Supporting Act: Exposed Wood Trusses in Design
What's under a pitched roof? Beautiful beams, triangular shapes and rhythm of form
In single-family houses, gable or pitched-roof forms are fairly common. They serve to shed snow and water, and have been carried down over centuries, rooting them in a particular locale. Yet the space under the sloping roofs is often relegated to attic space, tucked above a ceiling. Take away that ceiling, and the structural role it plays in stabilizing a building's roofs and walls, and a grand space is created, one in need of substantial structural members to resist lateral forces (wind) and transfer vertical loads (snow, the roof itself) to the walls or columns. Enter trusses.
When we think of exposed wood trusses — those structural members made up of multiple timbers in triangular configurations, often holding up pitched roofs — rustic spaces come to mind. But open spaces incorporating wood trusses need not recall ski chalets or old barns. Even modern/contemporary architecture, whose flat roofs tend to deter these types of structural members, can embrace them. The following examples merge exposed wood trusses with clean and simple surfaces, creating modern and contemporary spaces.
When we think of exposed wood trusses — those structural members made up of multiple timbers in triangular configurations, often holding up pitched roofs — rustic spaces come to mind. But open spaces incorporating wood trusses need not recall ski chalets or old barns. Even modern/contemporary architecture, whose flat roofs tend to deter these types of structural members, can embrace them. The following examples merge exposed wood trusses with clean and simple surfaces, creating modern and contemporary spaces.
One way of giving exposed wood trusses a modern flavor is to treat them in the same manner as the rest of the construction. This Lake House on Long Island gives every surface — walls, floor, ceiling, trusses — a consistent whitewash. With this treatment, the large living space recalls a gallery, where objects stand out from the white background.
Seen 90 degrees from the previous photo, the trusses in the Lake House give the living space a rhythm that helps break down the scale of the space. And in this photo we see the main justification for the (lack of a) color palette: the view outside becomes an expansive painting of sorts, the colors heightened by the white surfaces.
The antithesis of the previous example may be this Hillside House, where the wood beams are left in a natural appearance. This approach lends this space a warmth, but the treatment of the structure, the walls, and the windows has a simplicity that is still modern.
It should be noted that the roof structure is not technically made up of trusses; they are rafters resting on beams at the bottom and meeting at a ridge beam above. The horizontal members in the center of the photo tie the two sides together for lateral support, where the rafters are doubled up, creating a nice rhythm.
It should be noted that the roof structure is not technically made up of trusses; they are rafters resting on beams at the bottom and meeting at a ridge beam above. The horizontal members in the center of the photo tie the two sides together for lateral support, where the rafters are doubled up, creating a nice rhythm.
The space in the previous photo can seen behind the glass in the top-right corner. In the foreground we see a variation on dealing with the roof structure: intermediate beams helps stabilize the roof structure in concert with the walls on either side of the open space. It's evident in this view that the Hillside House uses wood for just about everything, yet always in a pared-down way that makes the design quite modern.
This grand space also keeps lets the wood's natural appearance prevail. Lots of glass means lots of light and views, be it down low, in a clerestory (barely visible in the top left), or the accent window below the roof's high point. Note that the trusses are built as hybrids, with a steel tension rod taking the place of the bottom chord in the middle.
Here we have another interior that covers most surfaces with wood, but the form is not as straightforward as the previous examples. The trusses below the roof bend down in the background and merge into an angled wall; in the foreground the line of the roof continues behind us, and angled columns break down the interior space. Note the turned-down roofing visible through the triangular window in the top-middle of the photo. This is a dynamic series of spaces, no doubt formed and made explicit by the exposed wood structure.
Of course, one can selectively expose trusses, as in this barn conversion in Texas. The trusses are left open below the light monitor that runs the length of the large double-height space with mezzanine, but they are covered with plaster down below. One speculation on this is to hide mechanical and other services (ducts) behind the ceiling.
In this example, we can see a light monitor in the top-right corner, similar to the previous photo, but here the architect left the wood exposed and treated the lower portion with simple white walls.
And you might be asking, "are all trusses pitched?" Well, as this example attest, the answer is clearly "no." (To go into even more detail, technically all trusses are pitched at least a 1/4" per foot to allow for drainage on flat roofs.) Ironically these flat-roof trusses, gray with prominent grain, are more rustic than the previous examples.
Another view shows the strong rhythm and directionality of a row of trusses.
And still yet another view shows the way a space can be informed by the structure. Here the two walls with storage behind doors follow the rhythm of the trusses above.
A few atypical examples finish this ideabook. Here is a pergola adjacent to a pool, where wood slats comprise the sun shade over the structure. Note how the wood members criss-cross in the bottom-right corner, giving a kinked shape to the roof.
This quirky carport features wood (at least I think they're wood) trusses cantilevered from a freestanding wood-stud wall. Above the trusses is a roof of translucent corrugated plastic. The articulation of the trusses creates an implied ceiling at the bottom chords, making this outdoor space appear rectangular: a box for a car.
This postmodern design shows a series of trusses painted green, easily standing out from the white surfaces. Here the trusses appear more as graphic devices than actual structures, as their spacing seems too far apart, and the triangulation is missing that all-too-important vertical from the apex to the bottom chord. Nevertheless the impact of the trusses on the space is undeniable.
Next: More inspiring architectural details
Next: More inspiring architectural details