What drives the cost of an HMO conversion?
The cost of an HMO conversion depends mainly on the condition of the house, the number of rooms, how many en-suites you want and what the fire strategy requires. The main drivers are:
- Starting condition. A sound house that needs redecoration and new finishes costs far less per room than one that needs rewiring, replastering and new floors throughout.
- Room count and layout. Moving walls to create rooms that meet the minimum sizes adds structural, plastering and electrical work.
- En-suites and shared facilities. Each en-suite is a small bathroom, and the council's amenity standards set how much kitchen and bathroom provision the house needs.
- Fire safety. The number of fire doors, the alarm system, fire-resisting linings and emergency lighting follow the fire risk assessment and council standards.
- Drainage and services. Bathrooms far from the existing soil stack, or a new kitchen location, add cost.
- Property type. Older houses and commercial conversions often bring more unknowns than a standard terrace.
What are typical HMO conversion costs in the Midlands?
These are our typical Midlands guide ranges for October 2026. They include VAT where it applies, and every figure is confirmed after a survey in a fixed written quote.
| Item | Typical guide range |
|---|---|
| Building work per lettable room: light | £1,800 to £3,500 |
| Building work per lettable room: standard | £5,500 to £9,000 |
| Building work per lettable room: full strip-out | £9,000 to £14,000 |
| En-suite shower room (each) | £4,500 to £7,500 |
| Communal kitchen | £7,000 to £13,000 |
| Extra shared bathroom | £5,000 to £9,000 |
| Fire door, supplied and fitted (each) | £450 to £750 |
| Fire alarm system (per storey) | £700 to £1,600 |
| Loft conversion adding rooms | £38,000 to £60,000 |
Light work suits a house in good condition that mainly needs redecoration, new finishes and minor alterations. Standard work covers the typical conversion with new partitions, electrics, plastering and finishes. Full strip-out applies where the house is taken back to its structure. Use our HMO conversion guide price tool for a range based on your house.
What would a five-room HMO conversion cost?
Here is a worked illustration using the guide ranges above for a two-storey terraced house converted into a five-room HMO. The scope is standard building work to five lettable rooms, two en-suite shower rooms, a new communal kitchen, one extra shared bathroom, seven fire doors and a fire alarm system on both storeys.
| Item | Calculation | Low | High |
|---|---|---|---|
| Standard building work per room | 5 rooms × £5,500 to £9,000 | £27,500 | £45,000 |
| En-suite shower rooms | 2 × £4,500 to £7,500 | £9,000 | £15,000 |
| Communal kitchen | 1 × £7,000 to £13,000 | £7,000 | £13,000 |
| Extra shared bathroom | 1 × £5,000 to £9,000 | £5,000 | £9,000 |
| Fire doors | 7 × £450 to £750 | £3,150 | £5,250 |
| Fire alarm system | 2 storeys × £700 to £1,600 | £1,400 | £3,200 |
| Total | Sum of the rows | £53,050 | £90,450 |
| Rounded to the nearest £500 | £53,000 | £90,500 |
So a five-room standard conversion of this kind would typically fall between about £53,000 and £90,500, including VAT where it applies. The low end assumes a straightforward house with drainage near where the bathrooms go. The high end reflects more alteration, higher-specification fittings and harder access. This is an illustration, not a quote: the number of fire doors and the alarm system depend on the fire risk assessment and the council's standards, and the real figure is fixed after a survey.
What is not included in HMO conversion guide prices?
The guide ranges cover building work. They do not include:
- Council HMO licence fees, which each council sets.
- Planning application fees, where an application is needed.
- Building control fees, charged by local authority building control or a registered building control approver.
- Furniture and white goods for bedrooms and shared areas, unless agreed in the specification.
- Professional fees you may need separately, such as a structural engineer or a party wall surveyor.
- Purchase costs, finance and tax, which are outside our scope. Take regulated advice on these.
Check each council's current fee schedule rather than relying on a figure from a forum. Compliance, management and appraisal services are quoted per property, and management terms are agreed in writing before you instruct us.
How can I keep HMO conversion costs down without failing the licence?
The cheapest conversion is the one you only do once. Ways to control cost without risking the licence:
- Read the council's standards before design. Building a room that turns out to be too small, or a kitchen that is undersized for the occupancy, is the most expensive mistake.
- Keep wet rooms near existing drainage. Stacking en-suites above each other and near the soil stack saves plumbing and drainage work.
- Size the fire strategy to the risk. The LACORS guidance is risk-based. In a lower-risk house of sound construction, it may accept good-quality, close-fitting, self-closing solid doors rather than full replacement. Agree the approach with the council before ordering.
- Be wary of a seventh resident. Seven or more residents makes the house a large HMO, which always needs planning permission.
- Fix the specification before work starts. Changes once work is under way cost more.
- Choose hard-wearing finishes. Fittings that survive frequent changes of occupier cost less over time than cheaper ones that need replacing.
Cutting the fire safety or room size work to save money is a false economy. The council can refuse or restrict a licence, require works, and impose a civil penalty of up to £40,000.
How much does a large HMO or loft conversion cost?
A large HMO with 7 or more residents uses the same per-room and per-item guide ranges, but the overall scope is often bigger. Large HMOs commonly need more kitchen and bathroom provision under council standards and more extensive fire protection, and they always need planning permission, which brings its own fees and drawings.
Adding rooms in the roof space is a typical loft conversion. Our guide range is £38,000 to £60,000, including VAT where it applies, depending on the size, the type of dormer and the work needed to protect the escape route from a new storey. Remember that floor under a ceiling lower than 1.5 m does not count towards a bedroom's size. See our HMO loft conversions and large HMO conversions pages.
How do I get a fixed price for an HMO conversion?
Our process is designed to turn a guide range into a firm figure:
- Use the guide price tool or call us on 0800 088 6341.
- We carry out a free survey. We measure every room and check the council's licensing and planning position for the address.
- We agree the specification with you: room count, en-suites, kitchen and bathroom provision and the fire strategy.
- We give you a fixed written quote for the agreed specification, itemised so you can see where the money goes.
- We agree a programme, then carry out the works, collect the certificates and hand over.
The work is carried out by S&K and vetted subcontractors working under S&K, and you contract with us for the whole job. We reply to enquiries within one working day. See our HMO conversions service for more.
Sources
- Housing Act 2004, Schedule 4: licence conditions
- GOV.UK: Building regulations approval, how to apply
- GOV.UK: Fire safety risk assessment, sleeping accommodation
- Town and Country Planning (Use Classes) Order 1987, Schedule
This guide explains the rules in England as we understood them in October 2026. It is general information, not legal or financial advice. Check with your council and take professional advice for your own situation.