Saturday, August 14, 2010
Ramming Kitchen Walls
Installing the rammed earth for the kitchen wing took longer than the bedroom, not because we were less efficient, but because there was simply a lot going on down in the forms: two niches for a water heater closet and the washer/dryer, each with water, power, and gas; four small square windows near the top of wall, extra electrical circuits across the counter tops, an angled top of wall at the long sides with a light shelf, an eight foot long block-out to receive a pre-cast rammed earth panel to be built later, and some other challenges.
One specific change from the bedroom to the kitchen is that we reduced our lift depth to five inches for the entire height of the wall. In the bedroom we started with five-inch lifts and went to seven and eight inches. We wanted to see how the different depths would look in the finished wall and most of us agreed we liked the denser look. Reducing the lift depth meant more total courses; in a nine-foot tall wall, that means roughly nine more courses, and with each course taking between thirty and forty minutes, that's about four hours of added placement time. Actually, you make up a little time in ramming, because five inches will pack down a little more quickly than seven, but the smaller lifts clearly added to the total man-hours for kitchen wall placement.
In total, we worked about nineteen hours: three hours on Wednesday with a crew of six, eight hours Thursday with eight men, and eight hours on Friday with nine. We still have to come back Monday to prep and pour the bond beam, but then we'll be ready to strip the forms and move them to the second story of the bedroom volume. I'll take some close-up photos of the walls once the forms come off so we can have a discussion of how lift depth changes wall aesthetics. The photos in this post illustrate the formwork and conveyor set up for the kitchen walls.