Thursday, January 13, 2011

13. Top Floor

With the walls for the main floor in place, the framing crew started on the top level. The floor itself was simple - floor joists were laid across the top of the walls, and sheets of plywood nailed down on top. I don't like springy, squeeky floors, so I spent a little extra money and used 1-1/8-inch SturdyFloor plywood instead of the flimsy 3/4-inch sheets that are commonly used these days. Adhesive was also applied between the joists and plywood to further eliminate squeeking.

The upper set of pre-fab walls were craned in and stacked on the deck. Most of these were plain stud walls with no sheathing, so they were quite a bit lighter than their lower-floor counterparts. This meant that they could usually be tilted up into place by two or three men, so installation only took a few days. There were also several walls that had to be hand-built on the site. As the walls went up, the pre-fab roof trusses for each section were placed on top of them in groups. These would then be moved by hand to their proper spacing and nailed or bolted in place. Almost immediately, another part of the framing crew would start nailing the roof sheathing onto that section. This locked the trusses in place and stiffened up the whole structure.

My framing contractor had talked me into using TechShield 5/8-inch roof sheathing. Under most circumstances, TechShield is a wonderful product.  It has a layer of aluminum on the underside, which reflects radiant energy back into the house. This is ideal if you are going to have an attic with an insulated floor, but I plan to have all the insulation in the roof itself, with a room-temperature attic.  This is known as an unvented or "hot" roof, and is accomplished by spraying expanding foam insulation between the rafters, right up against the roof sheathing. I found out later that TechShield does not recommend their product for this application, because the foam has a hard time adhering to the shiny aluminum while it's hardening.I'm hopeful that I'll find a solution for this dilemma.

 By this time, the vaulted ceilings in the dining room, library and bedrooms were starting to look rather impressive. The framing crew was fearless, scampering across the great spans to nail on the roof sheathing.  Even with safety harnesses, it was scary to watch them. Once all the exterior sheathing was installed, the house looked great -  clean, fresh wood!