HMO Conversions Hounslow

Turning a family house in Hounslow into a small HMO needs planning permission almost everywhere in the borough. The borough-wide Article 4 Direction removing the right to change a dwellinghouse to a small HMO came into force on 4 September 2023, and additional licensing has covered the whole borough since 11 December 2025. So a landlord creating a new shared house works to a planning consent and a licence, and one upgrading an existing HMO works to the licence. We build the rooms, kitchens, bathrooms and fire protection those two documents require.

In Hounslow, a light HMO conversion for four to six tenants typically costs £40,000 to £75,000 in construction, or £90,000 to £150,000 with an en-suite to every bedroom (indicative London ranges, Mayfair Studio and LetCompliance, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Hounslow: we build the fire doors, detection, bathrooms and kitchens to the council's HMO standards, the landlord applies for the licence, and a registered electrician certifies the electrics.

Planning a Hounslow HMO under the borough-wide Article 4 Direction

Elsewhere a house can often become a small HMO without planning permission, but not in Hounslow's residential streets. Under Class L, the 2015 General Permitted Development Order normally lets a C3 dwellinghouse become a C4 HMO. Hounslow's borough-wide Article 4 Direction, confirmed on 8 August 2023 and in force from 4 September 2023, removes that right. It excludes only open land, industrial areas, Chiswick Business Park, Bedfont Lakes Business Park and the Mogden Sewage Works.

If the building is listed, the works themselves are a separate question: anything that affects its character, inside or out, needs listed building consent from Hounslow Council, and carrying it out without consent is a criminal offence.

Size changes the route again. Under the London Plan glossary an HMO housing three to six people falls in Use Class C4, while one housing more than six is sui generis and needs planning permission. Where an HMO needs permission, Hounslow's HMO SPD looks for PTAL 4 or better and town centre facilities no more than a 400m walk away. Your agent tests the house against those before a layout is drawn, and we price from the approved room plan.

Housing in Hounslow

Hounslow's housing, as the Council Tax list records it, is about 111,270 homes: 50% houses, 50% flats, with 16% pre-1919, 28% interwar and 55% built since 1945.

Mandatory and additional HMO licensing in Hounslow

Since 11 December 2025 an HMO in Hounslow with three or more people in two or more households needs a licence of one kind or another. Mandatory licensing applies when five or more people in two or more households share facilities such as a kitchen, bathroom or toilet. The additional licensing scheme catches any section 254 HMO where at least three people from two or more households live. It was designated on 11 September 2025 and ceases on 10 December 2030 unless revoked or extended.

One exception matters here: a flat in a purpose-built block of three or more self-contained flats falls outside mandatory licensing, although a council's additional scheme can still cover it.

The licence application is the landlord's, and the licence sets the building standard. Licences in Hounslow normally run for five years, and where management or condition raises concerns Hounslow normally grants just one year. Letting an HMO without the licence it needs can bring an unlimited fine, according to GOV.UK. That makes the order of work simple: agree the room schedule and amenity plan the licence will be based on, then build to it.

Room sizes, ceilings and bathrooms in a Hounslow HMO

Room sizes in a licensed Hounslow HMO are not negotiable. Hounslow's HMO standards leave no discretion in a licensed HMO: the national minimum standards apply in full: 6.51 square metres for one adult, 10.22 for two, and no sleeping room under 4.64 square metres. The borough adds its own rules. Each room needs a floor to ceiling height of at least 2.14m over 75% of its floor area, and a room may sleep two people at most, whatever their age. A layout that misses either rule has to be redrawn before it is built.

Those numbers are where layouts fail. Attic rooms and rooms under a lowered ceiling are measured against the height rule, and a box room may be usable only as a study or store. Bathrooms carry a rule of their own: Hounslow wants a mechanical extract fan in any bathroom newly provided, even one with a window that opens. We measure every room during the survey, so the licence room schedule, the drawings and the finished house match.

Fire safety, sound and energy in a Hounslow shared house

Fire protection is a large part of the building work in a Hounslow HMO conversion. The escape route, usually the hall and stair, is protected with fire-resisting doors on self-closers to each room and to the kitchen, a mains-powered interlinked detection and alarm system, and fire stopping where services pass through walls and floors. The LACORS guidance on housing fire safety is the recognised reference, Part B applies to the building work, and the licence conditions set the standard the house is held to.

Shared houses are noisy and costly to run, so sound and energy belong in the specification. Resilient bars and acoustic quilt in ceilings between bedrooms and the rooms below cut disturbance and complaints. Insulation, efficient heating and controls help the landlord meet the MEES rules and keep the bills, which are often included in rent, under control. The London Plan says HMOs of a reasonable standard should generally be protected, which is one more reason to build a Hounslow HMO to a good standard.

• Shared kitchens enlarged or added for the number of occupants
• Hot water sized for several sharers showering at once, with any gas work by a Gas Safe registered engineer
• Small HMO conversions for three to six sharers

VOA Council Tax stock of properties, March 2025, for all 29 statistical areas in Hounslow. Counts rounded by the VOA.

Alongside hmo conversions in Hounslow, the pages that usually help next are bathroom renovation in Hounslow, our Hounslow area guide, bathroom fitting in London, what a snagging list covers, how we handle hmo conversions across London and Renovation Budget & Contingency.

Working With GS Renovation in Hounslow

An HMO conversion is built to a document, the licence, and inspected against it. We work from the approved room schedule, fit out kitchens and bathrooms to the amenity plan, and build the fire doors, alarms and fire stopping in the right order so nothing is opened up after inspection. A registered electrician installs and certifies the alarm circuits and wiring, and an engineer on the Gas Safe Register handles gas. You get the certificates the licence application and renewals ask for.

• Sound lining between bedrooms so one sharer does not keep another awake
• Detection laid out to the grade the council's HMO fire guidance sets
• Registered in England, Companies House no. 14611254

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254).