Is building in airspace the future?

extension of a apartment house with large dormers

Building products looks at the impact that ‘building in airspace’ will have following the new permitted development rights (PDR) brought in by government.

Building upwards has long been something touted as a solution to the UK’s housing problem; and an approach that has long been adopted in other countries. Now seemingly keen on the idea government recently confirmed that a new permitted development right (PDR) would allow upward extensions of two-storeys on existing blocks of flats.

Coming into effect on August 1 2020, the new PDR enables property owners to progress with upward extensions of two additional storeys on detached blocks of purpose-built flats without the need for planning permission.

Such developments remain, however, subject to a number of approvals and there are exceptions. It is knowledge of these intricacies, that Click Above believes has positioned it as a go-to source for enquiries.

Those in favour of the move say it could help with the UK’s chronic shortage of housing, although there are no guarantees any new developments will be aimed towards first-time buyers or those struggling to acquire housing.

Laith Mubarak is Click Above’s Acquisition’s Director and leads on the firm’s rooftop acquisition strategy.

Click Above is an airspace developer.

He comments: “This isn’t simply a case of throwing up prefabricated units to increase housing supply and the enquiries we’re fielding are from prospective partners who appreciate the potential of this exciting development.

“Whether we’re talking to private freeholders, social landlords or local authorities, their concerns are often the same: ‘is my building suitable for this type of extension?’,‘how will the existing residents be affected?’ ‘how long will there be on-site disruption for?’ and ‘can I engage with a single team to realise the successful completion of such a project?'”

The new PDR is subject to a number of exclusions that include buildings that have become residential only after a previous change of use; the existing building being less than three storeys in height and must contain flats; the building being constructed before July 1948 or after March 2018; or the building being located within a Conservation Area (or similar).

There are also several clauses that must be adhered to with regards to the dimensions of the extension.

Many in the sector have been asking what is next and could the legislation eventually cover other buildings.

Hinesh Chawda, who is Director at Life Less Ordinary, a boutique property developer, comments: “Legislative changes around permitted development rights should never be solely focused on going further, building higher or pushing the boundaries simply because it’s possible.

“We started Life Less Ordinary by identifying the opportunity to utilise PDRs to develop high-quality office to residential conversions, primarily for the first-time-buyer market.  We have subsequently moved into traditional development as well as airspace development, where we convert the unused airspace above existing properties into well-designed new homes.  The key is that any PDR should only ever exist to deliver a positive outcome, all within the confines of meeting a need and delivering a quality end-product.  Whilst current PDRs achieve that, I can’t foresee a need to add further changes.”

To find out more about the potential impact it will have in regards to the construction of new buildings, Jo Davis – who is National Head of Planning, Development and Regeneration at Avison Young – comments: “The impact of the PDR for upward extensions is unlikely to have a significant impact on the construction of new buildings as it is only existing in purpose-built detached blocks of flats.

“More important is the new Class ZA that has been introduced for the demolition and rebuild of vacant blocks of flats or detached employment buildings. Whilst this would not require planning permission, it would require a Prior Approval application and there are a number of factors that must be considered including design and external appearance, impact on neighbouring amenity and the provision of appropriate levels of daylight to new houses and flats. There are restrictions to when this right can be used, but in allowing for demolition and redevelopment of existing buildings, it will be an important route to consider for owners of such buildings.”

Jo continues by saying there are several hurdles that need to be met before you can build.

She says: “The overall height of the extended building cannot exceed 30m in height and the extension should not be more than 7m in height with each additional storey limited to 3m in height or the height of any existing storey, whichever is the lesser.

“There are also several matters that should be satisfied through a Prior Approval process, not least demonstrating that adequate natural light is provided to new dwellings. A separate part of the new legislation also requires that the amenity of neighbouring occupiers in terms of daylight/sunlight is considered through a prior approval process.

“In practice, the changes cannot be used on mixed use developments, for example, a block of flats with a non-residential ground floor use, which is often incorporated into development to add to street level activity. This may limit how many developers seek to pursue this approach and may limit its use to smaller blocks of flats particularly as there is an alternative of demolition and redevelopment.

“It may however benefit local authority or housing association-owned blocks of residential flats where it gives the potential to increase the number of affordable homes being developed.”

Jo does say though that the move is a clear sign that government is laser focused on boosting the sector.

She comments: “Overall, the introduction of the new PD right shows Government support for density and building upwards in cities and will feed into the debate around whether ‘up’ or ‘out’ into the Green Belt is the correct approach for new homes. It is clear given the timing of the changes and the Prime Minister’s ‘Build, Build, Build’ speech that the impetus is to stimulate economic recovery and increase levels of construction.

“The challenge will be in the detail and the level of information needed to demonstrate to a local authority that the impacts are acceptable, particularly on daylight/sunlight. Local authorities will need to meet this challenge by ensuring that planning officers are fully trained in interpreting and assessing daylight impacts including compliance with any BRE Guidance.

“This will be a critical element of any prior approval application and is a more onerous requirement than seen previously.

“As there are subjective judgments that would need to be made through the prior approval process, for some developers it may be more effective, with a greater chance of a well-designed and successful outcome, to prepare a full planning application collaboratively with a local authority.”<