Question:
I own a Dutch Colonial built in the 1920s, and am planning a two-story addition that will include a first floor library and an expanded master bedroom suite above. The lot size and setback rules necessitate a side additionso the view from the street will be affected.  What are some architectural considerations that assure my house retains its curb appeal?  E.W. Fairfax, VA

Answer:
First, its important to know something about this styles history. Dutch Colonials (1890-1930) are a sub-group of the Colonial Revival style (18801955), which is the single most popular architectural style in the United States. The word Revival reflects a late -19th century preoccupation with early American English and Dutch design, an affection for ancestry that began to generally influence the housing landscape in the period after the World War I. Hence, this style has been revisited by popular culture many times, and retains its value because there is agreement over what elements must be retained, and where there is  license to personalize.  

The hallmark of the language, though, is its practicality. Dutch settlers, in fact, often built homes out of the very bricks they had used as ballast in their voyage over from Europe. Remnants of these one-story structures, built as early as 1625, are still found in parts of New York.

The universally distinguishing feature of your home is not its siding material, however, but its roof: specifically, its signature gambrel roof. Sometimes called a Dutch roof or barn roof, the design forms a pentagonal gable defined by of a pair of comparatively flat slopes descending from either side of the center ridge and fanning out into a pair of lower steeper slopes. Some historians say Dutch Colonial is derived from the Flemish farmhouse. In event, by the mid-18th century, the gambrel roof was commonly employed in all sorts of non-Dutch settings.

The reason, again, was practicality. Homebuilders had discovered that Dutch Colonial homes were economical to build since an entire second floor of functional rooms could be contained under the generously spacious gambrel shapeeliminating the need for a full two story elevation topped by an attic. Enthusiasm for this advantage, in turn, fueled the styles broader acceptance; eventually even Sears Roebuck offered a Dutch Colonial-style kit house.

Elaborating a Dutch Colonial Addition
With a front-facing addition it is critical to avoid excessive massing. Architecture is about scale and proportionality, so an addition that doesnt respect the pleasure an eye derives from the measured variance can quickly devolve into a kind of faceless monolith.

On this point, I recommend that you allow the existing house to remain the dominant visual form (mass) and establish the addition, or wing, as subordinate. This can be done by dropping the roof line over the addition and stepping back its front elevation from the main house. This design tactic draws respectful attention to original house and should present aesthetically pleasing proportions. Its all about good manners.

Here are some other key considerations:

Roof: Your addition must employ a gambrel roof that follows the pitch of your existing roof form. Matching the roof shape goes a long way toward blending the new and old. If you want more usable space on the second floor you can increase room size with shed dormers, a well-established style variant. A shed dormers roof is an extension of the upper main roof.

Cladding: A home clad in clapboard, stucco or cedar shingles should generally replicate those materials on the addition. If the main block of your original home is brick or stone, however, I recommend an addition clad in a more humble contrasting material such as wood or stucco, since it reinforces the dominance of the main block. Also, varying the exterior cladding material on your addition adds visual interest.

Doors and Windows: Do replicate the window and door trim of the original house. If your house has wood siding the trim should be in a wide, flat casing. Keep the new window pattern consistent with the existing house; typically double hung windows with 6 lites over 6 lites work well. Because you are building a first floor library you may want to maximize incoming natural light by using a 9 lite over 9 or 12 lite over 12 double-hung window style.

Occasionally the design of the addition can accommodate a few smaller-scale rectangular, oval or round casement windows. However, conservative choices are wise with a front-facing addition.

Summary: Consistency with proportion, materials, window and door style will ensure that your library addition adds curb appeal. Careful planning for your design will add value to your home financially and emotionally. If your home is within a designated historic district study the recommended guidelines.

Bruce Wentworth, AIA, is the principal of Wentworth, Inc. a metro area residential architecture, construction and interior design practice. Questions on residential remodeling and architectural styles can be sent to www.wentworthstudio.com  or call 240-395-0705