Tender

WP6235 -T5D MEP Subcontractor

COSTAIN LIMITED (H7-HEATHROW)

This public procurement record has 1 release in its history.

Tender

02 Jun 2026 at 09:30

Tender Notice
Summary of the contracting process

The contracting process involves Costain Limited (H7-Heathrow), seeking expressions of interest for the WP6235 -T5D MEP Subcontractor role. The procurement is aimed at delivering engineering design services, specifically for the T5D Rail-tunnel Ventilation Shaft located in London, United Kingdom. The primary goal is to replace the old attenuators to enhance safety and system resilience within the Heathrow Rail Tunnels. This tender, currently in its active stage, is part of the tender phase, with a tender period ending on 9th June 2026. The estimated contract value ranges from £2,500,000 to £5,000,000, with the actual execution period scheduled between 7th August 2026 and 1st December 2026.

The opportunity presents a significant chance for businesses in engineering design services, particularly those that can manage complex MEP systems within active rail networks. The project requires expertise in surveying and RIBA stage design, making it suitable for SMEs and VCSEs adept in such environments. By participating, businesses can establish or strengthen their presence in the infrastructure sector, leveraging their technical and logistical capabilities in a high-profile project like Heathrow, providing exposure and the potential for future contracts.

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Notice Information

Notice Title

WP6235 -T5D MEP Subcontractor

Notice Description

Expression of Interest T5D MEP Subcontractor T5D Attenuator Overhaul (Survey / RIBA 4iii) Scope 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 in 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 MEP Subcontractor under the direction of the Design Consultant (Employed by the Client). Item Question Q1 What capability do you have of understanding the requirements for replacing attenuators etc., considering the constraints of an operational rail network? Q2 What capability do you have of carrying out a survey of the T5D Shaft during non-operational hours to provide all the information required to complete the RIBA 4ii design by the Design Consultant and the RIBA 4iii by the MEP Subcontractor? * M&E Services within the air path * Fan and Attenuator * Structure Note: - RIBA 5 onwards including construction is excluded.

Notice Details

Publication & Lifecycle

Open Contracting ID
ocds-b5fd17-de6c09f3-6c96-4020-b334-051d5fc03d1d
Publication Source
Contracts Finder
Latest Notice
https://www.contractsfinder.service.gov.uk/Notice/e2e89ebe-cb92-4ba4-9e90-1788e7eaa3ad
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

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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. 

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