Transparent contracts and costs



We flexibly incorporate various contracting methods to provide the best contract suited to client needs (cost and construction Schedule).

Lump-sum Method

  • This is a contracting method in which Obayashi undertakes construction work as set total price.
  • The majority of the contracting methods currently used for construction work in Japan is, lump-sum method.
  • In the lump-sum method, the total construction cost is calculated after the design work is completed, then the contract would be finalized.
  • Client has the advantage of knowing the estimated cost of the entire project from the initial stages.
Lamp-sum Method

Open book method

  • This method is disclosing client the process of selecting specialty construction companies, the cost of ordered amount to vendor and selected construction companies.
  • It requires manpower to support the selection of a specialty construction company and a time frame for the selection process.
  • It has the advantage of cost transparency for the client.
  • The construction cost in the open book method is based on the concept of "Cost + Fee".
  • A Guaranteed Maximum Price (GMP), which is the maximum target for the total construction cost, would be set in advance.
Open book method

Cost-on method

  • This method is used when the client designates a specialty construction company (cost-on company), such as for equipment installation.
  • Obayashi will sign a subcontract with the specialty construction company after the cost agreement between the client and the specialty construction company.
  • Further, Obayashi sign a contract with the client for the above cost plus our cost-on-fee, including our general management costs.
Cost-on method

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Advanced procurement of long lead-time items

Due to the increasing demand for Data Center constructions around the world, the delivery of equipment and facilities required for Data Centers tends to take longer than usual in the past. Obayashi will work closely with the client to meet the delivery date to the client through design, procurement and construction capabilities.

  • In order to shorten construction duration, procurement work for long lead-time items will be launched at the detail design stage.
  • In conjunction with the design process, select vendors, prepare production guidelines, contract and place orders.
  • Early procurement implementation ensures an overall schedule with no time loss.
Advanced procurement of long lead-time items

Overseas Procurement

Overseas procurement contracting schemes include both Whole set contracts (materials and workers arranged with whole set) and Separate contracts.
Propose the most appropriate procurement scheme according to the client's requirements and procurement items.

  • Whole set contracts

    Whole set contracts

    Whole set of materials and workers will be contracted through a domestic subcontractor.

  • Separate contracts 1

    Separate contracts 1

    Contracting separate of materials and workers, materials will be contracted through distributor or trading company.

  • Separate contracts 2

    Separate contracts 2

    Contracting separate of materials(*1) and workers, materials will be contracted directly with overseas subcontractors (manufacturers)(*2).

*1 In some cases of Separate contracts, the contract for materials may be procured directly by the client.
(In such cases, materials will be treated as supplied.)

*2 Overseas subcontractors include Overseas manufacturers

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