Installation Providers

The installation contractor providers on this provider network span the full spectrum of US construction trades — from structural and civil work through mechanical, electrical, and specialty finish systems. Each entry is drawn from publicly available licensing data, trade registration records, and contractor classification frameworks aligned to Construction Specifications Institute (CSI) MasterFormat divisions. The scope covers commercial, residential, and industrial installation contractors operating at the national level, organized to support service seekers, procurement teams, and researchers navigating a complex and heavily regulated sector.

How providers are organized

Providers are structured according to the 16-division MasterFormat taxonomy published by the Construction Specifications Institute (CSI), which assigns every construction trade and installation type to a standardized division code. This classification system governs how entries are grouped, labeled, and filtered within the network.

Primary organization follows 3 broad functional bands:

1. Structural and civil installations — Divisions 01 through 14, covering concrete, masonry, metals, wood and plastics, thermal and moisture protection, openings, and conveying equipment.
2. Mechanical, electrical, and plumbing (MEP) installations — Divisions 20 through 28, covering fire suppression, plumbing, HVAC, electrical, communications, and electronic safety and security systems.
3. Specialty and finish installations — Divisions 30 through 48, covering earthwork, exterior improvements, utilities, and electrical power generation.

Within each division, providers are further segmented by contractor license class, where applicable. Licensing classifications vary by state — California's Contractors State License Board (CSLB), for example, recognizes over 40 specialty license classifications (C-class) distinct from the general B-class license, while Texas licenses through the Department of Licensing and Regulation (TDLR) with a different classification structure. Entries reflect the licensing jurisdiction in which the contractor holds active registration, not simply the state where work is performed.

For a broader understanding of how this provider network fits within the construction installation reference landscape, see the page.

What each provider covers

Each provider network entry contains a structured set of fields drawn from verifiable public records and trade registration sources. The following fields appear across all providers:

1. Contractor name and legal entity type — LLC, corporation, sole proprietor, or partnership, as recorded with the relevant state licensing board.
2. Primary trade division — CSI MasterFormat division code and description.
3. License class and number — Issued by the applicable state licensing authority; entries without active licensure are flagged as unverified.
4. Geographic service area — State or multi-state coverage, drawn from licensing jurisdiction records.
5. Permit and inspection alignment — Whether the contractor's scope typically triggers building permits, mechanical permits, electrical permits, or specialty permits under the International Building Code (IBC) or applicable state amendments.
6. Relevant code references — Named codes applicable to the installation type, including the IBC, International Mechanical Code (IMC), National Electrical Code (NFPA 70), and International Plumbing Code (IPC).
7. Safety classification — OSHA regulatory category applicable to the trade, primarily drawn from 29 CFR 1926 (Construction Safety Standards), which governs fall protection, scaffolding, electrical work, and excavation, among other hazard categories.

Providers for electrical contractors additionally reference National Electrical Contractors Association (NECA) standards where applicable, and HVAC entries note whether the contractor holds EPA Section 608 certification, which is federally required for handling refrigerants.

Comparing two representative provider types illustrates the range: a concrete flatwork contractor (Division 03) carries a general contractor or concrete specialty license, references ACI 301 specification standards, and triggers foundation or slab permits under IBC Chapter 19 — while a low-voltage communications installer (Division 27) typically holds a limited energy or data/voice/video license, references BICSI cabling standards, and may be permit-exempt in jurisdictions that carve out low-voltage work from building permit requirements.

For full guidance on interpreting and using these entries, see How to Use This Installation Resource.

Geographic distribution

The provider network covers all 50 US states, with provider density reflecting the distribution of licensed contractor registrations across state databases. The 5 states with the highest contractor licensing volume — California, Florida, Texas, New York, and Pennsylvania — account for a disproportionate share of entries, consistent with their share of total US construction spending.

Geographic coverage is organized at 3 levels:

• State-licensed entries — Contractors holding licensure in a single state, operating within that jurisdiction's code and permit framework.
• Multi-state entries — Contractors registered in 2 or more states, often through reciprocity agreements or independent multi-jurisdiction licensing.
• Federal project specialists — Contractors whose primary scope involves federally funded construction subject to Davis-Bacon Act prevailing wage requirements and federal agency inspection protocols, rather than municipal permit workflows.

States without statewide contractor licensing mandates — including Colorado, which relies on local jurisdiction licensing — are noted within relevant entries to flag that verification must occur at the county or municipality level rather than a central state registry.

How to read an entry

Each provider page follows a fixed structure. The top block displays the contractor's legal name, primary CSI division, and license status. A status indicator — Active, Inactive, or Unverified — reflects the last confirmed check against the issuing state board's public database.

Below the identification block, the permit and code reference field names the specific permit type the contractor's work triggers and the governing code section. An HVAC mechanical contractor entry, for example, will reference International Mechanical Code (IMC) Section 301 for equipment installation and note that mechanical permits are required prior to rough-in inspection in most jurisdictions adopting the IMC.

The safety classification field references the applicable OSHA subpart under 29 CFR 1926. A roofing installer entry will cite Subpart M (Fall Protection), while an excavation contractor entry will cite Subpart P (Excavations). These references do not constitute compliance guidance — they identify the regulatory category applicable to the trade for research and verification purposes.

Entries that include a specialty certification field — such as EPA 608 for refrigerant handling or NABCEP certification for photovoltaic installers — note the issuing body and, where publicly searchable, the certification lookup URL. The full provider network structure and its relationship to trade classification are detailed on the Installation Providers index.