HS2 Ltd explained that it had not expected to have an estimate of costs that it was confident in until the end of 2022 following work by the construction partner on a detailed, ‘bottom-up’ costing of the design.55 This followed the two-stage procurement process that HS2 Ltd told us it is employing on the HS2 programme, where the construction partner is first appointed based on capability and suitability and then works with HS2 Ltd to develop a design and agree a target price for construction....

HS2 Ltd explained that it had not expected to have an estimate of costs that it was confident in until the end of 2022 following work by the construction partner on a detailed, ‘bottom-up’ costing of the design.55 This followed the two-stage procurement process that HS2 Ltd told us it is employing on the HS2 programme, where the construction partner is first appointed based on capability and suitability and then works with HS2 Ltd to develop a design and agree a target price for construction.56 The Department confirmed that this is a standard approach for large construction projects where there is significant unknown risk and where more desig Type: conclusion | Number: 22 | Response status: accepted Government response: 5.1 The government agrees with the Committee’s recommendation. Target implementation date: December 2023 5.2 The HS2 Parliamentary report published in October 2022 set out HS2 Ltd.’s assessment of a £0.4 billion pressure for Euston station above its £2.6 billion budge