Repairs to a 17th-Century House Uncover a Few Puzzles
When a structure makes it to 345 years, there’s reason to celebrate. But, no matter how well it was built, nature usually finds a way to leave its mark. In 2009, Ben Haavik, team leader of property care for Historic New England, discovered that the circa-1664 Jackson House in Portsmouth, New Hampshire, had severe drainage issues related to a rear lean-to. What began as a straightforward structural intervention became something larger that’s opened up new questions, discoveries, and histories.
“The lean-to doesn’t attach to the roof structure,” says Haavik. “In many places there was a [one-]foot or 18-inch gap. The roof was held together by sheathing, which supported the whole structure, and it appeared that the lean-to was pulling away from the building.”
The exact age of the two-story lean-to is unknown, but Haavik estimates it was added to the main block of the house in the early 18th century. The house is the oldest timber-framed structure in New Hampshire. In 1924 the house passed hands from a descendant of Richard Jackson, who first built it, to Historic New England’s founder, William Sumner Appleton. Though there were alterations and additions that weren’t part of the original construction, like the lean-to, Appleton recognized that these additions were still historic and important in their own right, so he mostly left them alone.
The Jackson House sits on an embankment against a road. “The roof ends about a foot above grade near the road and the foundation is underground, so basically the first floor in the back is within the bank, whereas the first floor is just on a hill on the other side, so that leads to all sorts of drainage issues,” Haavik explains.
With the help of a $90,000 grant from the Land and Community Heritage Investment Program (LCHIP) awarded in 2015, Historic New England developed a plan to correct the house’s structural and drainage issues.
Step one included an archaeological survey. “We always build in archaeology a year or two before work [begins], because we never know what we’re going to find—and we always tend to find things,” notes Haavik.
Because the property has been owned by Historic New England for so many years and had already gone through a few renovations, Haavik and Kathleen Wheeler of Independent Archaeological Consulting didn’t expect to find much. In the end, they were pleasantly surprised. Haavik calls the discovery of 12,363 artifacts a “treasure trove of objects." In addition to ceramics imported from England, Portugal, and Germany, the archaeology crews uncovered a plate that is similar to one found at Jamestown in Virginia, the first permanent English settlement in what would become the United States.
“It sort of aligned Portsmouth and Jamestown,” explains Haavik. “Perhaps they were in the same markets, or were trading together.” It’s an interesting theory that could provide helpful insight into 17th-century trade along the east coast, and one that understandably excited the team at Historic New England.
Moving several feet of soil along the house led to the discovery of foundations of earlier structures that the team hadn’t been aware of. The civil engineer hired for the project had to redesign parts of the project so that the foundations would be protected.
Finally, in 2016, the team commenced the structural work. Historic New England stresses the importance of retaining as much of their properties' historic fabric as possible, so they decided not to rebuild the framing. The historic timbers were in good condition, save for the fact that they weren’t connecting to the rest of the house. The team decided to create the connection between the lean-to and the house with steel.
“Steel is a good option because you don’t need as much material as you would with wood,” Haavik points out. Though steel wouldn’t have been originally used when the house was built, the choice works because more often than not, architectural historians and preservationists want newer alterations to be distinguishable in some way. Historic New England traditionally paints interventions of this type a specific green color, which allows visitors to the Jackson House to separate the house's historic framing with the new.
Using steel had an added financial benefit. The project ended up being under budget, so in 2017 the team reapplied the funds to a new shingle roof and cladding repairs to the house’s exterior.
Though the project turned out to be a little more complicated than expected, the discoveries of discarded ceramics, tobacco pipes, and more adds to the story of the people who lived in the Jackson House for more than 250 years.