Contractor’s proposals (CP) in AEC industry refer to documentation prepared by tenderers for design and build projects or on a traditional contract where the bidder is to design specific parts of the works in response to employers’ requirements.
The Employer’s Requirements (ER’s) are often referred to as Employer Information Requirements (EIR) referencing the superseded PAS 1192 specification.
In ISO 19650 framework, the employer requirements are referred to as Exchange Information Requirements (EIR) a term which describes a broad group of requirements which can include all or a few of the following documents:
- Architectural Specification
- Structural Specification
- Civil Specification
- Environmental Specification
- MEP Specification
- BREEAM Requirements
- Scope of Services
- Allocation of Risk
- Design drawings or a building information model
- Method statements
- A BIM Execution Plan (BEP) if building information modelling is being used
- A programme (Schedule)
- An initial construction phase plan.
The contractor’s proposals information should establish the bidding organisation’s proposals for designing and constructing the project’s relevant parts, in conjunction with the price.
The format and content of CP should be as described in the EIRs and be written in response to the EIR; the CP might include the items included in EIRs, and:
- The tender price and contract sum analysis
- Scope gaps between the contractor’s proposals and the employer’s requirements.
- Any proposed provisional sums.
- Proposed sub-contractors
- Details of insurances.
- CV of staff along with a summary of their relevant experience on similar projects.
- Schedule of derogations
Once the contractor has received the proposal, there will be a negotiation phase. Any deviations between the contractor and the employer’s requirements will be discussed and amended to ensure agreement.
This is a crucial part of the tendering process, as it is not always clear which document will prevail after the contract is concluded. The CP may not meet all employer’s requirements/exchange information requirements, scope gaps, and derogations should be highlighted. The basis of technical solutions and additional information shall clarify what is included in the tender. 
 Designing Buildings Wiki, 2020. Contractor’s proposals for building design and construction – Designing Buildings Wiki [WWW Document]. Designing Buildings Wiki. (accessed 1.25.21).