Tender

WP1140 - T5D Design Consultant

COSTAIN LIMITED (H7-HEATHROW)

This public procurement record has 1 release in its history.

Tender

02 Jun 2026 at 09:20

Tender Notice
Summary of the contracting process

The procurement process, initiated by Costain Limited (H7-Heathrow), involves the provision of engineering design services for the WP1140 - T5D Design Consultant project, located in London, United Kingdom. This tender falls under the “Engineering design services” industry category with a CPV code of 71320000. The objective of the project is to replace the four attenuators in the T5D Shaft at Heathrow Rail Tunnels to enhance safety and reduce maintenance needs. The tender is currently at the Tender stage with a submission deadline of 9th June 2026. The project is valued between £2,500,000 and £5,000,000, with the contract period expected to run from 7th August 2026 to 1st December 2026. The procurement process is suitable for SMEs and VCSEs, providing a significant opportunity for growth in this sector.

This tender presents valuable opportunities for businesses specialising in underground rail network ventilation resilience, particularly those with expertise in airflow modelling and compliance with operational rail network constraints. With the requirement for a Ventilation Resilience Report, it supports businesses that have capabilities in engineering design services and an understanding of complex mechanical, electrical, and plumbing (MEP) systems. Additionally, firms with experience in executing projects in busy urban environments like London, especially within the constraints of operational rail networks, would find this tender especially appealing, potentially leading to long-term partnerships and increased market presence.

Find more tenders on our Open Data Platform.
How relevant is this notice?

Notice Information

Notice Title

WP1140 - T5D Design Consultant

Notice Description

The T5D Rail-tunnel Ventilation Shaft is located adjacent to T5D at its North and can be accessed from the bottom (Level 6) via the trackside of the HEX tunnel or from the top (level 7) via Airside. The objective is to replace the four attenuators in the T5D Shaft because they are at their end of life. The renewal of the T5D attenuators aims to reduce the risk of debris entering fans, tunnels and station, prevent the fans from failing in any fire scenario and provide ventilation and smoke clearance for the Heathrow Rail Tunnels. This improves safety conditions within Heathrow Rail Tunnels and improves resilience of systems. In addition, less maintenance and repair are required for the attenuator. Each attenuator is formed of four quadrants weighing around 1160 kg. Review MEP systems along the airflow and advise replacement/modification to bring them up to compliance. Surveys will be carried out by others (Employed by the Client) under the direction of the Design Consultant Item Question Q1 Do you have experience with Underground rail network ventilation resilience? Requirement: Ventilation Resilience Report required for the HAL Rail underground network. Q2 What capability do you have of air flow modeling for fans / attenuators etc.? Requirement: Model the existing configuration with one fan operating, and both fans operating and then repeat the modelling with shaft sub divided to allow one set of attenuators to be replaced while the other is operational. Q3 What capability do you have of understanding the requirements for specifying replacement attenuators etc., Specifically considering the constraints of an operational rail network? Note: - RIBA 5 onwards including construction is excluded.

Notice Details

Publication & Lifecycle

Open Contracting ID
ocds-b5fd17-abb75190-6054-4f95-b2a7-26ec9ecfbe8d
Publication Source
Contracts Finder
Latest Notice
https://www.contractsfinder.service.gov.uk/Notice/2a1ded63-c1d7-4984-9540-4dd819838020
Current Stage
Tender
All Stages
Tender

Procurement Classification

Notice Type
Tender Notice
Procurement Type
Standard
Procurement Category
Services
Procurement Method
Not Specified
Procurement Method Details
Tender Suitability
SME, VCSE
Awardee Scale
Not specified

Common Procurement Vocabulary (CPV)

CPV Divisions

71 - Architectural, construction, engineering and inspection services

CPV Codes

71320000 - Engineering design services

Notice Value(s)

Tender Value
£5,000,000 £1M-£10M
Lots Value
Not specified
Awards Value
Not specified
Contracts Value
Not specified

Notice Dates

Publication Date
2 Jun 20261 weeks ago
Submission Deadline
9 Jun 2026Expired
Future Notice Date
Not specified
Award Date
Not specified
Contract Period
6 Aug 2026 - 1 Dec 2026 1-6 months
Recurrence
Not specified

Notice Status

Tender Status
Active
Lots Status
Not Specified
Awards Status
Not Specified
Contracts Status
Not Specified

Buyer & Supplier

Contracting Authority (Buyer)

Main Buyer
COSTAIN LIMITED (H7-HEATHROW)
Contact Name
Available with D3 Tenders Premium →
Contact Email
Available with D3 Tenders Premium →
Contact Phone
Available with D3 Tenders Premium →

Buyer Location

Locality
MAIDENHEAD
Postcode
SL6 4UB
Post Town
Slough
Country
England
Major Region (ITL 1)
TLJ South East (England)
Basic Region (ITL 2)
TLJ1 Berkshire, Buckinghamshire and Oxfordshire
Small Region (ITL 3)
TLJ15 Berkshire East
Delivery Location
TLI London
Local Authority
Windsor and Maidenhead
Electoral Ward
Oldfield
Westminster Constituency
Maidenhead

Further Information

Notice Documents

Open Contracting Data Standard (OCDS)

View full OCDS Record for this contracting process

Download

The Open Contracting Data Standard (OCDS) is a framework designed to increase transparency and access to public procurement data in the public sector. It is widely used by governments and organisations worldwide to report on procurement processes and contracts. 

{
    "tag": [
        "compiled"
    ],
    "id": "ocds-b5fd17-abb75190-6054-4f95-b2a7-26ec9ecfbe8d-2026-06-02T10:20:04+01:00",
    "date": "2026-06-02T10:20:04+01:00",
    "ocid": "ocds-b5fd17-abb75190-6054-4f95-b2a7-26ec9ecfbe8d",
    "language": "en",
    "initiationType": "tender",
    "tender": {
        "id": "C4N113536273",
        "title": "WP1140 - T5D Design Consultant",
        "description": "The T5D Rail-tunnel Ventilation Shaft is located adjacent to T5D at its North and can be accessed from the bottom (Level 6) via the trackside of the HEX tunnel or from the top (level 7) via Airside. The objective is to replace the four attenuators in the T5D Shaft because they are at their end of life. The renewal of the T5D attenuators aims to reduce the risk of debris entering fans, tunnels and station, prevent the fans from failing in any fire scenario and provide ventilation and smoke clearance for the Heathrow Rail Tunnels. This improves safety conditions within Heathrow Rail Tunnels and improves resilience of systems. In addition, less maintenance and repair are required for the attenuator. Each attenuator is formed of four quadrants weighing around 1160 kg. Review MEP systems along the airflow and advise replacement/modification to bring them up to compliance. Surveys will be carried out by others (Employed by the Client) under the direction of the Design Consultant Item Question Q1 Do you have experience with Underground rail network ventilation resilience? Requirement: Ventilation Resilience Report required for the HAL Rail underground network. Q2 What capability do you have of air flow modeling for fans / attenuators etc.? Requirement: Model the existing configuration with one fan operating, and both fans operating and then repeat the modelling with shaft sub divided to allow one set of attenuators to be replaced while the other is operational. Q3 What capability do you have of understanding the requirements for specifying replacement attenuators etc., Specifically considering the constraints of an operational rail network? Note: - RIBA 5 onwards including construction is excluded.",
        "datePublished": "2026-06-02T10:20:04+01:00",
        "status": "active",
        "classification": {
            "scheme": "CPV",
            "id": "71320000",
            "description": "Engineering design services"
        },
        "items": [
            {
                "id": "1",
                "deliveryAddresses": [
                    {
                        "region": "London",
                        "countryName": "United Kingdom"
                    }
                ]
            }
        ],
        "minValue": {
            "amount": 2500000,
            "currency": "GBP"
        },
        "value": {
            "amount": 5000000,
            "currency": "GBP"
        },
        "tenderPeriod": {
            "endDate": "2026-06-09T21:34:00+01:00"
        },
        "contractPeriod": {
            "startDate": "2026-08-07T00:00:00+01:00",
            "endDate": "2026-12-01T23:59:59Z"
        },
        "suitability": {
            "sme": true,
            "vcse": true
        },
        "mainProcurementCategory": "services",
        "documents": [
            {
                "id": "1",
                "documentType": "tenderNotice",
                "description": "Opportunity notice on Contracts Finder",
                "url": "https://www.contractsfinder.service.gov.uk/Notice/2a1ded63-c1d7-4984-9540-4dd819838020",
                "datePublished": "2026-06-02T10:20:04+01:00",
                "format": "text/html",
                "language": "en"
            },
            {
                "id": "2",
                "documentType": "tenderNotice",
                "description": "Please follow this link to view the notice.",
                "url": "https://www.competefor.com/business/viewOpportunityDetailsSupplier.html?id=113536291"
            }
        ]
    },
    "parties": [
        {
            "id": "GB-CFS-271218",
            "name": "Costain Limited (H7-Heathrow)",
            "identifier": {
                "legalName": "Costain Limited (H7-Heathrow)"
            },
            "address": {
                "streetAddress": "Costain House Vanwall Road",
                "locality": "Maidenhead",
                "postalCode": "SL64UB",
                "countryName": "UK"
            },
            "contactPoint": {
                "name": "Teik Tan",
                "email": "teik.tan@costain.com",
                "telephone": "+447901130091"
            },
            "roles": [
                "buyer"
            ]
        }
    ],
    "buyer": {
        "id": "GB-CFS-271218",
        "name": "Costain Limited (H7-Heathrow)"
    }
}