59: The Outside Corners

I have avidly watched houses being built my whole life. Even as a kid I remember going by construction sites and watching the carpenters turn a pile of lumber into something special. I still remember the day we went by a site and a carpenter asked us if we wanted some nails. He must’ve sensed that’s what we wanted but were too timid to ask. He allowed us to take one handful of nails each. When we walked away with that treasure, you would have thought we just found a way into an Egyptian pyramid. Now that we had some nails, we could build something ourselves.

So, in all this construction watching over the last 50 years I’ve seen enough to be able to ask, why did they do it this way or that way. More importantly, I’ve been able to ask why “didn’t” they do this, or do that. So many little things, that would take almost no time to do, and very little (if any) additional expense…but would yield so much more. So, in my house I vowed to DO those little extra things… the outside corners are a good example.

I said previously that my outside corners have 5/8” sheathing on both the inside and the outside; thus making them a form of a shear wall (also known as a diaphragm wall). They were installed to increase the house’s ability to withstand the racking forces of high winds. The inside sheathing was installed when the wall was framed, which left the outside sheathing to be installed after wiring and insulating the space.

I wired the space with two runs of 12-2 (2 conductor with ground) so I would have an extra wire if ever needed. Then I caulked all the seams of the inside of the wall with painters caulk. This is part of the “airtight drywall approach” which reduces the amount of air leaking into the wall assembly. Less air infiltration means the insulation works better. Kraft (paper) faced fiberglass insulation batts came next. Then, the outside sheathing went on and because it is part of a shear wall it was nailed with number 8 galvanized nails at roughly 3” spacing all the way around. In case you’re interested, that’s about 120 nails on each fullsize piece of sheathing. Thank goodness for nailing guns.

Number 8 nails at 3” spacing on 5/8” sheathing provides a LOT of shear resistance. Most contractors use number 6 nails at 6” spacing on one layer of ½” or even 7/16” OSB. That’s not good enough for me; and the cost increase of using more and better materials was insignificant; rough estimate, $25 for the whole house.

While the dollar cost of these modifications is small, there is an increase in the time it takes to build them, sometimes a significant increase in time. So, I can see why most contractors don’t routinely build this additional protection into their product unless required by building code or as a special request by the owner. Since I have the time, including these little improvements in my home is a no-brainer.