HMO Conversions Windsor

An HMO conversion in Windsor adapts a house to be let room by room to unrelated sharers, or upgrades an existing shared house to meet its licence. The Royal Borough treats a house as an HMO once three or more people who are not one household live there, and requires a licence where five or more people in two or more households share a facility. We build the fire protection, kitchens, bathrooms and room layouts to those standards, and the landlord applies for the licence.

For Windsor, 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 (Mayfair Studio and LetCompliance, 2026); a Berkshire price follows a site visit. GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Windsor: 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 for a shared house in Windsor, small or large

Planning turns on how many people will live in the house. Under national rules, a change from a family house (C3) to a small HMO for three to six unrelated people (C4) is permitted development unless a local direction removes that right. The landlord or their agent confirms with the Royal Borough of Windsor and Maidenhead whether any direction covers the street. An HMO for seven or more occupants is sui generis and always needs planning permission. The Royal Borough is the planning authority for the whole of Windsor, across the SL4 postcode district.

The house matters as much as the use class. Across the statistical areas covering Windsor and Eton, houses make up 66% of homes, and 32% of all homes are semi-detached or detached. A larger semi or detached house with several good bedrooms and space for a second bathroom converts more easily than a narrow terrace, because the sharers need kitchen and washing facilities in proportion to their number. On the Laing Estate, the deeds of individual houses carry covenants intended to keep the original design, so a landlord checks them before planning new windows or an extension for an extra room.

Housing in Windsor

Around 16,960 homes make up Windsor on the valuation list; 34% are flats and 66% houses, and 22% date from before 1919, 8% from between the wars and 68% from after 1945.

The Royal Borough HMO licence and the plan a Windsor house needs

Licensing is separate from planning. The Royal Borough requires an HMO licence where the house is occupied by five or more persons in two or more households who share one or more facility, such as a kitchen or bathroom. The landlord applies, and the fee rises for each bedroom beyond five, so the bedroom count is a cost decision as well as a rental one. An application must include a plan showing the layout of each room with room sizes and facilities, which means the finished layout has to be measured rather than estimated.

We build to the layout that plan will show. Before work starts in Windsor, the landlord's designer fixes the room sizes, the number of kitchens and bathrooms and the escape route, and we check them against the house on site. At handover we provide measured as-built floor plans with room sizes, so the plan the landlord submits matches the building. The Royal Borough says it makes proactive unannounced visits and responds to complaints to check HMOs are safe, and a house that matches its licence plan stands up to that scrutiny.

Amenities, bedroom sizes and electrics in a Windsor HMO

The Royal Borough checks HMOs for amenities, meaning kitchens, bathrooms, toilets and wash hand basins, and for overcrowding by the number and size of rooms. The number of sharers therefore sets how many cookers, sinks, WCs and showers the house needs, and adding one bedroom can trigger another bathroom. National mandatory licence conditions, measured on usable floor area, also set 6.51 square metres for one adult and 10.22 for two, and no room under 4.64 square metres may be used for sleeping. In a Windsor house we measure every room at survey, because a bedroom that falls just short changes the whole scheme.

Mandatory licensing does not reach a flat in a purpose-built block of three or more self-contained flats; where such a flat is shared, it is the council's additional scheme, if any, that applies.

Electrics carry an ongoing duty. The Royal Borough's HMO management summary requires every fixed electrical installation to be inspected and tested at least every five years. We lay out circuits so each floor or group of rooms can be isolated, place a lockable consumer unit where the landlord can reach it, and provide the circuit schedule the next inspector will need. A registered electrician certifies the installation at handover, and the landlord books each five yearly test from there, keeping the reports for the licence file.

Fire safety, sound and energy in a Windsor shared house

Fire safety is the core of an HMO conversion. The recognised guide is the LACORS housing fire safety guidance, applied alongside Part B of the building regulations, and it sets the level of protection by layout and number of storeys. A conversion commonly needs fire doors with self-closers to every bedroom and the kitchen, an interlinked mains-wired detection and alarm system, and a protected route to the front door. The common parts fall under the Fire Safety Order, so the work needs full plans rather than a building notice. We agree the specification with the landlord's designer before stripping out.

Sound and energy come next. Bedrooms let to separate people share walls and floors, so we insulate between lettings with mineral wool in stud walls and acoustic layers in the floors. Where the let needs an EPC, which is not always the case for a house let room by room, the Minimum Energy Efficiency Standards require band E or better, for existing tenancies as well as new ones, unless an exemption is registered. Either way, an HMO conversion in Windsor is the time to insulate the loft, upgrade the heating and fit room controls. Noisy work follows the Royal Borough's recommended hours for building work, which keeps the neighbours on side during the build.

• Shared kitchens enlarged or added for the number of occupants
• Protected escape routes through the hall, stair and landings
• Bedroom layouts checked against the national minimum room sizes

VOA Council Tax stock of properties, March 2025, for all 5 statistical areas in Windsor. Counts rounded by the VOA.

Once the hmo conversions work in Windsor is scoped, people usually go on to read bathroom renovation in Windsor, hmo conversions in Slough, how building control works in London, how snagging works at handover, hmo conversions across London and Getting Planning Permission.

Working With GS Renovation in Windsor

An HMO is inspected for years after the builders leave, so it has to be built right the first time. We survey the house in Windsor, check the proposed room sizes and escape route on site, and run the conversion in a fixed order: strip out, fire separation and new bathrooms, services, then doors, alarms and finishes. The landlord applies for planning and the licence, and as a landlord converting to let is a commercial client with duties of its own under the CDM Regulations. We build to the approved layout and hand over measured plans, certificates from a registered electrician and records of gas work by an engineer on the Gas Safe Register.

• Sound lining between bedrooms so one sharer does not keep another awake
• A written scope and programme agreed before work starts
• Kitchens and bathrooms counted against the council's amenity standard

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