When he bid the job, the author knew that fulfilling the architect's vision for a sleek, modern interior in this 150-year-old timberframe house would be riddled with challenges. Nothing was plumb, level, or square; and there would be very little interior trim camouflage defects.
One of the first orders of business was to provide a center bearing wall in the basement. After cutting through the thin slab, the author's crew dug a trench the length of the basement for a new reinforced concrete footing.
To accommodate the bearing walls for a stairway, the 12-inch-deep by 24-inch-wide footing widens to 5 feet at one end of the basement.
The floor framing was removed in sections and interior bracing installed to stabilize the walls; tall posts supported the floor system above.
Instead of trying to fasten new floor joists to the rotten sills, the crew placed new 2x4 pressure-treated sills on the inner portion of the wide foundation, then set a double-LVL rim joist on top to catch the ends of the new I-joists.
Diagonal braces prevented the exterior walls from spreading as the floors were reframed, a section at a time.
Carpenters removed the bottom clapboard courses and removed the rotted sills from the exterior, replacing them with built-up pressure-treated 2x8s. Then they fastened the new LVL rimboards to the built-up sills from the interior using GRK screws. (See the drawing " Sill Retrofit " on page 4 of the PDF for more details.