framing phase includes building the structural framework of the ADU, including walls, floors, and the roof.
  2. The timeline depends on the complexity of the design and the size of the construction crew.
• Exterior Work (4-6 weeks):
  1. This phase includes installing the exterior siding, roofing, windows, doors, and other exterior finishes.
  2. The timeline can vary based on weather conditions and the availability of materials.
• Interior Work (6-10 weeks):
  1. Interior work involves electrical, plumbing, insulation, drywall, flooring, and interior finishes.
  2. The timeline depends on the complexity of the interior design and the availability of skilled tradespeople.
• Utilities (2-4 weeks):
  1. Connecting the ADU to utilities, such as water, sewer, gas, and electricity, can take several weeks.
  2. The timeline also depends on the distance from existing utility connections.
• Inspections (Varies):
  Local building authorities typically conduct inspections at various stages of construction. The time it takes to schedule and pass these inspections can affect the overall timeline.
• Final Touches (2-4 weeks):
  1. This includes installing fixtures, appliances, and any remaining finishes.
  2. Landscaping and exterior improvements may also be completed during this phase.
• Final Inspections and Occupancy (Varies):
  1. Once all work is complete, final inspections are conducted to ensure compliance with building codes.
  2. After passing final inspections, you can obtain an occupancy permit and move into or rent out the ADU.

Depending on the intricacy of your design, the city in which you are located, and the site circumstances, the full process of planning, obtaining permits, and building an auxiliary dwelling unit (ADU) for new construction will take 10 to 18 months. According to the jurisdiction and the size of the unit, design takes around 3–4 months, permitting takes about 8–12 months, and construction takes about 5-7 months.

Disclaimer: This content is provided solely for your review. Erusu Consultants takes no liability for this article. The reader is advised to form their own opinion. Please consult a Structural Engineer before making any final decisions.