In the mid-20th century, there seemed to be little reason to insulate a new California home. Mild winters and summers, combined with seemingly plentiful, inexpensive energy meant homeowners could crank up the heat without breaking the bank or worrying about their carbon footprint.
In the 21st century, however, we know that the beauty of floor-to-ceiling windows and exposed rafters, beams, and posts comes at a price. Insulating your home is one of the best ways to keep heating and cooling costs down and make your home more comfortable year-round.
What Is Insulation?
Insulation is anything that creates a barrier between your home’s interior and the outside to reduce the transfer of heat into or out of your living space.
Where Should I Insulate?
Having a green audit of your home can help you identify the areas most in need of insulation, but these are problem areas in many mid-century modern homes:
Walls
Exterior walls can be a significant source of heat exchange, so adding a layer between your home’s interior and the outside elements can yield big improvements in comfort and cost.
There are several types of wall insulation to consider, including batt and blanket, loose-fill/blown-in, and foam board/rigid foam. The type you select will depend on your home’s structure, how much insulation you need, and your budget.
Because installing in-wall insulation requires, drilling holes for a blower to access (at minimum) or cutting an opening large enough for rolls or panels to be inserted, the best time to do it is when you’re doing another remodel that includes wall work.
Ceilings
Many mid-century modern homes have exposed rafter beams and minimal insulation between the roof and the ceiling – a recipe for serious heat loss. As with walls, adding an invisible layer of insulation above the ceiling can pay significant dividends in comfort and cost savings while preserving a mid-century home’s unique beauty.
Material choice for insulating a ceiling is similar to that for walls. Consider adding ceiling insulation when it’s time to re-roof or do significant work on your ceiling (re-wiring, for example).
Floors
While most mid-century moderns don’t have drafty basements or crawlspaces, your floor can still be a source of heat loss. But it can be tricky to insulate them, both because of the floor-on-slab construction and the extensive use of in-slab radiant heat.
If you don’t want to pour a new concrete slab – and who does? – you’ll want floor coverings that address the need for insulation without diminishing the efficiency of your radiant heat systems. Thick carpets with pads aren’t generally the best bet. Cork flooring is a popular, era-appropriate option that can add some heat-retaining insulation without significantly affecting radiant heating.
Windows
Those iconic floor-to-ceiling windows that help make indoor-outdoor living such an appealing part of owning a mid-century modern are one of the most significant factors in poor thermal performance.
The original windows in most mid-century modern homes are single-paned glass with metal framing, offering little protection from heat or cold.
The ideal solution is to replace them with double-paned, energy-efficient windows, but this can be expensive if your home has many large windows. Less expensive – though less effective – options include mounting acrylic inserts onto existing windows or coating them with special products that reduce heat transfer.
Ducts
If your mid-century modern has ducts for heating or air conditioning, make sure they are properly sealed along the seams and joints, preferably using duct mastic rather than tape.
When Should I Insulate?
Any home without insulation can benefit from adding it, but because it involves opening walls, ceilings, or floors, it’s most cost-effective to do it when you’re doing other remodeling or building projects.
Some types of insulation can be installed with minimal intrusion, while others require more extensive “surgery” to your home. The best time to talk to your architect or contractor about insulation options is during the planning stage of any remodel.
Consult a Mid-Century Modern Expert
Because of the unique architectural features of mid-century modern homes, I highly recommend consulting an architect or contractor who specializes in mid-century modern remodels who can help you develop the most efficient, architecturally appropriate, and cost-effective strategy for insulating your home.