In Dallas, Texas, Marc Kleinmann is working on plans for a house which the owner wants to look like the the iconic designs by California developer Joseph Eichler: lots of glass, a low-sloped roof, and roof beams that penetrate the exterior walls to support a broad roof overhang.
That style was all well and good back in the 1950s and ‘60s, but with our keener interest in energy efficiency, Kleinmann wonders in this Q&A post at GreenBuildingAdvisor whether it really makes much sense.
“Don’t know yet if those are going to be structural or not,” he writes of the protruding beams, “but either way I have can see some issues with several large 16-in. beams continuing from interior to exterior.”
He adds that while the beam detail could be designed so they did not actually penetrate the wall, “I can see lots of headaches with that method, too.”
It’s an interesting problem, and it leads to the larger question of aesthetics over practicality in modern architecture: Is the California Modernist style merely a “relic” of the age of cheap oil? That’s the focus of this week’s Q&A Spotlight.
One problem is thermal bridging
As Armando Cobo points out, many architectural styles have included beams that extend out from the house this way. One problem is thermal bridging, which is a path for thermal loss due to the lower R-value of wood versus cavity insulation, such as cellulose or polyurethane foam.
Cobo has several suggestions: First, stop the beams or timber trusses at the outside edge of the wall, install rigid foam insulation over the sheathing and then install faux beams on the outside. “It’ll help you with the thermal…