A garage conversion involves transforming an existing garage into usable living space. That might be a home office, a spare bedroom, a gym, a playroom, or an annexe for a family member. Because the structure already exists, garage conversions typically offer more space per pound than an extension. You’re not building from scratch, just adapting what’s already there.

That said, adapting still involves real work: insulation, flooring, windows, electrics, plumbing (if you need a bathroom), and getting everything up to building regulation standards.

Not all garages are the same, and the type you have makes a significant difference to cost.

Integral garage conversion: This is the most common type. An integral garage is built into the footprint of the house, usually beneath a bedroom. Because it shares walls and sometimes a roof with the main property, it tends to be cheaper and less disruptive to convert.

Attached or semi-detached garage: This sits alongside the house but isn’t built into it. It shares at least one wall with the main property. Conversions here are slightly more involved than integral, mainly because of insulation requirements and the need to create a proper connection into the house.

Detached garage conversion: A fully detached structure in the garden. These take the most work to convert because they need their own insulation on all sides, and running power, water, and heating from the main house involves more complex groundwork. Detached conversions can be excellent for studio space, home offices, or self-contained annexes.

Double garage conversion: Whether integral, attached, or detached, converting a double garage doubles your usable square footage. Many people choose to convert half and keep the other half as storage or parking.

In most cases, converting a garage to living space falls under permitted development, which means you don’t need planning permission. However, there are exceptions: if your property is in a conservation area or is listed; if permitted development rights have been removed by the local authority; if you’re creating a completely self-contained dwelling; or on some newer estates where the original planning approval required parking to be maintained.

Even if planning permission isn’t needed, building regulations approval always is. A garage conversion must meet current standards for insulation, ventilation, electrics, fire safety, and structural stability.

Generally, yes. Adding a habitable room to a property tends to improve its market value, and estate agents consistently report that converted garages are viewed positively by buyers, especially when done to a good standard and properly signed off with building regulations completion certificates.

The key caveat is parking. If you’re in an area where off-street parking is scarce, buyers may not be as enthusiastic about losing a garage space.