2026 Interiors Square Foot Costbook

Printed book PLUS A FULL ONE-YEAR SUBSCRIPTION to BNi ACCESS™ Square Foot ✓

We're excited to announce a new partnership between BNi and eConverge, combining the trusted BNi Costbook data with eConverge’s leading software. This powerful integration transforms the Costbook into a streamlined online estimating tool - saving time, reducing errors, and boosting efficiency.

Here is a quick tour video of BNi ACCESS™ Square Foot:

Create Interior Construction Estimates with Confidence with the 2026 Interiors Square Foot Costbook

Interior construction can account for 40 - 60% of total building costs - and it’s also one of the most complex aspects to estimate. That’s why the Interiors Square Foot Costbook 2026 Edition is an essential resource for every construction and design professional. This book compiles 65 real-world case studies, meticulously broken down to show square foot costs by interior component across various building types - commercial, educational, civic, residential, healthcare, and more.

Each case study includes detailed project descriptions, contextual insights, and cost breakdowns by MasterFormat® division. This year’s edition also features an updated unit-in-place section covering thousands of individual materials and components, as well as city-based cost modifiers so you can tailor estimates to your geographic region.

Option #1: Order Premium Edition

Order the 2026 Interiors Square Foot Costbook and start estimating immediately with your BNi ACCESS™ Square Foot account. Work from anywhere, explore costs by project type, roof, or wall system, apply regional modifiers for precise local pricing, and easily share estimates as PDFs.

Premium Edition Includes: 

• • Printed book
  • BNi ACCESS™ Square Foot powered by eConverge™ for one full year
  • Includes access to over 1,400 cost models
  • Includes unit-in-place and assembly costs for refinement
  • Adjust project costs by location with 600+ Metro Area Multipliers 
  • Designed to reflect the challenges of working around existing conditions
  • Covers public, educational, healthcare, housing, and commercial projects

Option #2: Order Book Only

Get all the information you need in a fully-indexed printed book format. Perfect for those who prefer the reliability and feel of a physical book for learning or reference.

Please note that by ordering this 2026 edition, you will automatically receive a copy of the 2027 edition for a no-obligation 30-day trial, as soon as it is released.  This is to ensure you are always working with the latest available data.  You can opt-out of this auto-renew program at any time.

Disclaimer: BNi ACCESS™ Square Foot is designed for general estimating and project planning purposes. It is not intended for use with Job Order Contracting (JOC) and should not be used for JOC- specific pricing, procurement, or contractual decisions.