Can you build your own house in Illinois without a contractor’s license?

Illinois’s homeowner exemption covers plumbing in a qualifying single-family home¹. You can use it to plan, install, alter or repair the plumbing system yourself¹. The Illinois plumbing exemption does not establish a general exemption for every construction trade¹.

We could not confirm whether you need a contractor’s license to build an entire Illinois house. Ask your city or county building office whether you can act as the general contractor at your proposed address. Describe the work you will do yourself. Ask separately about each trade you plan to hire. Before you buy land, ask for the local owner-builder application or affidavit, if the office uses one.

You can use Illinois’s homeowner plumbing exemption for a single-family home you are building to live in yourself¹. You can also qualify if you own or lease an existing single-family home and live there¹.

For a new Illinois home, you must intend to make the finished house your bona fide sole and exclusive residence¹. You must intend to live there for at least 6 months after construction ends¹. If you do not live there for that period, Illinois law presumes you lacked that intent; you can present evidence otherwise¹.

The Illinois exemption does not let you employ unlicensed plumbing helpers¹. Anyone you employ to help must hold a license under the Illinois Plumbing License Law¹. Ask IDPH's Plumbing Program how the occupancy condition applies to your plans.

You may still need a local plumbing permit even if you qualify for Illinois’s homeowner exemption³. Illinois lets cities, towns, villages, townships and counties require plumbing permits and charge fees³. Before issuing your permit, the local government must verify your plumbing license or qualifying owner-occupant status³.

Your work must meet the Illinois State Plumbing Code's minimum standards¹. Your plumbing is subject to inspection by IDPH or a local government with a licensed plumber as inspector¹. Ask your local plumbing permit office for its fee schedule and inspection stages. Ask what proof of ownership and occupancy you need to submit. Get those answers before you order materials or cover any plumbing.

Illinois has statewide baseline building-code requirements that took effect in 2025⁴. Whether your local government adopts a code is separate from its duties under the Illinois baseline⁵. A local government can choose not to adopt a building code and still have to meet applicable state baseline requirements⁵.

Locally adopted residential codes must meet the International Residential Code's minimum structural requirements⁴. Residential requirements differ where your local government has not adopted a code⁵. An agreement between the purchaser and builder to use an alternative code can also matter there⁵. Ask your local code official which code and edition apply to your owner-built house. If there is no local code official, ask the Capital Development Board about the residential baseline before you finish your plans.

Illinois has 20 counties without a residential building permit requirement in unincorporated areas². Another 23 Illinois counties have limited building permit requirements⁶. You need a residential building permit in 59 Illinois counties⁶. These county figures cover unincorporated land².

Brown County, Schuyler County and Crawford County do not require residential building permits². Richland County and Jefferson County require residential building permits⁶.

A county's building permit status does not establish an Illinois plumbing license exemption¹. Use the Illinois building permit comparison to narrow your search. Then ask the building office to confirm what you need for your address and proposed house.

Your local government handles any required building approval for a privately funded Illinois house⁴. Give your city or county building office the parcel address and a description of the work you plan to do. Ask for written answers about contractor qualifications, applications and fees. Ask who must sign each trade application.

Ask for the inspection schedule and what you must do before moving into the finished home. Illinois leaves any required occupancy permit for privately funded construction to local government⁴. Plan for the Illinois plumbing exemption’s occupancy condition too. For a new home, you must intend to live there for at least 6 months after construction¹. Ask IDPH's Plumbing Program to clear up any uncertainty before you do the plumbing yourself.