What Is Sui Generis Planning? (Secrets Of A Great Application)

Reading Time: 10 minutes

Are you a property investor looking to develop larger properties? Does the term Sui Generis Planning scare or put you off? 

While the term Sui Generis applies to many types of properties, this article mainly focuses on HMOs (house of multiple occupation). 

With a primary aim to provide quality housing and make a good return, you can see why smaller properties may not be worth it. 

With the regulations and risks involved, why wouldn’t you go after something that has the potential to change your life? 

A single large HMO can net you £2,000+ per month leading to financial freedom from one deal. 

If you’re a serious property investor looking to develop larger HMOs, this article applies to you. 

I’ll talk about Sui Generis Planning, what it is, types of properties under this class and how it differs from a standard C3 to C4 Change of Use. 

Most importantly I’ll share valuable tips and advice on how to prepare a solid Sui Generis Planning Application that maximises your chance of approval. 

Lastly, I’ll also share some common objections from the Council and my insider tips and advice on how to overcome them. We’ll end with a real case study and learnings. 

So buckle up, grab a coffee and read on. 

Jump To 

What Is Sui Generis Planning?

What Comes Under Sui Generis?

Can You Change Use Within Sui Generis?

How Is A Sui Generis Planning App Different From C4?

Key Considerations for a Successful Sui Generis Planning Application

Note On Listed Buildings

Main Obstacles In A Sui Generis Planning Application And How To Overcome Them

Sui Generis HMO Case Study (Nightclub to HMO Conversion)


What Is Sui Generis Planning?

Sui Generis Planning is a planning application for the Change Of Use of a property from one Use Class To Another under the Sui Generis category. 

Sui Generis Use Class includes non-standard buildings that don’t have a category for example theatres, nightclubs, hostels. 

HMOs with more than 6 occupants are classed as Sui Generis and need Sui Generis Planning. 

What Comes Under Sui Generis?

The word “Sui Generis” comes from a Latin word that translates to “in a class of its own”. 

According to the Planning Portal, there are several types of property that can be classed as Sui Generis. 

For example 

  • fuel stations 
  • taxi businesses 
  • nightclubs 
  • casinos 
  • betting offices/shops 
  • payday loan shops 

And lots more. Please check out the Planning Portal for a non-exhaustive list. 

HMOs with up to 6 occupants are classed as C4 Use Class. Meaning HMOs with more than 6 Occupants are classed as Sui Generis. 

This Class of property developments attract more regulations such as good acoustics and a solid fire compliance strategy. 

Can You Change Use Within Sui Generis?

No, you cannot change the use of a property within Sui Generis without a full planning application.  

If you want to change the use of a Sui Generis HMO into a nightclub or vice versa you need a Full Planning Application.  

Even if you want to change the number of occupants of an existing 10 Bed HMO, from 10 to 12, you need a Full Planning Application or a Non-Material amendments application on the previously approved 10-bedroom HMO Application 

Every property is unique and must be compliant with local planning/licencing regulations.  

How Is A Sui Generis Planning App Different From C4?

You may be wondering, a Sui Generis Planning application must be the same as a standard C4 one, right? 

Not quite. A standard C3 to C4 Conversion can often fall under Permitted Development Rights (PD). 

This means you can change the use class from C3 (single dwelling) to C4 (HMO) without a full planning application  

(unless located in an Article 4 Area – which removes the Permitted Development Rights). 

Often some rear extensions or permitted development loft conversions fall under these. 

Sui Generis is a complicated Use Class of properties and the planning requirements are different. 

Sui Generis HMO use is effectively closer to commercial use than purely residential use, that’s why the requirements are much stricter. 

From structural requirements to acoustics, fire, transport and parking, the requirements are stringent and tight. 

This is due to a higher number of people living in the house which influences the local area and community. 

Key Considerations for a Successful Sui Generis Planning Application

Now you’ve had an intro to the Sui Generis Use Class, Planning and how it differs from a standard C3 to C4 Planning Application. 

So, what do you need to submit to maximise your chance of a successful Sui Generis Planning Application? And to what level of detail? 

Let’s take a look now. 

Drawings (Required)

One of the most important things you need is good drawings — Existing and Concept. 

Existing Drawings (plans, sections, elevations) show how the building looks currently and how it works before any intervention. 

The quality of drawings needs to be top-notch, understandable with the correct scale and level of detail. 

If you don’t have existing drawings you’ll need to do a Measured Survey which is done using a 3D Laser Camera to produce accurate measurements of the property. 

If you have existing drawings (in .DWG format) and you’re unsure if they meet the requirements for a planning app, you can have them converted and modified fairly easily. 

We always advise our clients to get the .DWG files of their drawings from their architects which can be helpful if you choose to work with another architect or measured survey company. 

Concept Drawings (plans, sections, elevations) show how the building is expected to look following the development. 

They take into account: 

  • Local HMO Licencing Standards 
  • Fire Requirements, Acoustic requirements, Some planning requirements (e.g. travelling distance from the kitchen to bedroom — should be less than 2 floors) 
  • Size of Bedrooms, Living Room, other communal areas 
  • Measurements of the floor areas 
  • Show what is retained of the previous building and what’s added (our standard in blue and grey). 

Good concept drawings showing the above are a key part of your Sui Generis Planning application. 

Lastly, an Ordinance Survey Map (OS Map) represents the location of the property in the neighbourhood on a scale of 1:1250 and is essential for the Council. 

Design and Access Statement (Required)

Alongside drawings, an important part of your Sui Generis Planning application is a Design and Access (DA) Statement. 

This is a document which explains the reasons behind our design solutions. 

A comprehensive DA Statement usually includes 

  • Analysis of the area 
  • Analysis of the constraints of the site i.e. conservation area, flooding risk, listed building 
  • Article 4 Regulations 
  • Local plan policies relevant for the proposal 
  • Diagrams showing the development 
  • Position of cars, bikes, parking 
  • Proximity to public transport 
  • Bins and waste 
  • Diagrams explaining the overlooking issues generated by extensions, loss of light towards neighbours 
  • Details of relevant planning history 
  • Diagrams showing the stacking principle (toilets above toilets, bedrooms above bedrooms- councils like these designs and they work better for acoustics and logistics of the drainage system 
  • Material selection (exterior — bricks/plaster/render, the facade, stone cladding, window colour, covering the dormer- slates/tiles, covering the roof — slates/tiles etc) 
  • Design guidelines (more about the geometry of any extension — designed while being considerate of the main building, extensions need to appear subordinate of the existing building, needs to appear smaller than the main building, set back and recess). 

As you can see from the above, a detailed Design and Access statement is key to a successful Sui Generis Planning App. 

The Council needs to know and understand that you’ve considered the possible impact of your HMO development on the surroundings, community and nature with clear action steps and accountability. 

HMO Management Plan (Nice to have)

Although not mandatory, some Councils request for an HMO Management Plan as part of the Sui Generis Planning Application. 

The Plan should contain detail on cleanliness, maintenance and how you plan to handle nuisance or anti-social behaviour from tenants. 

Also, details on the number of bedrooms (ensuites vs shared), tenancy agreements, waste management and parking plan. 

A detailed HMO Management Plan will show the Council you’re a professional landlord and have thought about the impact of your HMO Development on the Local Community. 

Transport Statement (Nice to have)

Another item on your list that can strengthen your application is a well-researched Transport Statement. 

Not mandatory but adds a lot of value. 

Transport Statements are produced by a transport consultant. It is a report that includes a study of the parking provision of the area. 

It defines the impact of occupants with the existing parking provision taking into account the parking spaces available on the plot and neighbourhood, proximity to public transport, cycle provision. 

It includes a stress test of your scheme showing the worst-case scenario and how you’d handle it. 

It tries to support the scheme as much as possible. 

Flood Risk Assessment (Depends on the area)

A flood risk assessment shows the Local Authority you have considered the impact of a flood on your development and helps support your Sui Generis Planning Application. 

There are several websites that can tell you the flood risk level of your property. 

For example, 

1 — Low Risk 

2 — Medium Risk 

3 — High Risk 

The Council generally asks for this only if your property falls in a High-Risk Zone in which case it’s required you submit one. 

Flood Risk Assessments are done by a Flood Risk Assessor. 

Note On Listed Buildings

Listed Buildings are defined by Historice England as 

A building is listed when it is of special architectural or historic interest considered to be of national importance and therefore worth protecting. 

These buildings call for extra protection and it’s often challenging to get a Change Of Use Application passed. 

The process is complicated, will need a heritage statement and consent from the Local Heritage Officer. 

There are restrictions on what you can do to the property and it’s another level of complexity that shouldn’t be underestimated. 

Getting Heritage approval can often add months to your Sui Generis Planning application. 

Main Obstacles In A Sui Generis Planning Application And How To Overcome Them

OK, let’s say you followed all the advice outlined in this blog and submitted a detailed Sui Generis Planning Application. 

Is it guaranteed to be approved? Of course not. 

Like most things, there is no guarantee. What this does is improve the odds of a successful application. 

From working on over 150+ HMOs with a 90%+ Planning success rate, I’ve had my fair share of objections. 

I’ve listed the most common objections to Sui Generis Planning Applications including strategies to solve them. 

Most Planning Consultants would charge ££ but I’ve decided to share. Hope it helps. 

Lack Of Parking Spaces

Parking is a major concern in urban areas. 

Imagine a street with 3 HMOs (each with 7 occupants). All of a sudden there are 21 cars. This makes it challenging (and annoying) for other local residents. 

Councils almost always object to this in your Sui Generis Planning app. 

How do you get around it? 

As discussed above, show a good Transport statement (proximity to public transport) and bike storage in your plans and Design Access Statement. 

This gives the Council confidence that your tenants likely won’t introduce double the number of cars on the street overnight. 


Neighbour Objections

Neighbours will almost certainly object to a large Sui Generis Planning Application. 

After all who wants a bunch of noisy or dirty tenants living next door? 

Once you’ve made a planning application, the public has the right to comment on it. 

Neighbours often group together and leave comments on your application stating why an HMO on their street isn’t a good idea. 

The Council then has to schedule a committee meeting to discuss the scheme with the representatives of the local committee. 

Your architect or I can support you with this. 

When the comments reach a certain number it becomes a political issue rather than planning and the Council may resist approving the application because of the opposition. 

As you see, this can become a serious issue with not much in your control. 

How can you minimise neighbour objection? 

Establish a friendly relationship with your neighbours from the beginning. Show them you’re a professional landlord, flyers or CGIs of the project with high-quality furniture for the best tenants. 

Share ideas with the community on how you can improve the quality of the neighbourhood with vetted tenants to mitigate risks of a nuisance. 

These small steps go a long way in satisfying your neighbours and reducing the chances of an objection. 

Overdevelopment Objections

Another objection raised by the Local Authority is overextension. 

Often a large Sui Generis HMO may include one or more extensions (rear extension, loft conversion, front extension, dormer conversion) to introduce more rooms. 

This can be considered the “overdevelopment” of the site. 

The recommended solution here is to reduce the size of the development. The more extensions or occupants, the longer is the planning process. 

If you wish to do a lot of extensions my recommendation is to go for a Pre Planning Application first to find out if the Council can allow these extensions, before submitting a Full Sui Generis Planning Application. 

Another strategy can be to subdivide the application into Permitted Development (PD) Rights and Planning. 

All properties have a PD right allowance — 6m rear extension, 3m rear extension, side extension on the ground floor, dormer extension, hip to gable extension). 

Once you’ve secured those then you can do the Full Sui Generis Planning Application. I always advise doing it in phases where possible. 

Of course, things change when there are Article 4 regulations in place. If you don’t know what is Article 4, I’ve got you covered. 

Sui Generis HMO Case Study (Nightclub to HMO Conversion)

With all the above information, you can see how these types of planning applications may be complex and take time and expertise to resolve 

I’d like to share a case study of one of my projects — A Nightclub to HMO Conversion

You can see how our team managed to transform this old run down Nightclub into a fantastic 12 Bed Sui Generis HMO cash flowing around £60,000 per annum. 

That’s life-changing, financial freedom right there. 

Our team dealt with pretty much most of the challenges I mentioned above but we were very glad to finally get this over the line for our client. 


I hope this Sui Generis Planning article gave you insight on how to plan for and submit a Sui Generis Planning Application for your HMO. 

We looked at some definitions around the Sui Generis Use Class, how it’s different from a C4 Use Class and how to craft a successful planning application. 

I also shared some common objections you’ll encounter during the process and how to deal with them. 

Lastly, we saw a Nightclub to 12 Bed HMO case study and how large HMOs can boost your income and change your life (when done right). 

If you’d like help with your Sui Generis Planning Application, please speak to me. 

Our expert team at HMO Architect have helped and advised many landlords with their HMO developments to provide some impressive cash flow and commercial valuation returns. 

So please get in touch. We’d love to help you too. 


10 Step Checklist To Prepare Your HMO For Tenancy & Maximise Cash Flow

Giovanni Patania

Giovanni Patania

(Architect Director, Co-Founder)

Giovanni Patania is the Lead Architect and Co-Founder at HMO Architect and Windsor Patania Architects.

Originally from Siena, Italy, Giovanni worked as a Project Lead Architect at Foster+ Partners, designing Apple stores across the world,

An HMO Investor himself, Giovanni understands property thoroughly, both from an investor's perspective and technically, as an Architect.

With over 15 years of HMO development experience, working on over 150+ HMOs and a 95% Planning and Building Regulation success rate, Giovanni has the expertise and credentials to help you on your HMO journey."



Other Recommended Articles For You