Basement remodeling in St. Louis: Plan and Hire

Define the room and inspect the unfinished space

Give each bidder the same description of how you want to use the basement. Mark the proposed rooms, bathroom fixtures, storage and utility access on a sketch. Ask the contractor to measure the space and explain how the design would accommodate stairs, ceiling obstructions, heating equipment and any proposed sleeping area.

For a bedroom or separate living arrangement, ask the permit office to confirm the requirements for your address and proposed use before you choose a layout. Have the contractor identify any window-opening or structural changes in the bid. The City requires permits for basement conversion, partition changes in habitable or occupiable space, and work involving structural beams or bearing support. [1]

Walk through the basement with each bidder. Point out stains, previous repairs, floor drains and places where water entered. Request a written investigation and repair scope for unresolved problems. Keep those items separate from flooring, wall finishes and cabinets so you can decide what must happen before finishing begins.

Investigate sewer backups before commissioning plumbing

MSD distinguishes problems in public sewer lines from failures in the private lateral connecting a home to the street. Its insurance programs do not cover building backups caused by a faulty residential lateral. If you have a backup history, gather prior reports and ask MSD and your plumber to clarify the cause before accepting a prevention proposal. [4]

For properties with a history of backups resulting from MSD issues, MSD offers a Sewer Separation Program that pays for plumbing modifications and provides ongoing maintenance and repair of installed devices. Ask MSD about eligibility before authorizing a private installation. MSD does not reimburse private-plumber services or services that its Customer Care Center did not initiate. [3]

Review sewer-backup coverage with your insurance agent before investing in finished space. MSD advises homeowners to verify coverage and consider a sewer-backup rider. Ask your agent to explain the coverage and limits in your own policy, then retain that explanation with your project records. [4]

Assign permits and approvals in the contract

The City's building-permit process applies to property inside St. Louis City. Confirm the governing authority for your address before using these instructions. For a City application, prepare the project address, plans and a $25 application fee. An applicant who is not the owner of record needs an owner authorization letter. [2]

You can apply online or bring drawings to the City Hall permit office. The City requests five copies of plans for an in-person submission. Write down who will prepare drawings, submit the application, respond to review comments and pay the fees. Include responsibility for applicable trade permits. [2]

The City collects the application fee when you file and the permit fee after final approvals, when the permit is ready for issuance. After approval and payment, you can print the permit for display onsite. Ask the contractor to tie the construction start to permit issuance and identify inspection responsibilities in the schedule. [2]

Compare bids by scope and payment milestones

Request separate amounts for investigation and repairs, demolition, framing, trade work, finishes and permit handling. Ask bidders to identify exclusions and finish allowances. If one contractor includes a bathroom and another excludes underground plumbing, request revised bids before comparing totals.

The fee chart shows the City's published combined application and building-permit fees for its three lowest construction-value bands. These figures are municipal charges, not basement-remodel prices. For estimated construction costs above $3,000, the City lists a $25 application fee plus $10 per thousand dollars of estimated construction cost or fraction thereof. Confirm the calculation for your project during application. [2]

Request proof of insurance, the names of the people managing trade work, and references for projects with a similar scope. Agree on written payment milestones and change-order approval. Before signing, ask who will protect the stairs and occupied rooms, remove debris, and restore access to equipment after construction.

City building-permit fees by estimated construction cost

Choose the next step before accepting a bid

Your hiring checklist

1. Write down the intended room uses and give each bidder the same sketch.
2. Gather photographs and records of past leaks, backups and repairs.
3. Request a separate investigation and repair scope before choosing finishes.
4. Confirm the permit authority for the property address.
5. Assign drawings, applications, fees and inspections in the contract.
6. List finish allowances, exclusions and trade-work responsibilities.
7. Agree on payment milestones, written changes and completion documents.

Frequently Asked Questions

Do I need a permit to finish my basement?

Within St. Louis City, converting a basement or below-grade space to living quarters requires a building permit. The City also lists partition changes and structural work as permit-triggering work, with separate trade permits when applicable. Ask the Permit Section about your exact scope. [1]

Can I apply for the building permit myself?

The City accepts owner applications online or in person. Prepare the address, project plans and $25 application fee. If someone else applies, provide an owner authorization letter. In-person submissions require five plan copies. [2]

Will MSD pay for sewer-backup protection?

MSD's program serves properties with a history of backups resulting from MSD issues. Contact MSD to determine eligibility before authorizing work. It does not reimburse private-plumber services or services that its Customer Care Center did not initiate. [3]

How should I compare remodeling estimates?

Give bidders the same layout and finish choices. Request separate prices for repairs, construction, trade work and permit handling. Ask each contractor to explain exclusions, allowances and the process for approving changes before you compare totals.