ConX: Modular steel construction

ConXTech is a Bay Area company that has finally brought the steel frame into the 21st century.

Now, that phrase trite, but what they have mass-customized the design of steel beams and then greatly simplify the assembly. It reduces design time, reduces the amount of labor needed, reduces energy expenditures, and provides a sturdier and more flexible alternative to wooden frame structures. Those stick-built structures are the most common design of 1-5 story residential construction, however, ConXTech is looking to make 5-12 story structures affordable as well. To do so, they have approached the whole building process in a slightly different way.

With ConX, the architect must involve the manufacturer in the design process, as the company custom builds the structure offsite in a factory. ConXTech needs to schedule the amount of work and materials necessary, while the architect needs access to their computer components at the schematic design phase. Still, it’s really not unlike the conventional process in which plans are sent to a structural engineer for engineering work, just that the engineer is the manufacturer too. Integrating the manufacturer reduces overhead, while entering the design development phase with a working model of the structure keeps the building lean and reduces the number of design changes that result from unexpected structural revisions.

So, once the project does reach construction, the CNC robots cut out pre-designed structure members to specification, as each piece is needed on the job site, delivering the product only as necessary. The system consists of vertical and horizontal beams, joining elements, wall panels, whole flights of stairs, and various other parts for specialized situations. Because the factory environment allows for meticulous control and use of accurate cutting, the frame and all other elements are extremely precise, resulting in better quality and speedy assembly. The frame itself is put together using snap-in-place fittings that a steelworker then bolts into place to meet code.

It’s a persistent myth, perpetuated by traditionalists, that steel is not a sustainable construction material, due to its embodied energy, which is around eight times that of wood. However, embodied energy, that is, the amount of energy required to make the materials and then assemble them on-site, rarely exceeds 20% of the total energy required for a building torn down after only 50 years. Steel frames overwhelmingly outlast that timeframe (steel-framed buildings from the 1880s are still around, and we have no idea how long they will ultimately last), so the percent of energy the frame requires diminishes in relation to heating, cooling, and interior renovation costs. They also use much less material, allow for greater density, and when they are torn down they can be wholly recycled, but I’m digressing here.

Forest Hills’ Brown House

Upper Northwest has a reputation for having bland architecture, with the exception of pre-Depression Chevy Chase. But that’s proving itself to be a not completely true perception.  Down at the eastern end of Audubon Terrace in Forest Hills there’s a real treasure of modern architecture, almost completely buried the trees of  Soapstone Valley.  Although it’s been a house I’ve admired since a stopping a run in the valley back in high school, Modern Capital clued me in to the house’s authorship by the definitive SoCal architect, Richard Neutra.

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The residence, known as the Brown House, was built in 1968, only two years before the architect’s death. It is the only example of that architect’s work in DC, and one of only a few on the East Coast. More photos under the fold.

Good Architects: McInturff Architects

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To make an unwarranted generalization, DC architects like their buildings heavy and somber. Even in the recent fad of light and clean glass facades, the buildings have been rather self-serious and blockish looking, a consequence of clients demanding efficient floorplans from architects who themselves were trying to be cool and modern without upsetting the polished and poised look DC has in the collective consciousness and legal structure. This fretful indecision can be a bit like the jeans and sportcoat look – crisp but comfortable, hip but conservative.

McInturff Architects offer a wholly different approach. They’re (post)modern(ist) but a little witty and also aiming for comfort. Their mostly residential oevure consists of excellently-composed buildings that respond coyly to the conditions of the site. In doing so, it avoids falling into limpid styles while also carefully respecting historic and distinctive architecture elsewhere. As for aesthetics, the practice cleverly contrasts gentle and warm elements with bold minimalism in beautiful light-filled spaces. As their projects are primarily private, it’s trickier to see their work than Esocoff & Associates‘. But down in Georgetown, anyone can at least see three buildings, and go into one of those.