Change Order: Part One
Decay and insect damage in the sills and lack of footings in the existing foundation lead to changes in the scope of work
Every remodeling project begins with an exploratory inspection of the existing structure with the goal of gathering as much information as possible that might affect the design and the cost. “It is something that multiple people look at, and there is a checklist,” says project manager, Mike Eckert.
The challenge is to inspect as much as you can while being as non-invasive as possible so as to avoid damage to finishes. “It’s a question of how much destructive exploration we do ahead of time,” says Boardwalk Builders estimator, Don Stewart. “In the case of the foundation, we tested in two spots where we drove rebar down into the soil a couple of inches away from the foundation. In both locations we got solid hits.” That seemed to indicate the presence of a footing. Only a single course of block was visible above grade, and it appeared to be in good condition, with tight mortar joints and no cracks.
It wasn’t practical to verify those findings from inside. “The foundation wasn’t easily accessible from inside,” Eckert says. “The only access we had to the crawlspace was through the cellar, and there was maybe 10 inches of clearance.” And you couldn’t see much, he says, because the view was blocked by dirt that workers during a previous renovation had piled up around “mole tunnels” they dug to create working room.
The only access to the crawlspace was from the basement, but it wasn’t easy to get to and there wasn’t much clearance.
Shining a light into the area didn’t help much because the view was blocked by dirt piled up around “mole tunnels” that had been dug by workers during previous renovations.
The foundation mystery was solved shortly after demolition began. Once the existing soil was scraped away from the block wall, it was much easier to distinguish the split-face cap blocks on the original piers from the CMU blocks infilled between them.
After more of the wall was exposed, it was easier to distinguish the split-faced block that capped the original piers from the standard CMUs used to fill in between them.
With the floor system removed, the two-stage structure of the foundation is clearly visible. The original house was supported on block piers at the corners and third points around the perimeter. During a 1960s-era renovation, the space between them was filled in with cinder blocks. None of the blocks were set on a footing.
The homeowners were aware that there was some insect and water damage at the sills, but the full extent of the damage was not revealed until the siding was removed. Exposing the framing also revealed a style of balloon framing that was common in the area at the time the cottage was built. Unlike a platform frame, in which joists are laid on the sills and subfloor installed before walls are raised, in this case the studs were fastened directly to the sills, with joists laid alongside them.
Insect and water damage at the sills became apparent after siding was removed. Also revealed was a balloon frame, with studs attached directly to sills, and joists laid alongside them. The damage didn’t affect the plan because the sills, and joists were going to be replaced anyway, which would also require trimming the bottoms of the studs.
The damage to the sills and wall framing were of little consequence, because the plan had always been to replace the sills and joists, and the trim the bottom of the studs. What did matter, however, was the lack of footings under the supporting piers and the CMU infill.
That discovery ultimately led to a change order that would affect the foundation and the treatment of the existing frame. We’ll look at details in our next post.