America’s First Super-Insulated Buildings
In the 1800′s and into the early 20th century we used to get our refrigeration done using ice–including during the summer. Ice was harvested and stored in specially designed buildings and then distributed/used as needed. I recently happened across a thorough article on the topic in the journal of Early American Industries: The Chronicle Vol 66 #4. There is much interesting history in the article, but the relevant part was about the specially designed buildings. They were often made with none other than double stud walls with 10-12″ off sawdust insulation. In other words: cellulose! For those that are just starting to read this blog, our super-insulated home is exactly that: double stud, 2×4 and 2×4 walls, with 12.5″ of dense packed cellulose. I thought we were on the forefront of super-insulation design by having such a wall system, but we are actually implementing designs that are over 100 years old!
The author of the article, Paul Wood, in addition to fielding questions, kindly sent me high resolution images of plan and layout designs for a typical farm (non-commercial) ice house. The images, shown below, are from The October 1914 Vermont Department of Agriculture Bulletin. Here are some of my observations of the assembly:
- The double stud wall has a 4″x10″ bottom plate, with 2 sets of offset 2×4′s connected and spaced with a single horizontal 2×4 roughly mid-way between the top and bottom of the balloon framed studs.
- The exterior sheathing consists of a single layer of 7/8″ tongue and groove boards faced with “waterproof insulating paper” and sided with novelty siding or similar. The interior is sheathed with 2 layers of 7/8″ tongue and groove boards sandwiching similar paper. Unfortunately, I am unable to provide any insight into what the composition of what this insulated paper might be. Perhaps it was simply tarred felt paper? The double layer of interior sheathing is interesting; perhaps this was just to protect the insulating paper?
- I was surprised and impressed to see that triple pane glazing was used!
- There is a sophisticated appreciation of air flow and drainage.
- “Tarred Felt” was extended vertically part way into the top of the stem-wall–a detail whose purpose I am not sure of.
- Although the diagrams below show more sawdust used for horizontal insulation above the ice, Paul Wood informs us that marsh grass, and occasionally straw, up to 24″ thick, was commonly used directly on top of the ice. Marsh grass was preferred for its rot resistance. I wonder if there is a lesson here that would be worth re-learning? Folks who are interested in natural building and straw-bale design need to be vigilant in protecting the bales from decay–perhaps marsh grass bales would be a useful alternative?
- Noted in Paul’s article and not on the diagrams, white-wash was sometimes used to keep the ice-house buildings cooler. Also, the sawdust would have to be replaced annually, since it would degrade.
Click on images for high-res versions