Interesting article about the History of insulation and cavity walls.
Might interest some.
Link for the full article.
http://www.maconline.org/tech/rvalues/historyofinsulation/historyofinsulation.html
There is a story of a young architect today analyzing a building constructed in the 1950s with solid masonry walls and single paned glass used on the exterior of the structure. That young architect referred to the building as an “old, masonry, energy inefficient building.” In the present context of the 21st century, it is not energy efficient using today’s standards. But, when it was built, as with most other buildings at that time, very little insulation was used because energy was a cheap commodity and architects and owners did not require use of insulation in their building envelopes.
Insulation and other techniques for energy conservation are coming to the fore today. Therefore, masonry buildings and other building types have been upgraded with different types of insulation strategies. The use (in the 1950s and 1960s) of zonolite, vermiculite and perlite was used initially in the cores of concrete masonry units and wall cavity’s to increase the masonry’s marginal thermal performance. This satisfied the increased energy demands. In the earlier part of the 20th century, some insulation materials utilized on the inside of ice houses built in Chicago were horse hair and cork.
**CAVITY WALL HISTORY: 200 YEARS **
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IN THE EARLIER PART OF THE 20TH CENTURY, SOME INSULATION MATERIALS UTILIZED ON THE INSIDE OF ICE HOUSES BUILT IN CHICAGO WERE HORSE HAIR AND CORK.
Cavity walls are not new, they have been observed in ancient Greek and Roman structures. At the Greco-Roman town of Pergamum, on the hills overlooking the Turkish town of Bergama, a stone wall of cavity type construction still exists.
Sometime in the early part of the 19th century, the cavity wall was rediscovered by the British. Plans dating as early as 1805 suggest a type of cavity wall construction. It featured two leaves (wythes) of brick , bonded by brick headers, spanning across a 6" cavity. An early British publication (dated 1821) suggests the use of cavity walls as a means of protection against moisture penetration. The use of metal ties was introduced in Southern England sometime after 1850. These original ties were made of wrought iron.
Cavity walls were first built in the United States late in the 19th century. Figure 1 illustrates an alternate type of cavity wall system originally featured in an 1899 text book assembled for people engaged in the engineering professions and construction trades. However, it was not until 1937 that this type of construction gained official acceptance by any building or construction agency in the United States. Since then, interest in and use of cavity walls in this country has rapidly increased. This has resulted in extensive testing to determine cavity wall properties and performance.
Marcel