As of June 2012, The City Of Midlothian uses the following adopted codes:
- 2009 International Building Code and Amendments
- 2009 International Mechanical Code and Amendments
- 2009 International Plumbing Code and Amendments
- 2009 International Residential Code and Amendments
- 2009 International Energy Conservation Code and Amendments
- 2009 International Fuel and Gas Code and Amendments
- 2009 International Existing Building Code
- 2009 International Code Council Performance Code
- 2009 International Fire Code and Amendments
- 2011 National Electrical Code and Amendments