What's A Dormer Addition?

A dormer addition is a structural expansion of a building that protrudes from an existing sloping roof. Dormers can either be part of the original construction, or added later. They create usable space in the roof of a building by adding headroom and windows.

Like skylights, windows in a dormer addition are a source of light and ventilation. But unlike skylights, they also increase the amount of usable space in what used to be attic storage. Dormers are typically one of the primary elements of a loft conversion.

There are such things as "blind dormers." These can only be seen from the outside, since they are roofed off on the inside, and don't provide any extra space or light. They are usually designed into large homes, to make them appear more impressive from the street.

There are several types of dormers. The most common is the "Gable Fronted Dormer," where the front of the dormer rises to a point at the ridge of the dormer's roof. This is also knows as a "dog house" dormer. See the picture below.

Then there's the "Shed dormer." See the picture at left. Often used in gable-roofed homes, a shed dormer has a single-planed roof, pitched at a shallower angle than the main roof.

You can have a "Hipped Roof Dormer" where the roof slopes back from the front of the structure to a point farther back.

A "Flat Roof Dormer" is self-explanatory. It has a flat roof.

And then there's the "Wall Dormer", whose face is the face of the wall below. See the last picture below.

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