Mid 20th-century modern is some of the coolest design out there. Transporting California’s easy, breezy design to wherever else the homes were built – glass walls that blend indoors and out, enclosed ranch-style courtyards, and sprawling floor plans.
And while the Cali style imported well to other places– connecting occupants to the outdoors – Mid-Mod from the 1950s is a train wreck in terms of energy efficiency. And given the knowledge we have now about energy and water savings, many of the historic building specifications are text-book examples for how NOT to build homes – the worst and least of everything.
In the 1950s, attics were grossly under-insulated and often inaccessible. Windows are single-pane and metal-framed, which puts heat loss on a fast train OUT of a home. (Anyone who’s ever stood in front of single-pane windows knows what I’m talkin’ about.) Heating systems of the day (boilers, furnaces) are massive because they basically heated the neighborhood. And ductwork – the pipes that carry hot and cold air – leak like straws full of holes.
The industry standard for measuring energy efficiency is called the “HERS rating”. (Click HERE for more info.) Briefly, one point equals one percent energy use, up or down. A home built in 2006 has a HERS rating of 100. As energy codes become more stringent, that number should drop. AND older homes like MCMs have HERS ratings of 200, 300 or greater – two to three times worse than new homes.
In the chart above, HERS ratings for MCM are literally off-the-charts. Mid-Mod is the coolest in design, but the worst and least of everything in energy and water use.
Anytime you remodel or add on to a mid-century modern (MCM) is the perfect time to bring the home forward in terms of efficiency. And for you hardcore design purists, there are ways to do that that won’t impact the architectural integrity of a home – ‘like restoring an antique car but upgrading what’s under the hood.
WALLS – The walls of mid-century homes are two-by-four-framed. Sometimes they’re insulated, and sometimes not. If you can’t tell for sure, drill into an exterior wall in, say, a closet and poke around with a wooden skewer (WOOD, not metal) to detect the presence of batt insulation. Many utility rebate programs offer hefty incentives to insulate empty wall cavities, and it’s not as major as it sounds.
HEATING & COOLING – One thing builders did well in the 1950s and ‘60s was put in big furnaces and boilers. And I mean BIG – two to three times the sizes we’d use now. If you’re upgrading your home, have a heating specialist right-size your system. Even though they should by law, it doesn’t often happen. And the cooling systems I see in MCMs are usually whole-house fans or evaporative coolers. I recommend the latter if someone’s dead-set against air-conditioning (Did I say “right-sized”?) Again, utility programs usually have sweet rebates for high-efficiency cooling systems.
DUCTS – The piping that carries hot and cool air. It’s never sealed the way contractors should seal today (with epoxy (“mastic”) as thick as a nickel.) And it’s often run through below-grade spaces (like crawls) that are open to the outside. Good “home-performance” contractors should enclose and warm those, and seal up those ducts.
WINDOWS – Even though window salespeople have knocked on lots of doors, I still see single-pane, metal windows in MCM homes. Replace them with good windows that protect against winter cold and summer heat gain.
ATTICS – If there’s one area that almost always needs attention, it’s attics. MCM attics are notoriously shallow with as little as 18 inches at the ridge, and often, there isn’t even access. I often see about 4 inches of insulation in MCMs. To keep my clients comfy, I usually recommend 20.
If there’s any good news here, it’s that anything you do to help an MCM for energy- and water-efficiency will have an impact. Always, work with good “home-performance” contractors. Your utility provider usually has lists of certified companies they approve. Start there.
If you’re budget-strapped, the two areas you should address for greatest impact are usually uninsulated walls and old heating and cooling systems – ‘hands down.
If you have questions, reach out anytime.
IMAGES: Mile High Cooperative, 1951, photo by Hal Priest. HERS chart, author. Palm Springs home, OnBlueUnderCanvas.com