ERP for Construction Companies — software for Bauunternehmen under VOB and GAEB
Construction companies (Bauunternehmen) in the German Bauhauptgewerbe (primary construction trade) operate on long-running projects, with rigid commercial rules (VOB — Vergabe- und Vertragsordnung für Bauleistungen), standardised data formats (GAEB — the German construction-data-exchange standard), heavy subcontractor flows and significant equipment-fleet capital. An ERP for Bauunternehmen has to handle VOB-conformant project accounting, GAEB import and export, subcontractor-payment workflows, site cost tracking, fleet management and the BIM (Building Information Modelling) layer that customers increasingly mandate.
Requirements for construction-company ERP
The functional backbone is a VOB-conformant project ledger. Each construction project carries a tender (Angebot), a contract (Auftrag), interim invoices (Abschlagsrechnungen), a final invoice (Schlussrechnung) and a retention (Sicherheitseinbehalt). The ERP must track all of these with the right tax handling (§ 13b reverse charge for construction services), the right cost-allocation logic per Leistungsverzeichnis position and the right approval workflow. Subcontractor management adds another layer: VOB/B engages subcontractors under their own contracts and the ERP must coordinate the chain of progress acknowledgements, retention releases and warranty timelines. Equipment-fleet management (excavators, formwork, scaffolding) needs a separate cost-allocation logic distinct from materials and labour.
Mandatory functions
Mandatory functions include: VOB-conformant project ledger with interim and final-invoice workflow, retention handling and warranty-period tracking; GAEB 90, 2000 and DA-XML exchange formats (X81/X83/X84/X86 messages) for tender exchange with public and private clients; subcontractor-payment workflow with § 13b handling; equipment-fleet management with internal billing rates and utilisation tracking; site cost tracking with daily-report (Bautagebuch) capture on mobile; BIM/IFC integration at the project-information level so that 5D quantities can flow into the cost model; and Bauhauptgewerbe-conformant payroll (SOKA-Bau contributions, BG-BAU classifications). Audit-trail coverage matters for tax audits and for client audits on cost-plus projects.
Vendor landscape
The German construction-software market has clear specialists. BRZ.Software and Nemetschek-Bausoftware (with iTWO and other brands) dominate the mid-market and upper segment. RIB iTWO is the reference for 5D BIM-driven construction management on large projects. BauSU and ConWize cover the SMB and mid-market range with strong VOB and GAEB fidelity. For smaller Bauunternehmen up to ~50 employees, Handwerk-oriented vendors (Streit V.1, pds Software) extend into building construction with mixed depth. Generic Mid-Market ERPs rarely succeed in the Bauhauptgewerbe without a heavy construction add-on, because VOB and GAEB are non-trivial to retrofit.
Trends and outlook
Three trends are shaping construction-company ERP decisions. First, BIM is moving from a public-sector procurement preference to a private-sector expectation, and ERPs that ingest IFC quantities and link them to the cost model gain a real edge. Second, the e-Rechnung mandate (B2G XRechnung is already required, B2B from 2026) is pushing GAEB-based bidding and structured invoicing into the same back-office workflow. Third, materials volatility — steel, concrete, insulation — pushes Bauunternehmen to rebid more frequently, raising the value of GAEB-import speed and accuracy.
Related Topics
Frequently Asked Questions
Why is GAEB import/export so important?
Because GAEB is the standard data format for construction tenders in Germany. Clients send tender documents in GAEB DA-XML (X81/X83); bidders return them as priced offers (X84/X86). An ERP without robust GAEB support forces the back office to retype line items, which both wastes time and introduces calculation errors that can damage margin on hundreds of positions.
Can a generic ERP handle VOB project accounting?
Only with a construction-specific add-on and significant tailoring. The Abschlagsrechnung / Schlussrechnung pattern, retention handling, § 13b reverse-charge logic and the per-position cost allocation against a Leistungsverzeichnis are non-trivial to retrofit. Most construction firms either pick a specialist construction ERP from the start or accept a high customisation bill on a generic platform.
How relevant is BIM/IFC integration for SMB construction companies?
It depends on the customer mix. Large clients (public sector, real-estate developers, industrial buyers) increasingly require BIM-based delivery. SMB Bauunternehmen working mostly on smaller private and residential projects can defer the BIM investment, but should at minimum select an ERP that has an IFC ingestion roadmap, because retrofitting BIM later is significantly more expensive than choosing for it up front.