---
title: "Porton - Main Plenum Replacement (North-East Wing)"
ocid: "ocds-h6vhtk-07837a"
canonical_url: "https://d3tenders.com/contract/?ocid=ocds-h6vhtk-07837a"
markdown_url: "https://d3tenders.com/contract/ocds-h6vhtk-07837a.md"
json_url: "https://d3tenders.com/contract/ocds-h6vhtk-07837a.json"
source: "Find A Tender Service"
current_stage: "Award"
buyer: "UK Health Security Agency"
published: "2026-10-08"
---

# Porton - Main Plenum Replacement (North-East Wing)

Buyer: UK Health Security Agency  
Current stage: Award  
OCID: ocds-h6vhtk-07837a

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## Summary

The UK Health Security Agency is procuring building works at Building 1, Porton Down: complete replacement of asbestos-contaminated supply and extract ductwork in the North-East Wing phase of its Main Plenum Replacement project. The work covers both supply and extract ducts and is a full replacement, rather than a limited repair. It sits within the agency’s wider project to replace the building’s main plenum. The requirement is specifically for the North-East Wing at Porton Down, so it is most relevant to contractors able to deliver building and mechanical services work at this site, including work involving contaminated ductwork.

The procurement is complete and the contract was awarded directly to Limburn Boiler & Heating Services Ltd. The buyer justified a direct award for additional or repeat works: changing supplier could result in incompatible works and disproportionate technical difficulties in operation or maintenance. The award date was 8 October 2026. The awarded value is £7,000,000. The contract period runs from 22 October 2026 to 30 July 2027, with signature scheduled for 22 October 2026. There is one lot, and the procurement was considered suitable for SMEs and voluntary, community and social enterprises. The published data gives no separate scoring or evaluation criteria for comparing bids.

This award shows demand from the UK Health Security Agency for major building works involving full replacement of contaminated supply and extract ductwork at Porton Down. Limburn Boiler & Heating Services Ltd, an SME, was selected through a direct award because continuity with the existing supplier was considered important to avoid incompatibility and disproportionate technical difficulties in operation or maintenance. A supplier competing for a similar requirement from this buyer would need credible building-services delivery capability, including the technical capacity to replace supply and extract ductwork in an asbestos-contaminated setting. Experience managing the interfaces with existing systems and the operational risks of changing contractors would be commercially relevant, as would the capacity to undertake a substantial, site-specific package of works.

## Notice

Full replacement of the asbestos contaminated supply and extract ductwork in the North-East Wing (NEW) Phase of the MPR Project, Building 1, Porton Down

### Procurement Information

Sch. 5 para. 7 - Additional or repeat goods, services or works The public contract concerns the supply of goods, services or works by the existing supplier which are intended as an extension to, or partial replacement of, existing goods, services or works in circumstances where (a) a change in supplier would result in the contracting authority receiving goods, services or works that are different from, or incompatible with, the existing goods, services or works, and (b) the difference or incompatibility would result in disproportionate technical difficulties in operation or maintenance.

## Key Details

| Field | Value |
| --- | --- |
| Publication source | Find A Tender Service |
| Latest notice | https://www.find-tender.service.gov.uk/Notice/095092-2026 |
| Notice type | UK6 - Contract Award Notice |
| Procurement type | Standard |
| Procurement category | Works |
| Procurement method | Direct |
| Procurement method details | Direct award |
| Tender suitability | SME, VCSE |
| Awardee scale | SME |
| All stages | Award |

## Dates

| Field | Value |
| --- | --- |
| Publication date | 8 Oct 2026 |
| Submission deadline | Not specified |
| Future notice date | Not specified |
| Award date | 8 Oct 2026 |
| Contract period | 22 Oct 2026 - 30 Jul 2027 |
| Recurrence | Not specified |

## Values

| Field | Value |
| --- | --- |
| Tender value | Not specified |
| Lots value | Not specified |
| Awards value | £7,000,000 |
| Contracts value | Not specified |

## Status

| Field | Value |
| --- | --- |
| Tender status | Complete |
| Lots status | Complete |
| Awards status | Pending |
| Contracts status | Not specified |

## Buyer

| Field | Value |
| --- | --- |
| Main buyer | UK Health Security Agency |
| Locality | LONDON |
| Postcode area | East London |
| Postcode | E14 4PU |
| Country | England |
| ITL 1 | TLI London |
| ITL 2 | TLI4 Inner London - East |
| ITL 3 | TLI42 Tower Hamlets |
| Local authority | Tower Hamlets |
| Electoral ward | Canary Wharf |
| Westminster constituency | Poplar and Limehouse |
| Delivery location | Not specified |

## Supplier

| Field | Value |
| --- | --- |
| Number of suppliers | 1 |
| Supplier names | LIMBURN BOILER and HEATING SERVICES LIMITED |

## CPV Codes

### Divisions

- 45 - Construction work

### Codes

- 45210000 - Building construction work

## Release History

- 8 Oct 2026 at 11:10 - Award - UK6 - Contract Award Notice - https://www.find-tender.service.gov.uk/Notice/095092-2026
- 8 Oct 2026 at 11:04 - Award - UK5 - Transparency Notice - https://www.find-tender.service.gov.uk/Notice/095080-2026

## Documents

- https://www.find-tender.service.gov.uk/Notice/095092-2026
  8th October 2026 - Contract award notice on Find a Tender
- https://www.find-tender.service.gov.uk/Notice/095080-2026
  8th October 2026 - Transparency notice on Find a Tender

## Notice URLs

- https://www.gov.uk/government/organisations/uk-health-security-agency
- https://www.legislation.gov.uk/ukpga/2023/54/contents

## Provenance

This Markdown file is an alternate public rendering of the D3 Tenders contract record. The canonical page is https://d3tenders.com/contract/?ocid=ocds-h6vhtk-07837a. The underlying structured data is available as OCDS JSON at https://d3tenders.com/contract/ocds-h6vhtk-07837a.json.