Saturday, March 17, 2012

Wood Skin

The cypress siding is almost done, and I'm very happy with it. It looks better than I imagined.

But here's what the first phase of the work looked like:

Those vertical "stripes" are 1/4-inch thick wood spacers, or furring strips. This was not part of my original plan. What got me thinking about adding some kind of spacer between the wall and the siding was seeing all the "button caps" that are part of the nails used to attach the building felt (the black material in the photo above). These caps protrude a bit, and the siding I planned to use has to lay flat against the wall (it's not typical lap siding that has space behind it). So I was worried that the siding would bulge out wherever it ran across one of the caps.

After doing some research and talking it over with a builder and another architect, it was clear that adding these spacers would be a simple and inexpensive way to solve the problem. And, because of the air space created, the siding would be able to dry quicker after humid or rainy days, helping it to last longer. In fact this spacer system is most often used precisely to help wood siding stay dry. Done deal.

With that settled, we could move on to the fun part. The boards started at the bottom.

Of course I had to come up with all my own details, such as this staggered joint where the boards end. I even designed the board. I always planned to use "channel rustic" shiplap siding for this house, as opposed to the more popular wedge-shaped lap siding, because I wanted it to create a flat surface against the wall instead of a bunch of slopes. But the typical channel rustic cross-section looks like this:

I wanted much narrower lines. So I reduced the recessed groove, or reveal, to 1/4 inch, and also added a slope so water would drain off easier:

The mill didn't even charge extra for this custom cut. That felt like a birthday present.

Also not seen too often is how I did the corners. Corner trim, shmorner trim:

It's a typical miter joint - the boards are cut at 45 degrees at the corner so they come together at a point. This helps give the effect of "wrapping" that I wanted for this part of the house; the siding seems like a skin stretched tight around four sides of the building. This wrapping would be interrupted if I followed the usual practice of adding a couple of vertical boards at each corner.

The staggered joints between boards are especially visible because of the differing shades and textures of the wood itself. I didn't expect that, but I like it.

The usual way to deal with the ends of siding boards is to just place them randomly, and as far apart from each other as possible. This is done for wood flooring too. But I decided to use the little joints where boards end to create the appearance of vertical channels or steps, so that within the continuous field of horizontal lines there would be subtle hints of vertical movement.

This is the "domestic" part of the house (bedrooms, bathrooms, kitchen), which I connect symbolically with the physical or earthly aspects of life, so a dress of dominant horizontal expression is fitting. But God is in our mundane activities as well. The sacred is in the ordinary, but less obvious, just as the staggered joints are subtle verticals (suggesting the spiritual, heavenly) within the fabric of horizontal boards.

One of my neighbors actually called me to say the workers were installing my siding wrong. "They aren't spacing the board ends; they're grouping them all together." So I had to explain that, yes, I actually designed it that way.

The nails provide an even subtler vertical expression. I could have used nails with heads so small they would be nearly invisible, but I chose ones with larger heads, to create dotted lines running from bottom to top. And as gravity pulls rain across the nails year after year, I expect little comet trails of sediment to form below each one, eventually connecting the heads and resulting in continuous lines. Time will unveil the vertical, heavenly nature that was embedded in this part of the house from the beginning. Architecture is one of the few four-dimensional arts.

(Oh yeah, and every primary nail line goes directly into a stud, and centers on a brick in the edging below. But you knew that.)

I considered buying #1 grade siding, which has almost zero knots. But two things pushed me to #2 grade: the high price of #1; and my realization that I like knots. When all these random slices of trees are pieced together on the wall, knots form constellations that never existed before. The "random" sizes and spacings of knots punching out of the uniform wooden field makes them reminiscent of stars and galaxies. Which means also that they have a visual family resemblance to the nine openings in the stone wall. And since those openings mimic a group of trees, we are brought full circle to another work of God in wood.

The dance of shadows and sun on this uniform field is another welcome layer of visual complexity God's world adds to the work.

I wonder if I should never design a wild, free-form building. Just make it regular and uniform. God will paint it with jazz.

The last images below show the siding as it is currently, which includes wood supports for the two scuppers.


  1. The house now truly belongs to the woods! The spacers were a great idea, too. I think, in a way, the spacers helped prolong the life of the sidings. It’s because the air flowing through the space will prevent rotting. Given that you’re an architect and had adequate insight about the sidings, I trust that they were installed properly. The spacers would be problematic if there were gutter leaks because the water can reroute to those areas.

  2. Chris,
    I have enjoyed your Church House blogs. It has been almost five years since the Wood Skin blog of March 17, 2012. Can you tell me how the mitered corner joints are performing? I ask because I have a similar project here in Florida. The GC and his carpenter are mightily resisting my design utilizing mitered corners for the cypress 1 x 8 channel rustic siding. They say they can't stand behind such a design, and prefer to use corner boards. Your comments are requested, wherever they may lead us.

    Bob Harris

  3. Hi Bob, sorry for the delay. Glad to have you reading the blog. The mitered joints here are performing great. They look about the same as they did 5 years ago. Not sure what your builder's concern is, besides just an avoidance of anything they're not used to. You could do what I did at just about every point in my project: tell the builder you know this is odd, but do it anyway; you're the one who will live with it, not him (for good or ill)!