What Is MIA+BSI? Definition & Guide for Countertop Fabricators
MIA+BSI refers to the merger of the Marble Institute of America (MIA) and the Building Stone Institute (BSI), which combined in 2018 to form what is now known as the Natural Stone Institute. This organization is the leading authority on natural stone standards, education, and advocacy in North America. For countertop fabricators, the Natural Stone Institute (formerly MIA+BSI) provides the technical standards, accreditation programs, and industry resources that define professional-grade stone fabrication and installation.
TL;DR
- MIA+BSI merged in 2018 to become the Natural Stone Institute
- Sets the technical standards for natural stone fabrication and installation
- Publishes the Dimension Stone Design Manual, the industry's primary reference
- Offers fabricator accreditation through a rigorous shop inspection program
- Over 2,000 member companies across the supply chain
- Provides safety resources, especially for silicosis prevention
- Hosts education at TISE/StonExpo and through online programs
History: From MIA and BSI to the Natural Stone Institute
Marble Institute of America (MIA)
Founded in 1944, MIA was the primary organization serving the dimensional stone industry. It set standards for stone fabrication, published care and maintenance guides, and provided education for fabricators, architects, and designers. MIA's standards became the reference point for quality in natural stone work.
Building Stone Institute (BSI)
Founded in 1919, BSI focused on the quarrying, manufacturing, and use of natural stone in commercial and residential construction. Its membership included quarries, fabricators, and installers working primarily on exterior and structural stone applications.
The 2018 Merger
In 2018, MIA and BSI merged to form the Natural Stone Institute, creating a single organization that covers the entire natural stone supply chain from quarry to finished installation. The combined organization has over 2,000 member companies and is headquartered in Oberlin, Ohio.
What the Natural Stone Institute Does for Fabricators
Technical Standards
The Natural Stone Institute publishes and maintains the standards that govern natural stone work in North America:
| Publication | Content | Fabricator Relevance |
|---|---|---|
| Dimension Stone Design Manual | Material specs, tolerances, installation standards | Primary technical reference |
| Stone Fabrication Guidelines | Cutting, polishing, seaming, edge work | Day-to-day fabrication standards |
| Installation Standards | Setting, leveling, support, seaming in the field | Install crew training reference |
| Care & Maintenance Guides | Sealing, cleaning, stain removal | Customer handout material |
| Safety Standards | Silica dust, material handling, equipment safety | OSHA compliance reference |
These standards are frequently referenced in architectural specifications for commercial projects. A fabrication shop that follows Natural Stone Institute standards can demonstrate compliance when bidding on projects that require adherence to published industry standards.
Accreditation Program
The Natural Stone Institute offers a fabricator accreditation program that involves:
- Application and documentation of shop procedures, safety protocols, and quality control measures
- On-site inspection by a trained evaluator who examines equipment, processes, finished work, and safety compliance
- Review and approval by an accreditation committee
- Annual renewal with ongoing compliance requirements
Accredited fabricators can display the Natural Stone Institute accreditation mark, which carries weight with:
- Architects and designers specifying commercial stone work
- General contractors evaluating subcontractor qualifications
- Material suppliers selecting preferred fabrication partners
- Homeowners researching fabricators for high-end residential projects
As of recent data, approximately 200-300 fabrication shops across the US hold Natural Stone Institute accreditation - a small fraction of the estimated 8,000-10,000 active fabrication shops.
Education and Training
The Natural Stone Institute provides education through multiple channels:
- Online courses covering stone identification, fabrication techniques, and installation best practices
- In-person workshops at TISE/StonExpo and regional events
- Webinars on trending topics like silicosis safety, new materials, and business management
- Study programs for employees at all levels, from new hires to experienced fabricators
Safety Advocacy
The organization has been at the forefront of silicosis awareness and prevention in the stone industry. Resources include:
- Detailed guides for OSHA Table 1 silica dust compliance
- Best practices for wet cutting, dust collection, and respiratory protection
- Sample written exposure control plans
- Training materials for worker education
Natural Stone Institute Membership
| Member Category | Annual Dues Range | Includes |
|---|---|---|
| Fabricator (small) | $500-$800 | Standards access, education, directory listing |
| Fabricator (mid/large) | $800-$2,000+ | All above + committee participation |
| Quarry/manufacturer | $1,000-$5,000+ | Industry representation and advocacy |
| Supplier/vendor | $800-$3,000+ | Marketplace visibility |
ROI of Membership
For a fabrication shop, the return on membership comes through:
- Commercial project access: Many specs require Natural Stone Institute member or accredited fabricators
- Technical support: Direct access to standards experts when questions arise on complex projects
- Marketing credibility: The accreditation mark on your website and business cards signals quality
- Error prevention: Following published standards reduces remake rates
Natural Stone Institute vs. Other Organizations
| Organization | Focus | Stone Fabricator Value |
|---|---|---|
| Natural Stone Institute (MIA+BSI) | Natural stone (quarry to install) | Very high - core standards body |
| ISFA | All surface materials | High - broader material coverage |
| NKBA | Kitchen and bath design | Medium - designer connections |
| SFA (Stone Fabricators Alliance) | Business coaching for fabricators | High - peer group learning |
Many fabrication shops maintain membership in multiple organizations, choosing based on their material mix, project types, and business development priorities.
Key Publications Every Fabricator Should Know
Dimension Stone Design Manual
This is the definitive technical reference for natural stone. It covers:
- Physical properties of stone types (density, absorption, flexural strength)
- Design tables for overhang limits, support spacing, and thickness requirements
- Seam standards and acceptable tolerances
- Installation methods for various applications
Fabrication and Installation Standards
These documents specify acceptable tolerances for:
- Edge profile consistency: +/- 1/32"
- Surface flatness: within 1/16" per 10 feet
- Seam height differential: within 1/64" for polished surfaces
- Overhang consistency: within 1/8" along the run
Knowing these numbers protects your shop when customers or contractors claim work is substandard.
FAQ
What does MIA+BSI stand for?
Marble Institute of America + Building Stone Institute. They merged in 2018 to form the Natural Stone Institute.
Is MIA+BSI still called that?
The official name is now the Natural Stone Institute. "MIA+BSI" is sometimes used informally, and the individual histories of MIA and BSI remain part of the organization's identity.
How do I become an accredited fabricator?
Apply through the Natural Stone Institute website, prepare your documentation, and schedule an on-site inspection. The process typically takes 2-4 months.
How much does accreditation cost?
Accreditation fees vary based on shop size but typically run $1,500-$3,000 including the inspection. Annual renewal is less.
Is Natural Stone Institute membership required to work with natural stone?
No. Membership is voluntary. However, accreditation and membership provide competitive advantages, especially for commercial projects.
What is the Dimension Stone Design Manual?
It is the primary technical reference for natural stone in North America, covering material properties, design specifications, fabrication standards, and installation methods.
Does the Natural Stone Institute cover quartz and engineered stone?
The organization's primary focus is natural stone. Quartz and other engineered materials are more directly served by ISFA and individual manufacturer programs.
How does Natural Stone Institute accreditation help win bids?
Many commercial project specifications require fabricators to be Natural Stone Institute members or accredited. Without it, you may not even be eligible to bid.
Can I access Natural Stone Institute standards without being a member?
Some resources are available to non-members, but the full standards library, design manual, and technical support require membership.
Does the Natural Stone Institute help with silicosis compliance?
Yes. The organization provides detailed OSHA compliance guides, sample written plans, and training resources specifically for silica dust management in stone fabrication shops.
Run Your Shop to Industry Standards
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Sources
- Natural Stone Institute - Official Website
- Marble Institute of America - Historical Archives
- Building Stone Institute - Historical Archives
- Natural Stone Institute - Accreditation Program Documentation
- Stone World Magazine - MIA+BSI Merger Coverage
- Natural Stone Institute - Dimension Stone Design Manual