What is iTWO Cost Estimation?
iTWO (formerly ARRIBA) is the leading construction cost estimation software by RIB Software SE and the industry standard for bid calculation in public construction tenders in Germany.
Functionality
| Module | Function | Procurement relevance |
|---|---|---|
| iTWO Calculation | Bid estimation | Unit prices for tenders |
| iTWO Measurement | Quantity surveying | Billing basis |
| iTWO Billing | Final invoice | Contract execution |
| iTWO 5D BIM | Building Information Modeling | Large projects |
Calculation Method (Surcharge Calculation)
- Direct costs: Labor, materials, equipment, subcontractors
- Site overheads (BGK): Site setup, on-site management
- General overheads (AGK): Administration (typically 8-15%)
- Risk and profit (W+G): Typically 3-8%
GAEB Integration
iTWO is seamlessly integrated with GAEB data exchange:
- DA83: Import bill of quantities from tender
- DA84: Export bid submission
- DA85: Import contract award
- DA86: Quantity measurement
- DA89: Invoicing
Market Position
iTWO/ARRIBA holds approximately 60% market share in Germany, followed by California.pro (~15%), BRZ (~10%), and others.
Patterno Helps
Patterno-BID for construction offers a native iTWO integration. Our AI calculation agent imports the GAEB bill of quantities, automatically estimates positions based on your master data, and generates the GAEB DA84 export in seconds – a 10x time saving compared to manual calculation.