Commercial Tenant Improvements

The following information shall apply to the construction, alteration, relocation, enlargement, change of use and occupancy, replacement, repair, equipment installation, and demolition work associated with tenant improvements and build-outs and within the scope of the International Building Code. (IBC)

How to Prepare

A Pre-Application Meeting and Intake Screening are typically not required for tenant improvement projects but are available at the applicant’s request. Discuss submittal requirements with a Permit Coordinator, discuss design criteria unique to Mercer Island Land Use Code with a Land Use Planner, and discuss IBC code requirements with a Building Plans Examiner.

1.  Check to see if the proposed use of the space is different from the previously approved land use, per the current Mercer Island Land Use Code. Talk to a Planner if you have questions and consider:

2.  Talk to a Planner about Design Review Requirements and consider:

  • Exterior modifications require Design Review Approval - this includes those modifications associated with updated mechanical equipment, etc.
  • Signage requires Design Review Approval (Building permit and electrical permit may also be  required).
  • Design Review is a Land Use Approval - For information about how to submit a Design Review Application click here.
  • Permit Review Timelines for Design Review (Land Use Decisions).

3.  Work with subcontractors early to prepare submittals for Mechanical, Electrical, and Plumbing review. Anticipate the review timelines involved. The first plan review for most trade permit submittals is routed with a two week timeline. Allow two weeks for review of subsequent re-submittals. 

Applicable Design Codes
 

Required Forms - Building Permit Submittal

  1. Building Permit Application
  2. Fire Square Footage Calculation—Commercial
  3. Transportation Concurrency Application

Required Documents - Building Permit Submittal

This document list should not be considered comprehensive. It is the applicant’s responsibility to justify and provide information adequate to fully describe the scope and construction of the work.

  • Architectural Drawings:
    • Project Code Information
    • Floor and Roof Plan(s)
    • Typical Wall Section(s)
    • Accessibility Information
    • Architectural Details
    • Other information as necessary to fully describe the scope of work

Required Supplemental Information (as applicable):

  • Additional Architectural Drawings:
    • Architectural Site Plans
    • Demolition Plans
    • Means of Egress Information
  • Structural Drawings (if necessary):
    • General Structural Notes, including design criteria, materials, project responsibilities, etc.
    • Floor Framing Plans
    • Roof Framing Plans
    • Structural Details
    • Statement of Special Inspections
  • Structural Calculations keyed to the construction documents
  • Project Energy Efficiency Calculations and Building Envelope Energy Code Compliance Forms.
  • Lighting Power Allowance Calculations.
  • List of Fire Protection Systems contained in the building (Fire Sprinkler System, Fire Alarm System, Hood Cooking Suppression System).
  • Location, type and model of grease interceptor

Please note:

  • Projects shall be prepared and sealed by a Washington State licensed design professional if the project includes any of the following:
    • A project size more than 4,000 square feet (or combined square footage of more than 4,000 square feet of simultaneous projects in the same building).
    • An alteration to the means of egress, including accessibility and barrier free provisions.
    • An alteration of fire-rated construction.
    • An increase in occupant load.
  • When King County Public Health (food service establishments) or Washington State Health (healthcare facilities) approval is required, the Construction Documents shall correspond with the documents submitted to the appropriate Public Health Organization.
  • Separate Mechanical, Electrical and Plumbing (MEP) permits are required, and if included with the Building Permit submittal, will not be reviewed. 
  • Separate Fire Protection TI Permits may be needed depending on scope and if included with the building permit will not be reviewed. More information about Fire Protection Permits can be found here.

How to Apply

Submit your plans, forms, and supplemental documents to the Mercer Island Permit Submittal Portal.