Pumping Station, Pangbourne
Cohanim Architecture's involvement at Churchill Island extended considerably beyond the conventional architectural appointment. The property was acquired as a derelict former commercial building with an unsuccessful planning history, significant flood-risk considerations and a long-standing Environment Agency lease affecting part of the building. Working alongside the owner from acquisition through to disposal, we developed and implemented a strategy which established residential use, substantially increased the consented accommodation, resolved key planning conditions, progressed the scheme through Building Regulations and assisted with the management of the third-party occupational interest. The resulting consent established a five-bedroom detached dwelling of approximately 207 sq m before the development opportunity was successfully sold in 2023.
The initial objective was to establish whether an unattractive and heavily constrained commercial asset could be repositioned as a viable residential development. The brief quickly developed beyond securing a change of use. It required us to understand the previous unsuccessful planning history, assess the architectural and heritage value of the existing structure, respond to its waterside and flood-risk setting and determine how substantially greater residential accommodation could be achieved without losing the principle of development. Our role ultimately extended across acquisition advice, architecture, planning strategy, condition discharge, statutory coordination, Building Regulations, lease and asset-management matters and preparation for disposal.
Unlocking a constrained asset rather than simply redesigning a building The site combined several constraints which materially affected its development potential. The existing building was derelict and commercially redundant, but had been identified as having local architectural and historic interest. Previous attempts by another owner to establish residential use through permitted-development routes had failed or been withdrawn. The River Pang directly adjoined the site, introducing a significant flood-risk consideration, while part of the building remained subject to a 125-year Environment Agency lease dating from 1989. The challenge was therefore not a single architectural problem. It was to progressively remove or control each constraint until the property had a clear residential use, an enhanced consented envelope and a sufficiently resolved statutory position to constitute a deliverable development opportunity.
A redundant building on an unusual waterside site
Churchill Island sits in the heart of the historic centre of Pangbourne, where branches of the River Pang surround the site and give it an unusually private waterside setting. The site lay within Flood Zone 3 by virtue of its proximity to the River Pang, which adjoined it directly. The building had formerly been associated with Thames Water and had accommodated staff, storage and ancillary commercial uses. By the time of acquisition it was vacant, deteriorating, suffering from tenants who had long forgotten their lease responsibilities and visually disconnected from the predominantly residential character of the surrounding village. The site nevertheless contained the fundamentals of a valuable residential property: a detached building, private garden, waterfront setting and off-street parking within walking distance of Pangbourne station. The development strategy began by recognising and retaining those advantages while addressing the planning, technical and legal constraints which had prevented the site from reaching its potential.
Two unsuccessful attempts by the previous owner
Before Cohanim Architecture's involvement, the previous owner, their agent and architects twice sought to convert the building through permitted development. Neither route produced a consent, and the site remained vacant, derelict and without a viable way forward.
The previous owner sought prior approval to change the building from light industrial to residential use. West Berkshire Council refused it, as the building had not been shown to be in lawful light industrial use rather than ancillary to the pumping station, and a full planning application was required.
A second prior approval application followed for a three-bedroom house. It drew an objection from the Pangbourne Flood Warden on flood risk, highway safety and parking, including parking proposed within the Environment Agency's leased space, and was withdrawn before determination. The previous owner then attempted an appeal, which was dismissed. At that point they effectively gave up and disposed of the asset with no material gain.
The property was acquired at auction in 2021 as a derelict commercial asset, with two unsuccessful applications behind it and an existing Environment Agency tenancy. Where the previous owner, agent and architects had not found a route to consent, we saw an opportunity. Before designing, we reviewed the title, previous applications, consultation responses, flood constraints, existing building and likely residential value. Auction due diligence was supported by a housing economic viability model to advise on value, cost and development potential, site surveys including a topographical survey, and a site-specific Flood Risk Assessment by Stantec drawing on Environment Agency modelled data, which demonstrated the development would be safe. This established a new strategy based on a full planning application and high-quality proposals, rather than repeating the permitted-development approach that had failed twice.
A full planning application was prepared for the change of use of the vacant sui generis building to a single dwelling, in place of the permitted-development route that had failed twice. West Berkshire Council granted planning permission on 19 November 2021, securing the residential principle at the first attempt, in a decision made in a positive way to foster the delivery of sustainable development. The consent addressed heritage, flooding, parking, construction management and residential amenity while retaining and adapting the existing building.
With the principle secured, a second full application raised the single-storey wing into a mansard storey, transforming a modest conversion into a five-bedroom detached family house. The Conservation Officer found the balance in favour, noting the proposals would ensure a viable future use of a non-designated heritage asset of local interest. The case officer concluded there would be no harm but actually a localised visual improvement, and that the scheme would bring back a disused building to life. Pangbourne Parish Council raised no objection, and permission was granted on 7 April 2022.
Detailed design development was captured through a non-material amendment rather than a fresh application. Altered and additional windows on the front elevation, removal of the sliding storage door, revised rooflight positions and an improved internal arrangement were approved as non-material on 25 May 2022, improving the scheme without reopening the principle of the permission.
The details reserved by the mansard permission were discharged promptly, keeping the enlarged scheme ready to build. The Construction Management Statement and the boundary fencing that protects neighbouring gardens were approved on 6 June 2022, the fifth consent in a sequence in which each built on the last.
The project was progressed beyond planning into Building Regulations and technical coordination. A Full Plans application covered the conversion and upgrading of the derelict structure together with the consented extension. Building Control granted conditional approval in June 2022. The technical work addressed structure, fire safety, moisture protection, drainage, energy performance, accessibility and the unusual relationship between the building and the adjacent watercourse. Subsequent architectural and consultant information continued to develop the scheme towards an implementable construction package.
The reserved details followed within weeks of the permission. The Council's Conservation Officer agreed the proposed materials, including weathered clay tiles, timber box sash windows, conservation rooflights and matching brickwork, and the Highways Officer agreed the Construction Management Statement. Conditions 5 and 7 were discharged on 25 January 2022, clearing the way to begin.
As a non-designated heritage asset within the historic mill complex, the building was recorded before works began. The Council's Archaeologist approved the building recording report for the old mill building, and the archaeology condition was discharged on 23 August 2022, completing the sixth consent without a single refusal.
The site was disposed of to a local developer who commenced and completed construction within 9 months. Works were completed to a different specification with a lower budget without the firm's involvement. Given that we no longer were involved with the scheme following disposal, this was unfortunate but we are proud of the role we played in giving this heritage asset a new lease of life in any event and are delighted to see that the building is now happily tenanted.
Securing the principle, then increasing the value
The decisive move was to separate the development strategy into stages. Rather than beginning with the largest possible proposal, the first application concentrated on establishing the difficult principle: changing a vacant former commercial building into residential use. Once that principle had been secured, a second application was used to increase the building's accommodation through a new mansard storey and revised architectural composition. That sequence materially reduced planning risk. Each subsequent consent built on an established position rather than asking the Local Planning Authority to accept every element of the development in a single application. The result was a significantly larger and more valuable residential development while retaining the existing building and its local architectural character.
Resolving a long-standing occupational constraint
Part of the building had been subject to an Environment Agency lease dating from 1989. The lease formed part of the acquisition and, irrespective of the planning position, prevented the thorough redevelopment of the building: while it remained in place, the consented scheme could not be delivered in full and the property could not be disposed of with vacant possession. The occupational position was therefore managed alongside the architectural and planning work as a direct hurdle to delivery, rather than treated as a separate issue. In November 2022 the landlord exercised its rights of peaceable re-entry and forfeited the lease. The Environment Agency subsequently pursued relief from forfeiture, requiring continued coordination of the property, legal and development positions. We also managed the application to HM Land Registry to close the leasehold title following the forfeiture of the lease. This work formed part of the wider strategy to rationalise the asset and remove constraints affecting its future development or sale.
From planning consent to a deliverable scheme
Planning approval was treated as one stage in the development process rather than its conclusion. The approved concept was developed through Building Regulations, structural coordination, drainage and flood-risk requirements, architectural detailing and specialist historic-building recording. Particular attention was required where statutory requirements overlapped: finished floor levels and flood mitigation had to remain consistent with the planning consent, while Building Control requirements for structure, energy, fire safety and accessibility needed to be incorporated without undermining the approved external appearance. This technical development materially improved the quality of information available to a future contractor or purchaser.
Preparing the development for disposal
Following the planning and technical value-add programme, the property was prepared for sale as an undeveloped residential development opportunity. Our involvement continued through the disposal process, including coordination of technical and planning information, preparation of development material, liaison with the selling team and responses to purchaser due diligence. The property was successfully disposed of in 2023, completing a development cycle which had begun with the acquisition of a derelict and constrained commercial asset approximately two years earlier. The disposal delivered an approximate net profit of £300,000 for the client, achieved in around 18 months and without the need to commence construction.
What the project delivered
Chronological summary
| Date | Reference / Matter | What was achieved |
|---|---|---|
| Jun–Jul 2021 | Acquisition | Freehold commercial property acquired following auction process, subject to the existing Environment Agency lease |
| Aug 2021 | Development strategy | Previous unsuccessful planning history reviewed and full-planning strategy established |
| 19 Nov 2021 | 21/02191/FULD | Full planning permission granted for change of use from vacant / sui generis building to a dwelling |
| 25 Jan 2022 | 21/03003/COND1 | Materials and Construction Management requirements approved |
| 7 Apr 2022 | 22/00056/FUL | Planning permission granted for first-floor mansard extension and alterations, materially increasing residential accommodation |
| 25 May 2022 | 22/00917/NONMAT | Window, rooflight and internal-layout refinements approved as non-material amendments |
| 6 Jun 2022 | 22/00916/COND1 | Construction Management Statement and boundary/fencing details approved |
| 29 Jun 2022 | 22/1618/MULFP | Full Plans Building Regulations submission conditionally approved |
| 23 Aug 2022 | 22/01793/COND2 | Historic-building / archaeological recording condition fully discharged |
| 5 Nov 2022 | Environment Agency lease | Peaceable re-entry undertaken and the 1989 lease forfeited |
| 2022–23 | Technical development | Building Control, structural, drainage, flood, energy and architectural information developed |
| 2023 | Lease / asset management | Subsequent Environment Agency relief-from-forfeiture proceedings managed alongside liaison with HM Land Registry on the application to close the leasehold |
| 2023 | Disposal management | Marketing, technical information, purchaser enquiries, CPSE and legal due diligence coordinated |
| Q3 2023 | Disposal | Undeveloped consented property successfully sold, delivering an approximate £300,000 net profit without commencing construction |