Building Envelope: Ceilings and Roofs

In this post, we'll explore how patterns influenced our building envelope, focusing primarily on ceilings and the roof. (As before, problem descriptions and solutions — the first two bullet points of each section — are from A Pattern Language.)

Sheltering roof (117):

• Problem: The roof plays a primal role in our lives. The most primitive buildings are nothing but a roof. If the roof is hidden, if its presence cannot be felt around the building or if it cannot be used, then people will lack a fundamental sense of shelter.
• Therefore: Slope the roof or make a vault of it, make its entire surface visible, and bring the eaves of the roof down low, as low as 6'0" or 6'6" at places like the entrance, where people pause. Build the top story of each wing right into the roof, so that the roof does not only cover it, but actually surrounds it.
• In our home: It would be an understatement to say that modern-styling does not lend themselves to this pattern. So we asked ourselves, "What is the essence of this pattern?"
  
  Patterns of Home, a modernized look at some of the home oriented patterns in A Pattern Language, gives a clue. The roof should, above all, provide a sense of shelter. It should provide a sense of connection between the inside and the outside. A Pattern Language focuses on achieving this via living space within the roof, but another way to achieve this is to have the same roof surface expressed inside and out.
  
  Our home has two roof lines — the top and a midline. Both are true roof surfaces in that they cover interior space that is not covered by the other. Both roof lines are expressed inside and outside the house. The lower roof line defines both an exterior midline and the maximum ceiling height on the main floor. The butterfly shape of the upper roof is also expressed inside; most of the rooms upstairs have a slanted roof that continues the external expression of the butterfly roof.
  
  Equally important is the sense of indoor/outdoor transition that our roof gives at two key locations, both shown below. The picture on the lower left shows how the roof itself provides protection over our upstairs deck. The picture on the lower right shows the same sense of protection over the main entry (and as the top picture shows, the sense of that protection being part of the roof is even greater now that the roof trim has been installed).
  
  In retrospect, I would have tweaked the roof design a bit to give it a greater sense of shelter, even within the confines of a butterfly roof. The mid-line roof does not shelter the main floor deck as effectively as it does the entry, and it does not continue on the north side or fully around the west side. Not continuing the middle roof line all the way around weakened the sense of the roof really being part of the home. However, from the east and south sides, we did pretty well considering the inherent limitations of the style we had settled on.

Ceiling height variety (190):

• Problem: A building in which the ceiling heights are all the same is virtually incapable of making people feel comfortable.
• Therefore: Vary the ceiling heights continuously throughout the building, especially between rooms which open into each other, so that the relative intimacy of different spaces can be felt. In particular, make ceilings high in rooms which are public or meant for large gatherings (10 to 12 feet), lower in rooms for smaller gatherings (7 to 9 feet), and very low in rooms or alcoves for one or two people (6 to 7 feet).
• In our home: I would say that we achieved the minimum viable amount of ceiling height variety needed to say that we have variety. Much to my sadness, we don't have any nooks or alcoves which take advantage of a lowered ceiling to make them feel cozier. However, we do do use ceiling height to provide social cues and, on occasion, to give a sense of grandeur.
  
  The main floor has 10' ceilings. This is high, but anything lower would feel low in this broad, open space. To keep this area from feeling cavernous and undifferentiated, we vary the ceiling height. The entry is raised above the main floor. This gives a sense of compression and expansion that emphasizes the height of the main living area. The area over the kitchen is soffited down to differentiate that space from the dining area adjacent to it (the diagram below shows the kitchen soffit, but that only goes part way across the ceiling). The living room has a support beam which provides a natural gateway separating that space.
  
  
  
  The bedrooms have a lower 8' ceiling height to match their more intimate scale. To give a sense of the roof from the inside, all of the bedrooms have a ceiling line which follows the butterfly roof. This, along with window placement, gives a feeling of opening the rooms to the view outside.
  
  
  
  The most dramatic use of ceiling height variety is in our stair tower. The stair tower stretches the whole height of the building, and the open tread stairs really allow you to get a sense of the height of the structure. The picture below, which shows the upper 1.5 stories of the stair tower, gives a feel for the sense of height it brings to our home.

The next post will cover openings in the building envelope for windows and doors.