Loft, garage or basement: which conversion is right for you?

When you need more room but do not want to lose garden, converting existing space is usually the better move. Loft, garage and basement each suit a different situation, and the right answer depends far more on your building than on your budget.

Loft conversions are usually the best value and add a bedroom or study without changing the footprint. Many fall under permitted development, though dormers and roof changes have limits, and you will need enough head height, roughly 2.2 metres at the ridge.

Garage conversions are quick and cost-effective when the garage is no longer used for a car. They work well for a home office or playroom, and the main considerations are insulation, damp and drainage, all of which the drawings need to address.

Basement conversions add the most space in tight urban plots but are the most involved, with structural, waterproofing and often full planning requirements. The drawing set is correspondingly more detailed.

Whichever route you choose, a Building Regulations set is essential alongside any planning drawings. We confirm the route, prepare the drawings, and guide you through both approvals.

Head height, and what eats it

Measure from the top of the existing ceiling joists to the underside of the ridge. Around 2.2m is the practical benchmark, but insulation and the new floor build-up can take 200 to 300mm before you begin, so 2.4m gives you comfort rather than a compromise.

Trussed roofs need structural work before any usable space appears
Water tanks and old chimney breasts often have to move
Dormers and hip-to-gable changes buy height where the ridge is tight
Rooflight conversions are cheapest but need the most existing height

The staircase problem nobody mentions

Stairs are where loft budgets break. You need 2m of headroom over the flight, relaxed to 1.9m at the centre and 1.8m at the edge on a sloped ceiling, with a maximum pitch of 42 degrees. Finding that space usually means taking a slice from the room below, which is a design decision worth making on paper before anyone is quoting.

Garages and basements compared

A garage conversion is the quickest win: no planning in most cases, but damp, insulation, floor levels and ventilation all have to satisfy Building Regulations. A basement is the opposite, the most space for the most work, with structural design, waterproofing and often a full application.

What approvals you will need

Building Regulations apply to every conversion without exception, because you are creating habitable space with new structure, fire escape and insulation requirements. Planning permission is a separate question that depends on the roof shape, the property type and the location.

Where we come in

We confirm which route applies to your property in writing, prepare the drawings, and handle the application with the council. See loft, garage and basement drawings, or get your drawings quoted with no obligation. If any application we submit is refused, you get a 100% refund within 5 days.