Step 14 of 44Design Phase

Apply for Building Permits

With your design complete, it's time to submit your permit application. A complete submission with all required documents is the key to avoiding delays. Here's exactly what you need and how to navigate the process.

Quick Summary

Permit fees

$5,000-$20,000

Review time

4-16 weeks

Key requirement

Complete documents

Required Documents Checklist

Every city has slightly different requirements, but these documents are typically required for ADU permits. Missing any item can delay your application by weeks.

Architectural Plans

  • • Site plan showing ADU location, setbacks, property lines
  • • Floor plans with room dimensions and uses
  • • Exterior elevations (all four sides)
  • • Building sections showing ceiling heights
  • • Roof plan with drainage
  • • Door and window schedules
  • • Finish schedules (materials specifications)

Engineering Documents

  • • Structural engineering calculations (stamped)
  • • Foundation design
  • • Framing plans
  • • Soils report (if required in your area)
  • • Title 24 energy calculations (California) or energy code compliance

MEP Plans (Mechanical, Electrical, Plumbing)

  • • Electrical plan with panel size, circuits, outlets
  • • Plumbing plan with fixture locations, pipe sizes
  • • HVAC plan showing equipment and duct layout
  • • Gas piping plan (if applicable)
  • • Load calculations for electrical and HVAC

Site-Specific Documents

  • • Property survey (recent, within 5 years)
  • • Topographic survey (if site has slope)
  • • Tree survey (if protected trees exist)
  • • Drainage/grading plan
  • • Utility connection points marked

Administrative Documents

  • • Completed permit application form
  • • Property owner authorization (if not owner)
  • • Proof of property ownership (deed or title)
  • • HOA approval letter (if applicable)
  • • School district fee receipt (some areas)

Understanding Permit Fees

Permit fees for ADUs typically range from $5,000 to $20,000 depending on location and project size. Here's what makes up that total:

Fee TypeTypical RangeNotes
Plan check fee$1,000-$3,000Based on project valuation
Building permit fee$1,500-$5,000Based on sq footage
Impact fees$0-$10,000+Waived in some states for ADUs
School fees$0-$5,000Often waived for ADUs under 750 sq ft
Utility connection fees$500-$3,000Sewer, water, electrical
Technology/records fee$100-$500Administrative costs

California homeowners: State law caps ADU permit fees and eliminates many impact fees for units under 750 sq ft. Verify current fee waivers with your city.

The Submission Process

1

Prepare Your Submission Package

Organize all documents according to city requirements. Many cities now accept digital submissions—check for file format and size requirements.

  • • Verify required number of plan sets (typically 2-4)
  • • Check plan sheet size requirements
  • • Ensure all engineer stamps are current
  • • Complete all application forms fully
2

Submit and Pay Fees

Submit your application online or in person. Plan check fees are typically due at submission; building permit fees at issuance.

Tip: If submitting in person, arrive early and bring a credit card. Some cities only accept checks—confirm payment methods.

3

Track Your Application

Get your permit number and track progress online. Most cities offer portal access to see which department is reviewing your plans.

  • • Save your permit/tracking number immediately
  • • Set up email notifications if available
  • • Note the assigned plan checker's name
  • • Mark expected review completion dates
4

Respond to Plan Check Comments

Most submissions receive correction comments. Review carefully, address every item, and resubmit promptly to maintain your place in queue.

  • • Have your architect clarify unclear comments
  • • Address EVERY comment, even minor ones
  • • Reference comment numbers in your response
  • • Cloud or highlight changes on revised plans
5

Permit Issuance

Once approved, pay remaining fees and receive your building permit. Post the permit visibly on site before starting construction.

  • • Get approved plans stamped by city
  • • Keep one set of approved plans on site always
  • • Note permit expiration date (typically 1-2 years)
  • • Understand required inspection schedule

Tips for Efficient Tracking

Check status weekly

Log into the permit portal every week to catch updates early.

Build relationships

A polite call to your plan checker can provide valuable insight.

Respond within 48 hours

Fast responses to comments keep your application moving.

Document everything

Keep copies of all communications and submissions.

Common Submission Issues

Incomplete Energy Calculations

Title 24 (California) or local energy code compliance is often incomplete or doesn't match the plans. Have your energy consultant coordinate with your architect.

Setback Discrepancies

Site plan setbacks must match architectural plans exactly. Use a recent survey and triple-check all dimensions before submitting.

Missing Fire Ratings

If your ADU is within 5 feet of property line or main house, fire-rated construction is required. Specify ratings clearly on plans.

Frequently Asked Questions

Can I submit permits myself or do I need my architect?

You can submit yourself, but many homeowners have their architect handle it. They know what the city expects and can respond to technical comments. Some architects include permit coordination in their fee; others charge extra.

What if my permit expires before construction is complete?

Most permits can be renewed for a fee before expiration. If expired, you may need to reapply under current codes, which could require plan changes. Keep construction moving to avoid this scenario.

Do I need separate permits for electrical, plumbing, and mechanical?

Usually these are included in your building permit as "sub-permits." However, your contractors may need to pull these permits themselves using their licenses. Confirm the process with your city and contractors.

Ready for the Next Step?

While your permit is in review, make sure your design addresses all fire safety and building code requirements to avoid costly revisions.

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