DORMER LOFT

What is a dormer loft conversion?

A dormer loft conversion is when a pitched roof is converted into a box shaped structure, creating walls that sit at a 90 degree angle to the floor. This helps increase space in your loft making it more easily liveable.

A dormer loft conversion is an extension structure which is built to protrude from the existing sloping roof to create more usable space with additional headroom, meaning that a cramped loft can become a larger, airy room with the new dormer windows providing transformative natural light. There are several different types of dormer loft conversion and the one most suited to your property will depend on your type of house (terraced, semi-detached, detached) and your existing roof shape. 

The flat roof dormer loft conversion is a simple structure that can be added to the front and/or rear of the loft. It provides a fairly simple way to expand the usable space in the loft, increasing head height and providing lots of natural light afforded by the dormer windows.

The shed roof dormer loft conversion is similar to the flat roof option but its roof slopes down at an angle slightly, may be constructed with different materials and is usually more suited to homes with a gable roof.

The gable fronted dormer loft conversion, which is sometimes also known as a dog-house dormer is a more complex solution consisting of a gable wall extension which is built upwards to meet the current ridge line, with a new sloping roof section also built towards the new gable end.

A hipped roof dormer loft conversion is an extension where the roofs slope on all three sides of the structure, often an aesthetically pleasing look especially suited to properties in some styles, but this type of dormer construction results in less usable space in the new loft than for example, a flat roof dormer.

Some types of dormer loft conversions can result in up to 50 cubic metres of additional space, depending on the type of house and the size and style of the extension. In addition, much of the work involved can be carried out from scaffolding outside your home, making for minimal disruption when compared to most other types of home extension.

What should the ceiling height for a dormer loft conversion be?

When determining if your loft is suitable for a loft conversion you need to think about ceiling heights. A traditional roof is 2.2 to 2.4 meters high and the minimum height for a modern trussed roof is 2.4 to 2.6 meters. The preferred level of headroom for a habitable space is 2.3 meters. This height does not need to be maintained over the whole flooring area and a lower height may be acceptable for a bathroom, corridor or kitchen.  If your head height is lower than the above, it may be possible to achieve this by lowering the ceilings of the floor underneath.

Exterior cladding for a dormer loft conversion

When planning a dormer loft conversion it is not just what’s on the inside that counts. What you clad your dormer in matters too. Depending on where you live in London, especially if you live in a heritage or conservation area, you may have to clad your dormer in a certain material. If you have the freedom to choose, options include:

• Slate style tiles – these tend to match the roof tiles.
• Rendering – this can only be done if the dormer is made of block walls rather than timber frames.
• Glass Reinforced plastic – a hard wearing material which should last 20 years.
• Timber – there is an array of options.
• Metal cladding – there are various styles to choose from but zinc or copper are the most popular.