It’s also giving us yet another opportunity to appreciate how points of view around simple subjects can sometimes differ.
For example, let’s say — hypothetically — that a contract specifies : “Wood Framed Roof Assembly: 8” high-density closed-cell spray foam urethane insulation (R-49 minimum).”
One point of view might be 8″ equals 8″. 7″ + 1″. Carl Yastrzemski’s jersey. The number of maids-a-milking. Trying from another perspective, there are 12″ rafters in the roof. That’s an 11 1/2″ nominal width. After spray foaming, you might expect to see 3 1/2″ of rafter sticking out. And that conveniently equals the width of a 2×4.
The other point of view might be that 8″ is really equal to 6 3/4″. Apparently when done correctly, 6 3/4″ of spray foam is equal to R-49. Toss in that it seals the house much better and it’s far better than R-49 of fiberglass.
One definition. Two very different points of view.
Math is funny that way.