新加坡DfMA和PMEP简介（3/10）
2. GOOD INDUSTRY PRACTICES - PROCUREMENT
2. 良好的行业规范-采购
2.1. Early involvement of contractors and MEP specialists
2.1. 承包商和MEP专家的早期参与
It is important to engage the MEP specialists and main contractor early upfront during the design stage of the project. By incorporating their inputs into the design, a more effective technical solution can be achieved. Design clashes and structural safety concerns due to co-ordination issues can be eliminated. The design of MEP systems will also be more holistic and take into consideration the ease and accessibility of maintenance, replacement and upgrading of such systems.
重要的是，在项目的设计阶段，尽早聘请MEP专家和主承包商。通过将他们的输入整合到设计中，可以实现更有效的技术解决方案。由于协调问题而引起的设计冲突和结构安全问题可以消除。MEP系统的设计也将更加全面，并考虑该系统的维修、更换和升级的便利性和易用性。
The Design and Build (D&B) and Design Development and Build (DDB) procurement models facilitate early involvement of the main contractor and MEP specialists during the design stage. This significantly improves the buildability and constructability of the prefabricated MEP design, leading to higher construction productivity.
设计和建造(D&B)和设计开发和建造(DDB)采购模型促进了主承包商和MEP专家在设计阶段的早期参与。这大大提高了预制MEP设计的可建造性和可施工性，从而提高了施工生产率。
Design and Build (D&B) model
设计和建造(D&B)
D&B is a procurement method where the functions of design and construction are placed entirely with the main contractor. Based on the design brief provided by the client, the main contractor will engage his own consultants and the MEP specialists to fully design, develop and construct the development, including the design and installation of prefabricated MEP systems.
D&B是一种采购方法，设计和施工的功能完全由主承包商承担。根据业主提供的设计概要，主承包商将聘请自己的顾问和MEP专家全面设计、开发和施工开发，包括预制MEP系统的设计和安装。
Design Development and Build (DDB) model
设计开发和建造(DDB)
The DDB model is similar to the D&B model, except that the client will engage his own consultants to develop the conceptual design first. Based on this design concept, the main contractor will work with his own consultants and the MEP specialists to develop the full design and construct the development, including designing and installing the prefabricated MEP systems.
DDB模型与D&B模型相似，不同之处在于客户将先聘请自己的顾问来开发概念设计。基于这种设计理念，主承包商将与自己的顾问和MEP专家一起开发完整的设计并进行开发，包括设计和安装预制的MEP系统。
Besides the above procurement models, the consultants, main contractor and MEP specialists can also team up to submit their design to tender for projects.
除了上述采购模式外，顾问公司、总承包商和环保专家也可以合作提交设计以进行项目投标。
In the event when early contractor involvement cannot be adopted, the client can consider the following options:
如果不能采用早期承包商参与，客户可考虑以下选项:
Figure 3: Suggestions for a typical DBB project
图3:对典型DBB项目的建议
Below are examples of overseas procurement models and best practices from the United Kingdom, Japan and Korea.
以下是来自英国、日本和韩国的海外采购模式和最佳做法的例子。
2.2. Tender requirements and specifications
2.2. 招标要求及规格
The requirement to adopt prefabricated MEP modules cannot be an afterthought and needs to be incorporated upfront in the tender documents, starting from the project brief. The early decision to adopt MEP modules in the project allows greater continuity of design and maximises productivity gains.
采用预制件MEP模块的要求不能事后再考虑，需要从项目概要开始，在投标文件中预先纳入。在项目中采用MEP模块的早期决定允许更大的设计连续性和最大限度地提高生产率。
Project milestones are different when prefabricated MEP modules are adopted in a project. As such, the contract provisions of a project adopting prefabricated MEP modules should take into account the following considerations:
当一个项目采用预制的MEP模块时，项目里程碑是不同的。因此，采用预制MEP模块的项目合同条款应考虑以下因素:
2.2.1. Allow sufficient time to consider design options
2.2.1.留出足够的时间考虑设计选项
During planning, it is important to allocate sufficient time to consider a range of design options for prefabricated MEP modules with the help of BIM software, and avoid rushing into details which can limit the design options.
在规划过程中，重要的是要在BIM软件的帮助下，为预制的MEP模块分配足够的时间来考虑一系列的设计选项，避免匆忙进入细节，从而限制设计选项。
For example, a detailed design of a building’s services may pre-determine the construction sequence or limit the scope for preassembly. The use of a vertical riser in a frame passing through multiple floors may be more efficient than having a smaller assembly for each floor or fitting components in a traditional in-situ manner.
例如，建筑服务的详细设计可能预先决定建造顺序或限制预装的范围。在穿过多个楼层的框架中使用垂直立管可能比在每个楼层使用较小的组件或在传统的现场装配方式更有效。
However, lifting restrictions on the site may prevent this option from being used.
As various design options require inputs across the construction value chain, the client should allow adequate time for design in BIM software and collaboration among its consultants, builder, MEP trade specialists and prefabricator of MEP modules, before construction starts.
然而，取消对网站的限制可能会阻止使用此选项。
由于各种设计方案都需要在整个建筑价值链上进行输入，因此在施工开始前，客户应留出充足的时间进行BIM软件的设计，并与顾问、建造商、MEP贸易专家和MEP模块预制商进行协作。
2.2.2. Have Co-ordinated Services Drawings (CSD) endorsed by all relevant project parties Once prefabrication is completed, only minor changes are allowed. Any design changes or re-routing causes a lot of disruption.
2.2.2.在预制工程完成后，所有有关的工程承建商均通过统筹服务图则，只可作轻微更改。任何设计更改或重新路由都会导致大量中断。
Hence, it is important that the designs of the MEP services are confirmed early. Since all modules are manufactured based on BIM co-ordinated models, the process of approving the shop drawings is critical and must be robust.
因此，及早确认MEP服务的设计是很重要的。由于所有的模块都是基于BIM协调的模型制造的，所以施工图的审批过程非常关键，必须是稳健的。
The CSD needs to be endorsed by all relevant project parties i.e. the consultants, builder and relevant MEP trade specialists, according to a pre-agreed schedule.
Clients are also encouraged to require the main contractor and MEP specialists to provide more detailed BIM drawings to facilitate off-site prefabrication of MEP systems.
根据预先商定的时间表，政府发展计划必须得到所有有关项目各方，即顾问、建造商和相关环保部门专家的批准。
我们也鼓励客户要求主承包商和MEP专家提供更详细的BIM图纸，以促进MEP系统的场外预制。
2.2.3. Approve materials and mock-ups prior to mass production of MEP modules
2.2.3.在MEP模块量产前批准材料和模型
Unlike cast in-situ works where there is a sequence for materials to arrive on site, upfront material planning is critical for prefabricated MEP modules as all materials are needed at the same time for prefabrication.
与现场浇铸工程不同的是，材料到达现场是有顺序的，预先的材料计划对于预制的MEP模块是至关重要的，因为所有材料都需要在同一时间进行预制。
Consultants are required to approve the materials used early, so that prefabrication of modules can proceed on schedule. Mock-ups of the most typical prefabricated MEP modules used in the development should also be produced for the consultants’ approval, prior to mass production of the modules in the factory.
咨询人员需要尽早批准使用的材料，以便模块的预制可以按计划进行。开发中使用的最典型的预制MEP模块的模型也应该在工厂批量生产模块之前制作，以获得顾问的批准。
2.2.4. Ensure workers are trained and defects are rectified at the factory
2.2.4. 确保工人在工厂接受培训并纠正缺陷
The skills of the trade workers deployed at the factory play a critical role in ensuring the smooth installation of modules on site.
To avoid potential disputes, the tender can include requirements for MEP specialist contractors to provide training for workers in the factory, and to rectify defects found in the modules installed on site.
在工厂工作的贸易工人的技能对于确保模块在现场的顺利安装起着关键的作用。
为避免潜在的纠纷，投标可包括要求MEP专业承包商为工厂的工人提供培训，并纠正现场安装的模块中发现的缺陷。
To minimise defects in the modules due to poor workmanship, an engineer’s representative should be engaged by the consultant to inspect the works done in the factory. The engineer’s representative must be an independent party from the prefabricator to avoid conflict of interest.
为尽量减少因技术欠佳而造成的组件缺陷，顾问公司应聘请工程师代表检查工厂内的工程。工程师代表必须是与预制方独立的一方，以避免利益冲突。
2.2.5. Improve co-ordination on site and in the factory
2.2.5. 提高现场和工厂的协调能力
Clients can specify to engage firms under the CRS ME15 workhead as the first-level subcontractor to co-ordinate the installation of prefabricated MEP works. The firm should have a relevant track record in the co-ordination and installation of prefabricated MEP modules.
客户可以指定CRS ME15工作头下的公司作为一级分包商，协调预制MEP工程的安装。该公司应在预制MEP模块的协调和安装方面有相关的记录。
In addition, the tender should specify a dedicated firm or personnel to lead and direct the co-ordination among various trades on site and in the factory. The lead co-ordinator is preferably the builder that is well placed to co-ordinate logistics and activities of all trades on site.
此外，投标书应指定专门的公司或人员来领导和指导现场和工厂内各行业之间的协调工作。首席协调人最好是能在现场协调物流和所有行业活动的建筑商。
2.2.6. Adopt a different payment certification methodology
2.2.6. 采用不同的支付认证方法
With a different work sequence, the contractor’s pricing methodology will change and the consultants’ payment certification methodology and the bill of quantity, or schedule of works in the case of a lump sum contract will also have to be tailored accordingly. For example, if the MEP specialist contractor is also the prefabricator of MEP modules, the MEP specialist contractor can claim part of the contract amount for the modules completed in the factory, before the installation of these modules on site.
由于工作顺序不同，承包者的定价方法将会改变，顾问的付款证明方法和一次总付合同的工程量清单或工程时间表也必须相应调整。例如，如果MEP专业承包商同时也是MEP模块的预制商，那么在现场安装模块之前，MEP专业承包商可以对在工厂完成的模块提出部分合同金额的索赔。
The flowchart below shows a possible workflow to implement prefabricated MEP modules in a project. The next few chapters will explore the good practices for each phase of the flowchart.
下面的流程图显示了在项目中实现预制MEP模块的可能工作流程。接下来的几章将探讨流程图每个阶段的良好实践。