Material Choices: High Marks for Reinforced Concrete
Try poured-in-place construction for a wonderfully tactile, industrial look
The second in my series of ideabooks on industrial materials looks at reinforced concrete, defined as concrete strengthened with steel reinforcing, be it bars or mesh. Concrete is a material that excels in compression, so the addition of steel, which is good in tension, results in monolithic walls or floors with the best of both structural worlds. It also results in a distinctive appearance that is industrial yet very tactile and very diverse in application.
Reinforced concrete is sometimes referred to as poured-in-place concrete, since it necessitates that the formwork, reinforcing, and the actual pouring of the concrete happen on-site. Alternatively, precast concrete and concrete blocks are respectively prefab and modular construction elements made from concrete off-site. The following examples illustrate the first condition, the rootedness in place that results from using reinforced concrete.
Reinforced concrete is sometimes referred to as poured-in-place concrete, since it necessitates that the formwork, reinforcing, and the actual pouring of the concrete happen on-site. Alternatively, precast concrete and concrete blocks are respectively prefab and modular construction elements made from concrete off-site. The following examples illustrate the first condition, the rootedness in place that results from using reinforced concrete.
This is easily the most imposing concrete exterior on Houzz, a residence on Bainbridge Island, Washington by Matthew Coates. This view gives the appearance that the house is entirely made of reinforced concrete, but another look reveals...
...the concrete wall is a screen of sorts, giving privacy and insulation to the wood and copper box behind it. It also acts as a strong transition between the public and the private, a threshold between the two. Behind this concrete wall the house is quite open, with large areas of glass affording water views; the occasional inside face of the concrete wall reminds people of the exterior face.
The exterior walkway to this five-story house on a steep and wooded lot is highlighted by the tall reinforced concrete wall on the left. Directly behind it is the interior stair, which is actually supported by the structural concrete wall.
The exterior is articulated with horizontal lines and a grid of holes, marks of the wall's construction. The first relate to the height of the formwork panels and the extent of the concrete pour for a particular day, while the latter results from the rods used to hold the forms together. For the sake of appearance, they both need to be considered by the architect and contractor.
The exterior is articulated with horizontal lines and a grid of holes, marks of the wall's construction. The first relate to the height of the formwork panels and the extent of the concrete pour for a particular day, while the latter results from the rods used to hold the forms together. For the sake of appearance, they both need to be considered by the architect and contractor.
Exterior applications of reinforced concrete need not be as overwhelming as the previous examples. This mountain home uses concrete walls in a more traditional manner, as a foundation for the timber columns, walls, and roofs above. Yet where concrete foundations usually only peek above the grade surrounding a house, here the material defines the front patio and part of the first floor. A closer look at the steps from the driveway ...
... shows the residue of the wood planks that made up the formwork. The walls and columns have a tactile quality that comes from the horizontal lines, where wet concrete oozed into the gaps between the wood. Topping the wall is a smooth cap with integral numbers for the address, probably metal letters inserted into the reveal.
Compared to the previous photo, these horizontal lines created by the formwork are extreme. It is obvious that the architect intended this result, most likely going so far as designing the forms or giving the contractor criteria for the intended appearance. As a porch addition to a house with horizontal siding, this choice seems appropriate. The plasticity of concrete is apparent in the hollows for firewood in this wall.
The previous few projects showed a couple results from formwork in reinforced concrete construction: panels and holes versus horizontal lines without holes. This house in Seattle, Washington's Queen Anne neighborhood — a renovation of an old brick house with new concrete, glass and steel insertions — shows a synthesis of sorts. This exterior wall is smooth, with a grid of holes that alternate with the form's horizontal bands. This carefully crafted appearance is also visible inside ...
... where it is contrasted with concrete walls that are rougher, darker, and a horizontal stripe at about head height. The latter is found in this family room and other lower level spaces, but in the floors above it gives way to lighter (physically and visually) materials, culminating in dramatic open views of the city's Space Needle.
This project in Venice, California is actually two homes that mirror eachother on side-by-side parcels. Stucco and glass wrap the upper floors, but at grade it is concrete that prevails. In the garage and adjacent multi-purpose room the effect is cool to the touch. The concrete is softened by the landscaping in the central court between the buildings.
This villa uses concrete alongside other materials (wood, stone, steel), but the effect is visually light and cool. The horizontal and vertical lines in the concrete are clearly well thought out here, recalling a museum more than a residence, especially in combination with the color and smoothness of the wall.
As a contrast to the previous photo, these concrete walls are dark and heavy; almost wet in appearance. The intention was much different, as are the spaces, which are more intimate and layered with contrasting materials.
Lest we forget, concrete's appearance is not all light/dark and the articulation of formwork; it can also involve colored pigments. Assuming this photograph is telling the truth, the concrete was mixed with a pigment to give it this blue-gray appearance. The wood grain still found in the concrete, combined with the color, gives the impression that stained wood makes up the wall surface.
Last, this basement wine cellar is found in a house with walls of concrete, stone and wood slats, each with a strong texture. The prevalence of concrete in this lower level makes sense, given the material's structural and insulating properties. The latter make it ideal for helping to create a cool space for storing wine. The other examples may veer from the norm, but here we return to the foundations that concrete walls are used for, albeit in a more dramatic fashion.
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Browse more photos of concrete in home design
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Browse more photos of concrete in home design