Straw Bales
The use of highly-compressed straw bales as insulation, though uncommon, is gaining popularity in experimental building projects for the high R-value and low cost of a thick wall made of straw. "Research by Joe McCabe at the Univ. of Arizona found R-value for both wheat and rice bales was about R-2.4 (RSI-0.42) per inch with the grain, and R-3 (RSI-0.53) per inch across the grain. A 23" wide 3 string bale laid flat = R-54.7 (RSI-9.64), laid on edge (16" wide) = R-42.8 (RSI-7.54). For 2 string bales laid flat (18" wide) = R-42.8 (RSI-7.54), and on edge (14" wide) = R-32.1 (RSI-5.66)" (Steen et al.: The Straw Bale House, 1994). Using a straw bale in-fill sandwich roof greatly increases the R value. This compares very favorably with the R-19 (RSI-3.35) of a conventional 2 x 6 insulated wall. When using straw bales for construction, the bales must be tightly-packed and allowed to dry out sufficiently. Any air gaps or moisture can drastically reduce the insulating effectiveness.
Read more about this topic: Building Insulation Materials
Famous quotes containing the words straw and/or bales:
“Farm boys wild to couple
With anything with soft-wooded trees
With mounds of earthmounds
Of pine straw will keep themselves off
Animals by legends of their own:”
—James Dickey (b. 1923)
“No matter what disaster occurred
She stood in desperate music wound
Wound, wound, and she made in her triumph
Where the bales and the baskets lay
No common intelligible sound
But sang, O sea-starved hungry sea.”
—William Butler Yeats (18651939)