How to Design Dormers

Consider what the use of the dormer will be. Dormers are ideal for home offices, playrooms, sitting areas, bathrooms and additional living areas.

Consider the existing home design. The exterior roof area of your home already has a distinctive style, and dormer conversions or dormer windows should integrate harmoniously with the material type, style, sills, windows and color of the exterior.

Maintain the appropriate architectural style of the home. To best suit a cottage or unadorned home style, simple shed dormers are appropriate. To best suit a traditional or colonial home style, a gable end dormer will best complement the formality of this design.

Find out whether permission is required for this home addition. Check your local regulations to be sure the roof space is not being extended beyond the specified conditions and limits. Check whether other permits or requirements are needed.

Keep the dormer size-proportionate to the size of the house structure. Large dormers on a small house will tower over the house and look awkward. Sketch the dormer into the roof line and find out where the support beams are placed in the attic to understand how the home's roof is supported.

Ensure the window covers at least 75 percent of the dormer’s face in your design, if the dormer is a window dormer. Designing a window dormer with too much siding or stucco will make it appear heavier than it is. Depending on the side of the dormer, you can include more than one window in the design.

Design two dormers to create balance. Most homes require two dormers to provide balance for the overall design and structure stability.