Huge and Hollow

Northwood BeforeDeep into the winter of 2014, a banner stretched like caution tape across the front of Northwood Congregational Church. It implored commuters from Portsmouth and Concord, “Don’t Judge a Church By It’s Outside. Look for Restoration Coming Soon!” The red text on white vinyl was the freshest trim on the front facade. The porch sagged, the paint was peeling, and the carved finials once crowning the belfry were many years gone. Still, any driver might have noticed the huge fluted columns more than 30″ in diameter. An unhurried driver might have recognized the church as one of the best examples of Greek Revival architecture in the state, even in its dilapidated state. The slight skew to the banner underscored the meaning in its message. No passerby could have guessed the depth of commitment within the building committee and dynamism of the congregation behind it. The PTF crew restored their church from 2015-2016.

Early Photograph Northwood Congregational ChurchThe work was far-ranging, from repairing lightning damage in a king post to reproducing those finials from photographs. But the most impressive repairs were in the columns. The open portico is an important structural element, bringing half of the belfry weight to ground. But they are also an important decorative element, each stave carved with a tapered flute. When we first assessed the site, in winter of 2014, the deck supporting the columns sloped dramatically away from the building. The bottoms of the columns themselves were rotting, showing signs of decay, and the belfry leaned precipitously toward the road. Beneath the deck, we found a rubble stone foundation build on grade. There was no footer, no stone below grade, much less frost line. We supported the belfry on timber deadmen, staging, and steel I-beams while we removed the columns, replaced the foundation, rebuilt the deck, and repaired the columns. Arron documented the process in a series of photos, below.

He described the tilt of the porch as “not quite 45 degrees.”

Northwood porch foundation

The crew transferred the belfry weight to structural staging, timber “deadmen”, and a steel I-Beams that picked up the corners diagonally. The rigging was accessed and adjusted by the crew using ringlock staging. Once confident that the belfry was adequately supported, the crew began to cut away the old, decaying deck, to prepare the columns for removal.

Northwood porch, dismantling

Using a chain fall, Tom lowered the columns safely to the ground. A custom carriage was used to transport the columns to our shop. At nearly 20′ long, one column claimed the entire trailer.

Tom lowers the column safely to ground

After the columns had been removed, we focused on foundation repair. The parish hall foundation had a granite cap stone foundation that was built at grade; there was no frost wall or footers beneath it. The parish hall was supported on cribbing and jacks, and the granite capstones were carefully removed. Using extreme care, Bob Cantwell excavated the soils below the parish hall. Chris McKinnon poured substantial footers. Then he used a one sided form to pour a frost wall up to and underneath the parish hall slab. The granite capstones were replaced, and new sills installed.

The front wall of the church, under the columns, was similarly unsupported. The sagging deck was removed, and new footers, frost piers and frost wall were formed and poured. This foundation accepts the all of the weight from the front pediment, the portico, and half the tower loads.
Front portico footerThe crew replaced the deck framing with white oak. The dimensions and layout of the timbers were identical to the original. They were tenoned into mortises on the front sill, and pitched slightly away from the building.

Deck framing in white oak

The new deck will support the portico and tower above. The structural columns were hollow. They were constructed out of individual staves toe-nailed to a series of round wooden forms.
Hollow columnsWe assessed each individual stave for damage, trying to retain as much original material as possible. Where replacement was necessary, we cut tapered Eastern White Pine dutchmen and spliced them to the original flutes.
Individual stave repairEach column capital was inspected, repaired and painted. They were constructed from rings of boards stacked, rotated, and laminated together. Each top was modified slightly to accept a structural post.
Column capitalStructural timber posts were hidden inside the fluted columns. The posts were a necessary upgrade that will better transfer tower loads to the ground. The structural post was installed directly beneath the front exterior tie beam. The columns were not originally centered under the beam, and are not centered around the structural post.
Structural post inside hollow columnOnce the front half of the columns is installed, the structural post is completely hidden. The front portico looks as it did originally, but is much more structurally sound.
3 of 4 columns replacedOnce the columns were replaced, the crew could focus on structural repairs inside the belfry. The lower tower girts were replaced in-kind, along with the belfry bed timbers. All framing repairs were completed without dismantling the tower or removing the belfry. Once the structural repairs were completed, the exterior trim was restored. Balustrade elements were carved by hand, matching the few remnants of the original details, and early photographs. New louvers replaced poor reproductions. Bump outs were flashed with copper and new copper step flashing was installed at the base of the tower. The copper belfry roof was in good condition, and was modified slightly to accept the balustrade. George McKie, of Service Painting out of Lynn, MA, did a beautiful job of scraping, priming and finish painting. We are very proud of the result, but more than that, we are grateful to have been invited into this community. This project was so successful because the building committee recognized the importance of their landmark and committed themselves to appropriate preservation. They were one of the most responsive and knowledgeable groups with which we’ve ever had the pleasure to work.
Northwood Belfry

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