1 High Street

The Main Character

An office to residential permitted development scheme. A local business owner had operated out of a high street premise for many years but the property was not designed as a modern office so the spaces weren’t ideal for creating a modern office environment and buzz. He felt that his sales team especially had outgrown the space and he wanted to purchase a new office space which would allow them to create the right environment to grow his company. 

So he considered selling his property but was disappointed in the value of commercial property on the High Street, they have changed so much over time. He looked at how he could maximise the value of his office so he could purchase a new larger office for his staff. He approached us to find out what was feasible and through a feasibility study, we were able to demonstrate that it was possible to convert the space into residential units. Other companies he had approached had only considered converting the existing office into residential, whereas we saw the opportunity to create additional space through an airspace development to the rear. This changed the development from 7no. flats to 9no. flats a 30% increase on Value.

We had an existing developer client working on another project and were able to utilise our network for the benefits of both parties by avoiding pitfalls of open market selling and achieve a mutually beneficial result. We marketed the opportunity to our network and were able to negotiate the sale of the site on a subject to planning basis.



The Setting

It is 19th Century red brick with pitched slate roof, a three-storey property, previously a Solicitors’, with a traditional strong room and safe. It is not listed but is a fine example, typical of its age and traditional style. Located on the upper end of the High street, previously used as an office by a local business, and located next to a public house, other commercial uses and other residential conversions.

The High Street can be found on a prominent location in a Conservation area, and whilst it is not listed, due to its age and location was noted as a building of townscape merit in the conservation area appraisal and any plans had to respect the facade, whilst maximising the developable area and without impacting the street scene.

The Challenge

Office to Residential Permitted Development

From a stringent local authority planning team, to difficult highways constraints, conservation considerations and an intricate existing building the project demanded creative solutions from the whole team

An office to residential conversion is a change of use under Permitted Development, the change of use is subject to submitting a Prior Approval to the local authority to prove there are no issues with contamination, flooding, or highways. 

The site had only a few metres of amenity space and no viable private parking, only a public car park a short walk away. Through thorough research, we were able to show that the site is in a sustainable location, as it is within easy walking distance of the local bus and train station, and so we were able to agree to a zero car scheme.

To make the sale of the property stack for all parties, the scheme needed to achieve nine units but fundamentally there wasn’t room in the existing space.  The original structure lent itself well to natural division and we were able to create seven homes, a mixture of studios and one-bedroom flats under permitted development rights through a certificate of lawfulness. To get to nine units to maximise the development a follow up planning permission for the additional two units was submitted, the team had to work to tight timescales due to the purchase agreement and the staged approach complicated the matter. 

Whilst the Permitted Development was relatively straight forward, even with the usual debate with Northamptonshire highways, whereas the permission for the airspace development to create the additional two units, involved designing in a conservation area and required bringing the conservation officer on board. This is because the extension was significant in size, which created additional build cost, and we were made to replicate the existing architectural detailing, such as string courses, the stonework, and the sash windows’ proportion and size.

To compound the challenge even though the Permitted Development was granted the local authority wouldn’t agree to Planning Permission until the Permitted Development was implemented because they were concerned that they may end up with an office that had a residential extension. As such there were additional costs faced in enacting the Permitted Development, for example, inspecting the staggered works where a single approach would have been more cost-effective and having to redesign the airspace development to separate it from the main building.

Having helped the developer to achieve planning permission our planning and architectural team then helped to prepare a Building Regulations package, which the developer tendered out. The tender responses were so varied that the developer decided to manage the construction themselves.

Feedback from the developer was that although the existing structure was great to work with it had its own challenges for example having to work with a building which had no standard make up. Whilst working with the new build has a perceived higher cost it was less complex due to standardisation and in the end cheaper. Specific issues which arose were complex drainage designs, requirements for fire safety (installation of misting suppression systems, AOV), installation of MVHR system throughout the building. Feedback from the client was that even though these issuess arose we were able to support them throughout each element to ensure a compliant yet commercially viable solution.

The Return

Office to residential permitted development

Having achieved planning permission and having helped achieve building regulations plans, we provided ad hoc architectural support when required but also introduced the developer to our construction management team who spent time briefing their construction team on-site setup, health and safety and best practice before pointing their team towards the relevant courses to ensure they would have everything they would need to do to manage the build effectively.

Having successfully managed the conversion and new build we assisted with collateral warranties for the funder and purchase.

We were able to keep professional fees low by only producing the information needed, as part of our service for example for permitted development you don’t have to provide detailed layouts, so whilst the plans created 7 homes in a sustainable location the developer did not need to spend money on superfluous detail at this early planning stage.

The Final Twist

The staged approach meant that when the developer purchased the site it had permission to create an extension to the rear with its own access, however this meant the client lost considerable sales value in the floor areas, so we hastily submitted a revised permission to remove the separate access and improve the floor area. 

This redesign meant that our client was able to negotiate the sale of the whole block to an assisted living  provider, speeding up his exit markedly.


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