Converting a House into an HMO: Licensing, Costs and When Selling Beats Converting

*Collaborative Post

A three-bedroom house rented to one family might bring in around £1,300 a month. Rent the same property room by room to five people and the gross rent could be closer to £3,000.

However, higher rent comes with extra costs and responsibilities. You need to think about planning, licensing, room sizes, fire safety, building work and ongoing management. Some properties work well as HMOs, while others are too costly or cannot legally be converted.

What Counts as an HMO?

An HMO, or House in Multiple Occupation, is generally a property where three or more tenants from more than one household share facilities such as a kitchen, bathroom or toilet.

A household can be one person, a couple or members of the same family. Three unrelated friends sharing a house would normally create an HMO, while three siblings living together would usually count as one household.

Adding a third unrelated tenant can therefore turn an ordinary rental into an HMO.

In England and Wales, a property with five or more occupants from two or more households will generally require mandatory HMO licensing. Rules differ elsewhere in the UK, so check local requirements.

Planning Permission Comes First

A normal family home usually falls under planning use class C3. A small HMO for three to six people falls under C4. In many areas, changing from C3 to C4 is allowed under permitted development rights.

There are important exceptions. An HMO for seven or more occupants is normally classed as sui generis and requires planning permission.

Councils can also introduce an Article 4 Direction. This removes permitted development rights for HMO conversions in a particular area. It means you may need planning permission even for a smaller HMO.

Check your council’s planning policies and Article 4 map before paying for drawings or building work.

Licensing: Which Scheme Applies?

Different licensing schemes can affect an HMO.

• Mandatory licensing: This generally applies to HMOs occupied by five or more people from two or more households.
• Additional licensing: Councils can introduce this scheme to cover smaller HMOs, including some occupied by three or four people.
• Selective licensing: This can apply to privately rented properties generally within a designated area, not only HMOs.

Licence fees vary between councils and can cost around £500 to £1,500 or more for five years.

Operating without a required licence can lead to serious penalties. These may include substantial fines, civil penalties and rent repayment orders.

Minimum Room Sizes and Accurate Floor Areas

Bedroom size is an important part of HMO planning. In England, statutory minimum bedroom sizes for licensed HMOs include:

• One person aged over 10: At least 6.51 m².
• Two people aged over 10: At least 10.22 m².
• One child under 10: At least 4.64 m².

Areas where the ceiling is less than 1.5 metres high do not count towards the minimum floor area.

Councils can also set their own standards. They may require larger bedrooms where there is no separate living room.

Small measurement differences can decide whether a room can legally be a bedroom.

A measured building survey provides accurate plans and measurements. These drawings can support planning, licensing, building control and builders’ quotes.

Fire Safety and Building Regulations

Converting a property into an HMO can bring additional Building Regulations and fire safety requirements.

Depending on the property, you may need:

• Fire detection: Interlinked mains-powered smoke alarms and suitable heat detection in kitchens.
• Fire doors: Appropriate fire-resistant doors and self-closing devices where required.
• Protected escape routes: Occupants must have a safe way to leave the property during a fire.
• Fire risk assessment: The property should have an appropriate assessment of fire risks and safety measures.

Landlords must also consider gas safety, electrical inspections and energy efficiency requirements.

HMO-specific insurance may also be needed.

Loft and Roof Works

Many HMO projects involve roof work, especially when a loft conversion could create another bedroom.

Working at height must be taken seriously. Falls remain one of the main causes of fatal accidents in UK construction.

Suitable precautions include proper scaffolding, edge protection, safe access and appropriate equipment. Anyone carrying out this work should have suitable working at height training.

What It Costs, and What It Returns

Conversion costs depend on the property’s size, condition and location. Typical working figures include:

• Measured survey and drawings: £500 to £2,500.
• Planning and consultant fees: £600 to £3,000.
• HMO licence: £500 to £1,500 or more.
• Fire safety work: £4,000 to £10,000.
• Rewire: £4,000 to £8,000.
• Kitchen upgrade: £6,000 to £15,000.
• Each en-suite: £5,000 to £9,000.
• Loft conversion: £35,000 to £75,000.

A fairly simple conversion might cost £30,000 to £60,000. Adding a loft conversion or several en-suites could push the total towards £80,000 to £120,000.

Ongoing costs include finance, utilities, maintenance, insurance, management and void periods.

For example, five rooms rented at £600 each produce £36,000 a year in gross rent. After bills, management, maintenance, voids and compliance, net income can be much lower.

Always compare the extra net income with the full conversion cost before deciding whether the project is worthwhile financially over the longer term for you.

Before committing, allow for delays and unexpected costs as well. Planning decisions, contractor availability and hidden defects can all affect the final budget. Keep a sensible contingency and make sure your finance can cover a longer project than expected. This gives you more flexibility if work takes longer or costs rise.

When Selling Beats Converting

Converting to an HMO is not always the best option. Selling may make more sense if:

• Planning blocks it: Article 4 restrictions or other planning rules may prevent conversion.
• The layout does not work: Bedrooms may be too small, or adding suitable bathrooms may be difficult.
• The numbers do not work: Conversion costs may be too high compared with the extra income.
• Major repairs come first: Roof, damp or electrical problems can use much of your budget.
• You need certainty: Probate, ownership changes or a need for capital may make a long conversion unsuitable.
• You do not want the management: More tenants normally mean more administration and maintenance.

Properties needing major work can be difficult to sell because buyers may struggle to obtain mortgages.

Some owners therefore choose to sell the house as it stands to a cash buyer. This usually means accepting less than open-market value for greater speed and certainty.

Compare the options carefully. Look at an estate agent’s valuation, any cash offer and the full cost and likely net return of converting.

The Bottom Line

An HMO can increase rental income, but it is not simply a way to charge more rent. You are taking on extra licensing, safety and management responsibilities.

Check planning and Article 4 restrictions first. Confirm room sizes before construction. Understand licensing and fire safety requirements, then calculate your return using net income rather than gross rent.

If the figures show that an HMO performs better than a normal rental or sale, conversion may be worthwhile. If they do not, selling can be an equally sensible financial decision.

*This is a collaborative post. For further information please refer to my disclosure page.