In the 1870s, young Laura Ingalls and the rest of her family in The Little House in the Big Woods had minimal insulation. When winter drew near families would stuff the gaps between their cabin’s logs with moss, dead leaves, straw, and any other natural materials they could find. Today we use much more sophisticated materials and methods of application, but the basic idea is the same: energy usage .
Insulation History
In Ancient Egypt builders used mud as insulation to keep desert homes cool in the summer, and papyrus lined clothing to keep their bodies warm in the winter.2 Ancient Greeks mined the first asbestos, dubbing the most common form of asbestos, chrysotile, from the Greek words “chrysos” (gold) and “tilos” (fiber) or “gold fiber”. They used the flame resistant material as insulation, and even dressed slaves in the material until they realized it could cause “lung sickness.”3 In addition, Greeks utilized air cavities between inner and outer walls in their houses to keep out either cold or hot air.4 Romans, known for their masterful aqueducts, learned to insulate their water pipes with cork. From the fall of the Roman Empire until the Industrial Revolution there were not very many advances in insulation technology—Europeans in the Middle Ages used wall hangings and tapestries to absorb moisture and keep out drafts, Vikings used mud plaster.5
During the Industrial Revolution, manufacturers turned again to asbestos, having lost the ancient knowledge that the material causes certain forms of illness. With the rise in steam-powered technology, industrialists used pipe insulation to keep steam heat in but keep fires from springing up. Asbestos was the primary insulation material through the 19th and mid-20th centuries—it was used in buildings, various transportation modes, and industrial applications.6 However, once the harmful effects of asbestos were rediscovered in the mid-1970s, builders scrambled to find a replacement material. People had been making due by stuffing cracks with cloth strips and newspaper, but builders began relying on fiberglass, a material that came in a variety of shapes including loose fill, blanket, board and molded pipe. Fiberglass is exactly what it sounds like: glass shredded into tiny fibers. Fiberglass works by trapping dead air between fibers.7
Interestingly enough, the history of insulation continues to repeat itself. First it was mud, then asbestos, and now it’s back to natural materials. Although there are some pretty advanced insulation techniques out there such as insulated concrete and gas-filled panels,8 environmental concerns have led to the rise of more ecofriendly forms of insulation such as paper cellulose, recycled cotton denim, and sheep’s wool.9 In fact, to a certain extent fiberglass is falling out of favor because it is an inhalation hazard and some brands contain formaldehyde.10
Why We Need Insulation
Insulation is all around us, but is almost always out of sight. This means that many people may not even know whether or not their home has attic or wall insulation. Unfortunately, without proper insulation half or more of the energy we use to heat or cool or homes can escape.13 In recent decades, there has been a growing push to become more energy efficient and environmentally conscious, especially as energy costs rise.
You can evaluate the effectiveness of the insulation in your home by looking at the R-value. The higher the R-value, the better the building insulation.14 Current standards in most parts of the United States call for at least R-13 for exterior walls and R-38 for ceilings (ceiling R-values are higher because heat tends to rise).15 If you want to figure out which type of insulation is right for your climate zone, use the GreeniacsGuide to help you insulate your home . Consider factors such as the moisture in your climate, your attic layout, your environmental priorities, and the type of insulation you are installing. Some types, like batts made of old jeans, can be installed without help.17 Others, like blow-in fill, you can’t install yourself.
We’ve come a long way since the 1870s, but insulation is just as important for us as it was for Laura Ingalls.
