Last year’s straw bale construction workshop season started with a huge project: the Eco Learning Center at Ferncliff outside of Little Rock, Arkansas. I recently hear from the host of that workshop that the 5300 Sf structure is just about finished. I am amazed at how quickly the project has moved towards completion, especially having read the mind-numbing facts that the host shared with me. It’s a great example of some of the “behind the scenes” numbers that go into building a house. I hope you enjoy the numbers.
-The slab has 3,300 fee (.62 miles) of ½ inch PEX tubing that was tied with 5000 zip ties in a serpentine fashion for the 3,900 square feet of hydronic radiant floor heat. The 5300 sq ft building is heated with a wood furnace/boiler with pumps using less than 7% of the power the 12 solar panels can produce.
-The total weight of the steel framing is 28,000 pounds and it was all hand-carried from the staging area to the slab, then assembled.
-The Straw bale “toe up” consists of 89; 4×4’s each 10’ in length running twice end to end around the 445 foot perimeter. To fasten these timbers to the concrete, 380, half-inch holes were drilled in the concrete, 380 wedge anchors driven and 380 more holes drilled in the timbers. For “grabbers,” 2,136 large nails (20 penny) were partially driven every 5 inches into the 4×4 timbers.
-4.26 miles of baler twine was used for “sewing” the walls and re-tying custom-sized bales.
-556 ceiling panels 30”x30” were milled out of OSB and pre-painted, two coats on each side adding up to 13,900 square feet of surface area painted. This is for the ceilings over the bedrooms. 95% of this painting was done by volunteers. and 95% of that was done by two women (Carol and Jo).
-25 pallets of rice hulls at 800 pounds per pallet equal 20,000 lbs. or 10 tons of material. This material was toted, poured, slung, scattered for interior wall and attic insulation. Another perspective: A five gallon bucket of rice hulls weighs 7 pounds and carried two at a time would constitute 1,429 trips to its final destination.
-Approximately 43 tons of sand and 14.5 tons of hydraulic lime, plus water were handled into a mixer, wheel barrowed to work area, transferred to scaffold to hawk and trowel to wall. This was done to plaster an 8,888 feet of straw bale wall area three times (26,664 square feet). It took 120 for the plastering and walls were wetted down at least twice per day during this process.
-Each of the four large bedrooms employed a different locally available material. A rock floor was made with rock salvaged from the old camp pool. A cement stepping stone clock was put in the middle of the floor to make it a “Rock Around the Clock” room. Another floor was made by putting about 3000 beer bottles bottom up in sand and then mortaring them. The third floor was made to look like field stone but is actually made from paper mache. The fourth floor was made with used conveyor belt that was cut into tiles laid over compressed gravel.