Building a Home Addition


Step 1: Preliminary Zoning Review


A residential addition is any structure having a roof attached to the principal structure. Prior to preparing plans, make sure to review regulations for permitted setbacks, floor area ratios, and lot coverage as stated in the Residential Setback Regulations and Requirements Handout. If the residential addition is found to comply with zoning and is less than 250 sf. in area, see Step 6 - Submit For Building Permit.  

Step 2: PCDC Review 

The Community Design Review considers the compatibility of architectural and design elements of proposed improvements to the surrounding neighborhood. During Community Design Review, the improvements will be examined for compliance with design elements as outlined in the Olivette Residential Redevelopment and Design Guidelines.   

The Site Plan Review analyzes the impact of certain improvements on the surrounding neighborhood. The Site Plan Review is required for residential additions on lots that do not meet the minimum lot dimensions. Minimum lot size requirements include a lot width of 100 feet, lot depth of 150 feet, and a lot area of 15,000 square feet. 

The Concept Stormwater Management Plan Review examines impacts of Stormwater runoff and management on the subject and adjacent properties. Various techniques to manage Stormwater may be applied. Stormwater mitigation with a best management practice is necessary for those improvements adding 400 square feet of impervious improvements or more.  Review the stormwater management page and handouts.  

Step 3: PCDC Submittal Requirements

Submit the following documents for Commission Review:
  • Complete application for Commission Review
  • 1 set of plans for the residential addition (PDF version emailed to the Department of Planning and Community Development)
  • Review Fee

Step 4: PCDC Staff Review

Once submitted, staff will review the applications and plans. Comments will be forwarded to the Petitioner noting compliance with the Olivette Residential and Redevelopment Design Guidelines, Concept Stormwater Management Plan, and applicable zoning ordinances. An onsite meeting with the Petitioner, architect or engineer who prepared the plans may be required. During this time, the Petitioner should notify adjacent property owners and subdivision trustees of the proposed improvements under review.

Step 5: PCDC Consideration and Approval

Upon completion of staff review, the petition shall be forwarded to the Planning and Community Design Commission for consideration of approval during a scheduled meeting. During Commission consideration of approval, the public and Petitioner will be able to comment on the proposed improvements. The Commission has the authority to set conditions of approval.  Once the Petition is introduced at a Commission meeting, the Commission has up to 60 days to approve or disapprove a residential petition. 

Step 6: Submit For Building Permit

Plans submitted for a building permit must incorporate any conditions of approval placed by the Planning and Community Design Commission. Requirements for a building permit include:  

  1. Completed application for Building Permit.
  2. Associated fee based on estimated costs.
  3. 3-sets of construction documents prepared by a State of Missouri registered architect or engineer in compliance with the 2015 International Residential Code.
  4. Site plan of the property illustrating the existing and proposed improvements

Conversion of unfinished areas into habitable space requires a building permit. Egress must be provided for any basement finish into habitable space. 

Plans proposing modifications to an issued building permit must submit an addendum with the requirements previously mentioned. 
 

Step 7: Inspections

The required inspections and completion deposit will be identified upon the issuance of a building permit. Twenty-four hour notice is required for inspections. Separate mechanical, plumbing, and electrical permits must be obtained through St. Louis County. Residential fence permits and projects less than $7,500 do not require a completion deposit.