Loft Conversions London: What is a Dormer?

London Loft conversions are an increasingly popular way for homeowners to expand the useable space within their house without going through all of the hassle and expense of moving. There are a number of different types of loft conversions in London but the most common is a 'dormer'. What is a dormer and what are its benefits and disadvantages?

The main objective of anyone considering an attic conversion in London is to achieve more useable space. In some cases the space within the existing loft is sufficient to add a bedroom and bathroom just by installing VELUX windows in the existing slope to provide natural light. In most properties the existing space is too small to be used for much more than a storeroom and so the most common type of work undertaken is the installation of a dormer as the back of the property.

A dormer loft conversion will usually protrude from the rear roof at a ninety degree angle, stepped back at least 200mm from the rear wall of the house. Dormer loft conversions in London significantly add to the useable floor area by extending the height at the existing ridge for the majority of the rear half of the property. They are constructed using an insulated timber frame with marine ply exterior. Most dormer loft conversions include a window or set of French doors, providing natural light and a garden aspect.

London loft conversions incorporating a rear dormer design are generally hung externally in slates or tiles to match the existing roof although can be rendered, clad in timber, lead, aluminium or any other suitable external material. An important consideration when selecting external materials is maintenance of the finish. Most traditional roofing materials do not require regular maintenance however a timber or rendered finish will require regular care which can add to the long-term costs.

Most dormer conversions have a 'flat roof' which is usually a three layer felt roof, although can be lead or a liquid poured roof, depending on the specification required. It is possible to lay a 'green roof' on top of the flat roof which can be a great benefit to wildlife in urban areas and helps to regulate the temperatures in London loft conversions, especially on very hot or cold days.

Some dormers do have a pitched roof (either with a single pitch or a double pitch) which is often more sympathetic to the look of period properties. The disadvantage of a pitched dormer is that it requires more existing head height in the loft as the pitched roof adds to the overall height. It also does not provide as much useable floor space as a standard flat roof dormer. Yet pitched dormers are popular with planning departments as they do not dominate the entire roof. In some cases pitched dormers are the only way to achieve planning consent for a loft conversion in London.

You should always ensure that you seek professional advice from a qualified architect or surveyor before undertaking any work to your property. As when undertaking any building work, you should always make use of a company that is a member of the Government Backed TrustMark Scheme and ensure that you go and look at some of their completed work.