Dormers are often used inattic conversionsto add a window for light and cross-ventilation.

However, these windows also have a few drawbacks.

Dormers enhanceVictorianscrollwork, pediments, and window symmetry in homes with similar detailing.

Red roof with dormer

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Gable dormers were very popular in theCape Cod-stylehome designs of America’s midcentury building boom.

Simple dormers were added to the home’sgable roofto add light, air, space, and symmetry.

They are common in Craftsman-style homes and bungalows.

Cape Cod style house with two dormers on the house and one over the garage door.

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Extended Shed Dormers

An extended shed dormer extends nearly the entire width of a house.

This bang out of dormer adds a substantial amount of interior space without changing the footprint of the home.

This dormer pop in frequently emerged in the 1960s and remains a popular architectural style.

Craftsman home with dormer

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Here, a postmodern architect added this traditional architectural detailing but with a twist.

These eyebrow dormer windows seem to make this home come alive.

French architect Francois Mansart (15981666) modified the gambrel roof by making the sides steeper and inserting windows.

mansard roof on victorian house

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Mansard roofs are some of the earliest examples of dormer windows.

Modern buildings with Mansard roofs usually have dormerssometimes wall dormers (through the cornice) and roof dormers.

These “through-the-cornice” dormers serve as a continuation of the wall above the roof eaves.

Typical American home with four-window dormer along the length of the roof facade

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It consists of two gable dormers flanking a flat shed dormer.

Recessed Dormer

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A recessed dormer is set into a roof rather than protruding.

It has a small landing outside the window before the roof line begins again.

Flat roof dormers with vertical panes project from a nontraditional sloped roof of a modern building facade

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This style typically has a deep dormer that allows for more square footage within the dormer.

This punch in of dormer is often used for patio or garden space.

False Dormer

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A false dormer is precisely what it sounds like.

Large Spanish-inspired home, arched windows on the first floor, 6 over 6 windows on the second floor, and a dormer with small vertical windows on the red roof over similar windows on the second floor

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Prefab Dormers

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Another option is to add a prefabricated dormer to an existing home.

Since this key in of dormer involves home modification, it likely requires a plan and a permit.

Depending on your roof’s material and design, the project may be more complex.

view of second floor and roof facade, three-sectioned arched eyebrow windows on a Thatched Roof between two enormous chimneys with chimney pots

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Labor and materials are critical costs to consider.

Dormers were the name for windows used in attic sleeping rooms in French homes.

A gable roof has two sides that form a peak at the top.

Two eyebrow window dormers in a red tile roof

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A dormer can protrude through a gable roof.

You will probably need a permit to add a dormer to your home.

Sometimes the town planning department needs to confirm the dormer doesn’t exceed height restrictions, for example.

Detail of ornate gabled dormer windows from the steep slope of a mansard roof

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A mansard is a French or curbed tiled or shingled roof often paired with dormers.

Dormer and Eyebrow Windows.

In: SiteCarpentry and Advanced Joinery.

House where the dormers split the line of the roof, the bottom of the window is on the siding facade and the top gable protrudes from the roof

J.Castro/Getty Images

Palgrave, London.https://doi.org/10.1007/978-1-349-06901-9_9

Second Empire Mansart Style 1860-1900.Pennsylvania Historical and Museum Commission.

Biltmore House.Society of Architectural Historians Archipedia.

How much does a dormer addition cost?Homeadvisor.

Facade of two-dormer, side chimney, 1-bay garage Cape Cod style home, with multi-paned windows with geometrically-patterned shutters

Ryan McVay / Getty Images

ABCs of Architecture.New Haven Preservation Trust.

Recessed dormer with terracotta roof

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Reverse dormer on a cream home

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False dormers

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A prefab dormer is installed with a crane

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A bedroom inside a dormer.

A Bedroom Inside a DormerPhoto by Image Studios / UpperCut Images / Getty Images