In short, the answer is yes, you can turn your house into one of multiple occupations without getting planning permission, but there are some important rules you need to understand first.
If your property is let to several tenants (3+) from separate households and some basic amenities are shared, then your property will potentially need an HMO licence from your local authority before you can start on any HMO conversion work.
Because HMOs involve different rules to standard property lets, you need to understand what’s required so you can make informed decisions, budget properly, and protect your investment. Let’s explore these rules and responsibilities in more detail before you pick up the hammer.
Looking for an HMO mortgage? Contact Simmonds Mortgage Services today to discuss your plans.
What types of HMOs (houses of multiple occupancies) are there?
There are three main types of HMO property:
- Shared house HMOs
The whole property is rented to a group of unrelated individuals, who each have their own bedroom but share communal areas such as the bathroom, kitchen facilities, and living rooms.
- Bedsit type HMOs
Separate, non-self-contained bedsits where the occupants have separate tenancies and don’t share a close bond. The facilities may be partly shared. - Section 257 HMOs
Self-contained flats within a converted building. Each unit has its own kitchen, bathroom, and WC, but the building does not comply with Building Regulations 1991, and less than two-thirds of the flats are owner-occupied.
More details on the different types of HMO properties can be found on the government website.
Do I need planning permission to convert my property into an HMO?
Currently (as of January 2026), you don’t usually require planning permission to turn a property into an HMO. Most HMO conversions fall under permitted development rights. But you should check with your local planning authority, as this is not always the case in some areas of the country. If the property falls within an Article 4 area, then planning permission may be needed.
If your property has seven or more unrelated tenants who share facilities, it may fall under Sui Generis planning rules. But remember, planning permission and licensing are two separate things, so you must always check both. And, the larger the HMO, the more complex the mortgage process can be.
See how we recently helped a Sui Generis HMO landlord get a much stronger mortgage after a previous inaccurate valuation stalled their refinancing plans.
Is my property suitable for an HMO conversion?
The HMO rules state that your property is an HMO if both of the following apply:
- Three or more tenants live there, forming more than one household
- Kitchen or bathrooms are shared
A household consists of either a single person or members of the same family who live together.
Your property is classed as a large HMO if:
- Five or more tenants live there, forming more than one household
- Kitchen or bathrooms are shared
If you rent your property to only one tenant, it does not count as an HMO property.
Getting an HMO licence
If your property houses five or more HMO tenants, you will need to obtain an HMO license from your local authority.
You will usually need to provide the following information:
- Valid gas safety certificate
- A fire risk assessment
- Evidence of working relevant smoke alarms and carbon monoxide detectors
- Safety certificates for all electrical appliances
- A valid energy performance certificate (EPC)
If you do not meet these legal requirements, you could get fined or lose your HMO license.
Building regulations
HMO conversions must comply with building regulations, especially if you’re changing the layout, adding bathrooms, or converting lofts or garages.
Local councils may assess structural safety, sound insulation, ventilation and escape routes. Always factor compliance costs into your budget before starting work.
Fire regulations
Fire safety is one of the most important aspects of an HMO conversion. It protects your tenants and reduces your risk as a landlord.
Properties must meet strict fire regulations, which may include:
- Fire doors
- Interlinked fire alarm systems
- Emergency lighting
- Clear escape routes
- Fire-resistant materials
Space and amenities
In 2018, the government introduced guidance on minimum room sizes to prevent overcrowding.
This means that individual sleeping accommodation must provide at least:
- 6.51 sq m per adult
- 10.22 sq m per couple
There are also set standards for other shared living spaces, such as communal areas, kitchens, living rooms, reception rooms, utility rooms, and bathrooms.
How to turn your house into an HMO conversion
HMO conversions offer an opportunity to make more monthly rent from your family home. However, HMO landlords must understand the additional restrictions and duties that are placed on them when they convert a property to accommodate several unrelated tenants.
Getting HMO ready
Before jumping in headfirst, it’s sensible to prepare your property and finances before advertising to prospective tenants. You’ll need to ensure the property is safe, compliant, insured and financially viable.
Below is a summary of the main areas to consider:
| Insurance | Specialist HMO insurance is needed to cover any issues or financial setbacks caused by a tenant. It protects you against losses on your HMO property investments and rental portfolio. |
|---|---|
| Safety | HMOs also require other safety features, including fire doors, emergency lighting, escape windows, exit signs, fire alarms and regularly maintained gas appliances with an annual gas safety check. These costs must be factored into your decision to convert your property for multiple tenants. |
| Taxes | HMO landlords are usually responsible for paying the council tax. This is another expense to consider when deciding how much rent to charge your tenants.You must also report any rental income you earn, so you need to understand how taxes affect your profitability. |
| Management | You may need help to find tenants. Many landlords use an agency or other tenant-finding service, which adds cost but saves time. |
| HMO mortgage | Before committing to a conversion, you’ll need a specialist HMO mortgage that matches how the property will be used. This is different to a standard buy-to-let mortgage because most lenders have specific rules around properties rented to multiple tenants. |
How much does an HMO conversion cost?
The true cost of converting a property into an HMO varies widely. It mostly depends on your budget, but it also comes down to the size and condition of your property, your timeline for carrying out the work, and the level of work needed.
Since costs can range from a few thousand pounds to significantly more, it helps to compare similar properties in your area to get an idea of what to expect.
Typical costs can involve:
- Building and refurbishment works
- Fire safety upgrades
- EPC upgrades
- Licensing and professional fees
- Mortgage fees
- Furniture and appliances
Can I get a mortgage to convert a property into an HMO?
There are special mortgage products for HMO housing. HMO mortgages, like traditional buy-to-let products, can also be offered at fixed, variable, and tracker rates. Fixed-rate deals usually run from 2 to 15 years, with monthly payments remaining the same during the fixed-rate period.
Interest rates are generally higher than those on standard buy-to-let products because renting to multiple tenants is considered higher risk. However, because more tenants pay rent, it helps offset the higher interest costs.
How can Simmonds Mortgage Services help with your HMO conversion?
Simmonds Mortgage Services are experienced mortgage brokers with access to specialist lenders in the HMO market. We explore high and low to help you find the perfect product for your investment property. Call us on 01184 693037 or use our contact form to get started.
