The cold-rolled steel roof has oxidized nicely over the fall and winter. It looks pretty good. Most of the steel siding is starting to turn as well, but it is pretty well protected from water, and with temperatures mostly below 50F, the oxidation rate is slow. Still, I’m pretty sure that by the end of the summer, most of the steel siding will have a decent patina on it.
However, the steel panels on the front of the house are very well protected. They basically never get wet. By mid-Spring they were looking pristine. So, I decided I would accelerate the process. Here is the siding in that area before I did anything…
I mixed 1/4 muriatic acid (standard stuff at Home Depot) with 3/4 tap water in a spray bottle. (Be very careful. Muriatic acid is, well, acid. It really does burn your skin and can destroy your eyes, too. Gloves and safety glasses/goggles are essential.) I simply misted the entire wall surface with the spray bottle. In 24 hours, as long as the temperature is above about 50F, the entire surface will be very rusted. You can see where you have missed spots and just hit those again. I’ll be curious to see how the accelerated oxidation compares in color to that of the naturally oxidized surface. You can already see that where water has bounced onto the wall, the surface is more orange. Anyway, I’m pretty happy with the results. I would be curious to know if an even milder acid would work (e.g., white vinegar). I bet it would, especially if the temperatures were a bit higher.
The roofers have nearly completed the steel siding on the house. I’m very happy with the results. We are using 2′ x 3′ 20 gauge cold-rolled steel flat panels. It is very inexpensive (~$2/sq-ft materials and labor), and I think it looks fantastic. It will rust to a reddish brown when exposed the weather for a few months.
On the main cabin we have had woodpecker problems over the years. Apparently the woodpeckers like to nest up high with a vantage point of the meadow. The gable end of the main cabin was perfect and they had made a mess of the tongue-and-groove cedar siding. We had patched with metal, but finally had to take drastic measures. My father-in-law had a guy apply galvanized steel sheet to the walls and then apply cedar shakes over that. This has mostly worked. Occasionally a wood pecker will attack, but after 1/2 inch of progress will give up. So on the pavilion, we’re taking the galvanized-plus-shakes approach from the get go.
Jose and gang started installing barnboard siding this week. It looks excellent. The barnwood comes from Trestlewood. They provided edged wood in random lengths and in widths of 4″, 6″, 8″, and 10″. By taking shorter lengths and a fair bit of narrow material, the material ended up costing just a bit more than virgin cedar siding. (A consistent irony of building green, is that reclaimed materials usually cost more than those cut fresh from the forest.) My cost for the barnwood ended up being about $3/sq-ft delivered, while #3 cedar siding currently costs about $2/SF, but usually requires staining, which would probably be another $1/SF. (You could leave the cedar to weather naturally, though, in which case it would be cheaper.) Incidentally, bids for the installation labor for this kind of board-to-board barnwood in Park City came in pretty consistently around $2.75-$3.00/SF including the labor to apply the Tyvek. This is probably on the low side because I have no window trim to install, although there are some fussy blocking details between the rafter tails.