Basement ADUs & In-Law Suites in St. Charles, MO

 Whether for multi-generational living, long-term guests, or additional income potential, a well-designed basement ADU adds both comfort and lasting value to your home. 

An Accessory Dwelling Unit (ADU) is a fully functional living space within or attached to your home. In a basement setting, it typically includes:

• A bedroom and living area 
• A bathroom or powder room 
• A kitchenette or full kitchen 
• A private entrance or egress window 

Basement ADUs are ideal for homeowners who want to make better use of existing square footage without expanding outward.

Before starting your basement conversion, it’s important to meet local building codes and safety regulations. In St. Charles, Missouri:

• A permit is required to finish or convert a basement into a dwelling unit. 
• The apartment must meet building and safety codes, including: 
  • Minimum ceiling height (typically at least 7 feet) 
  • Proper insulation and HVAC for year-round comfort 
  • At least one emergency egress window or exterior door 
  • Electrical, plumbing, and fire safety compliance 
• The design must be approved through the City of St. Charles permit review process before construction begins.
   

💡 Our team handles all permitting and code compliance so your project is smooth, safe, and fully legal.

When designing an in-law suite or basement apartment, balance comfort, accessibility, and style.

Popular Features Include:

• Open-concept layouts to maximize space 
• Separate entryways for privacy 
• Luxury vinyl plank flooring for durability and warmth 
• Full-size or compact kitchens 
• Bright LED lighting and large egress windows for natural light 
• Universal design elements for accessibility 

Our design team specializes in custom ADU layouts that feel connected to your home yet offer full independence for guests or relatives.