Business Articles - On the Job
Articles & Tips
On a recent project, my crew and I incorporated a number of traditional Japanese
building features, including a series of turned, structural cedar posts bearing
on natural fieldstone footings. The posts support a wide roof overhang, which
sheds its runoff directly onto a "moat" of 3/4-inch crushed stone that wraps
the building's perimeter between the foundation and the drip line (see photo
below).
The footing stones appear to "float" in the gravel bed but are actually embedded
in concrete on top of conventional, 10-inch-diameter sonotube piers that terminated
just below finished grade. We stood the sonotubes on Bigfoot bases (F&S
Manufacturing, 800/934-0393, www.bigfootsystems.com)
to ensure good distribution of the admittedly minor point loads they'd be supporting.
But the $14 Bigfoot form makes it simple to excavate for, support, and center
each tube precisely on layout, an otherwise fussy, time-consuming task.
Irregular Logic
To secure the stones to the concrete piers, we drilled a 1/2-inch-diameter hole
in each stone, tapped in a steel pin, and inverted the stone, embedding the
pin in the wet concrete (see Figure 1).
Figure 1. The decorative
footing stone elevates the turned wooden post above grade. The author drilled
the stone for a steel pin to create a secure connection in the wet concrete.
The challenge we faced on this detail was how to accurately scribe the ends
of the 4- to 5-inch-diameter posts to fit the irregular stone footings. What
I needed was one of those banded, multifingered molding copiers, but one flexible
enough to wrap around a post. I've never seen one of those, but, working in
pseudo-Japanese mode as I was, I figured a handful of bamboo teriyaki skewers
might do the trick.
The diameter of each post varied, as did the shape of each stone. And, because
we had to fit the posts between two fixed and unmovable points (roof and rock),
I decided that the surest method would be to cut a short length from the post
at each location and make a custom pattern for each of the stones. I plumbed
the cutoff atop the stone, using a bit of modeling clay to steady the piece.
I located the line points for the scribe by sticking the skewers, one at a time,
onto parallel rows of double-stick tape wrapped around the post. To secure this
mini-palisade, I then wrapped packing tape around the outside and slit it vertically
to unpeel the skewer pattern from the post (Figure 2).
Figure 2. The tip of
each skewer, affixed on bands of double-stick tape, defines the contour line
of the stone at the perimeter of the post pattern. The author then used chalk
to transfer high points from the stone and hollowed the pattern's end accordingly.
After hollowing the end of the sample post with a wide spade drill bit, I used
a jigsaw to cut to the scribe line. Then I began fine-tuning, rubbing chalk
onto the stone to reveal and transfer the high points to the post end. I hogged
out some of the waste using a cutter on a 4-inch grinder and fine-tuned with
a rotary rasp in my drill. Once the pattern piece matched up nicely on the stone,
I tacked it to the end of the full-length post to transfer its scribe line,
using an ordinary pair of dividers. To fill and seal the crude recesses inside
the final scribe, I packed a glob of thickened epoxy onto the end grain and
planted the post on the stone.
The roof rafters rested on a dropped purlin, which allowed us to stand the post
on the stone, a couple of degrees out of plumb, and mark its top end for a fit.
After cutting the post to its final length, we used a bottle jack to lift the
purlin about 1/4 inch, just enough to let the post slip into place. Releasing
the jack allowed the weight of the roof to press the post firmly into its epoxy
bed on the stone.
By Malcolm Meldahl
Malcolm Meldahl is a
builder and designer in Truro, Mass.
This article has been provided by www.jlconline.com. JLC-Online is produced by the editors and publishers of The Journal of Light Construction, a monthly magazine serving residential and light-commercial builders, remodelers, designers, and other trade professionals.
Join our Network
Connect with customers looking to do your most profitable projects in the areas you like to work.