Loft & Garage
Conversions

It depends entirely on type. A velux conversion, where the roof shape does not change, runs 25,000 to 40,000 pounds. A rear dormer is 30,000 to 65,000. Hip to gable is 33,000 to 70,000, a mansard 38,000 to 90,000 and an L shape dormer 55,000 to 100,000. Adding an ensuite is another 6,000 to 12,000 on top.

The rough test is 2.2 metres from the top of the ceiling joist to the underside of the ridge, measured at the highest point. Below that you are usually looking at a mansard or lowering the ceilings below, both of which change the cost significantly. We measure it properly on the first visit rather than guessing from the hatch.

Velux, dormer, hip to gable and L shape conversions are often permitted development, subject to volume limits and where the dormer sits on the roof. Mansards usually need a full application because they change the roof shape so substantially. All of them need building regulations approval regardless, particularly for fire escape and the staircase.

A single garage is typically 7,000 to 18,000 pounds and a double 15,000 to 30,000. Adding a cloakroom is another 2,800 to 4,500, a shower room 5,000 to 8,500, and a kitchenette to make it a self contained annexe 3,500 to 7,000. Most are done in two to five weeks.

Usually not, provided the work is internal and the footprint does not change. Where it gets complicated is if the property has a planning condition requiring the garage to be kept for parking, which happens on some newer estates, or if you are in a conservation area. We check the title and any conditions before quoting.

Garage floors usually sit lower than the house and are rarely insulated or damp proofed. The floor has to be built up with a damp proof membrane and insulation, which eats into head height. If the garage is already low, that is the thing that decides whether it works, and it is the first thing we check.

Yes, and most people do. The bulk of the work happens above your existing ceilings and is reached from scaffold outside. The disruptive part is cutting in the staircase, which is usually a few days near the end.

Turning a two storey house into three storeys triggers fire regulations. In practice that usually means fire doors on the rooms off the stairwell, mains linked smoke alarms and a protected escape route down the stairs. It is not optional and it is not something to let a cheap quote skip, because it is the part that keeps your family safe.