Reference edition, published since 2026 Updated . Questions: contact the editors.

Interior Design U.S.

Residential planning standards, codes and costs

All articles

Every article published by Interior Design U.S.: reference articles on room dimensions, kitchen and bath planning, accessibility, lighting, costs, and contracts.

Room Planning

Minimum room sizes, ceiling heights, hallways, stairs, and the NKBA kitchen and bath clearances that make a floor plan work. The articles are listed below with the publication date and a one-sentence summary of each.

  • NKBA Kitchen and Bath Planning Guidelines

    The NKBA kitchen and bathroom planning guidelines in numbers: work aisles, work triangle, landing areas, storage frontage, fixture clearances, and grab bars.

  • Residential Room Dimension Standards (IRC)

    Minimum room area, ceiling height, hallway, stair, door, and egress window dimensions from the 2021 IRC, plus the clearances NKBA and ICC A117.1 add above code.

  • WaterSense bathroom water worksheet

    Compare showerhead and bathroom faucet water use with EPA WaterSense flow limits, stated household assumptions, worked gallon totals and a downloadable worksheet.

Codes and Standards

Accessibility clearances from the 2010 ADA Standards and ICC A117.1, and residential lighting levels from the IES, with the numbers behind each rule. The articles are listed below with the publication date and a one-sentence summary of each.

  • ADA and ICC A117.1 Accessibility Clearances

    Clear floor space, turning space, door widths, reach ranges, and toilet, shower, and kitchen clearances from the 2010 ADA Standards and ICC A117.1-2017.

  • Residential Lighting Levels in Footcandles

    IES-based footcandle ranges by room, the lumen math for typical room sizes, bulb equivalents, Kelvin and CRI, and the 1 footcandle stair rule in the IRC.

Costs and Contracts

Trade wages by state from the BLS, remodel job costs by region from Cost vs. Value, and the clauses a residential design agreement must contain. The articles are listed below with the publication date and a one-sentence summary of each.

  • How to Read an Interior Design Contract

    What a residential interior design contract contains: ASID package schedules, hourly, flat, percentage, and cost-plus fees, retainers, markups, and 16 CFR 429.

  • Interior Labor and Remodel Costs by Region

    May 2025 BLS wages for painters, carpenters, electricians, plumbers, and tile setters by state, 2025 Cost vs. Value remodel costs by region, NAHB finish costs.