Class AA – New storeys on detached buildings in commercial or mixed-use

The Class AA Building Regulations Explained

Class AA – New storeys on detached buildings in commercial or mixed-use (shops and flats)

We always want to keep business owners and property developers in the know for new opportunities. With the ever-increasing population, it seems that ‘going up’ is the only way to alleviate the housing problem.  Today we want to talk about airspace and the available opportunities within the GPDO.


There have been updates to the legislation concerning building new flats in airspace across England and there are possibilities for you to expand your home or shop.


Heads up: Class AA is all about rights concerning upward extensions.


What does the new building regulation say?

Earlier this year, the Government released a series of updates on new permitted development rights regarding the enlargement of existing dwelling houses and commercial properties by building additional storeys.


The Permitted Development rights let existing detached, semi-detached properties or a terrace be expanded upwards providing additional living space.


This legislation comes as a way to provide more room for growing families in the UK as well as hoping these measures help support financial recovery from the coronavirus pandemic by promoting development.


What does this mean and what are you allowed to do?

Class AA allows you to build up to two new storeys of flats above the airspace of an above detached building. Additionally, The property you are looking to expand can be commercial or mixed-use (residential use included).

Essentially, we are looking at the possibility of having shops with 2 storeys of flats above them or additional retail space. The max height of the finished development is 30 metres.  Keep in mind we are talking about developing storeys above ground, anything underground is omitted.


Which properties can’t make use of Class AA?

Of course, Permitted development rights are going to be subject to certain regulations and that will limit how much you can develop to protect local amenities.

Here are a few examples of areas where development is not permitted:

  • Conservation areas
  • National parks
  • Areas of outstanding natural beauty
  • Sites of special scientific interest.
  • The building was constructed before 1st July 1948 or after 5th March 2018
  • If the existing house has been enlarged by the addition of one or more storeys above the original house, whether in reliance on the permission granted by Class AA or otherwise.

Things to keep in mind:

The property must have been built between 1st July 1948 and 5th March 2018. Another thing that comes into the equation is that flats can’t be HMOs. That’s a whole different set of rules, we know they make great investments, but for that, you’ll require full planning.


How to Apply for Use Class AA?

Now, If you read this far, you must be excited about expanding your property. I mean, with this attractive option who wouldn’t be? But before you go ahead and start making plans for extra storeys to accommodate your parents, your development plans need to be revised carefully by a professional prior to going for a Use Class AA application.

Prior approval from the local authorities is required for Use Class AA.


This is what you need to supply them:

  • Floor plans
  • Number of dwellings and list of all flats in the block
  • Flood risk report (if required)


Processing time: Results upon the application will be decided within 8 weeks or 56 days.


What do we think about Class AA?

Class AA is a great opportunity to allow homeowners and businesses to grow their properties within the available airspace and alleviate housing issues and quality of living. We also think it’s an impressive initiative for small developers to promote house extensions and help them recover from the COVID-19 pandemic.

If you think you comply with the requirements why don’t you get in touch with us? We will love to get you more familiar with the full legislation.


Post a Comment

Call us