To Raze or Raise
by Thomas O. Green & T. Bradford Green
The early 19th century barn located on High St. in Abington, MA defiantly remained standing after two decades of weather related insult and damage.The shingles had been blown off the left side of the roof twenty years ago. The sheathing, if present, was rotted. The rafters in several sections of the roof were hanging precariously, threatening to impale anyone foolish enough to walk beneath them.Of course walking beneath the rafters had the added risk of collapsing through the substructure and ending up in the cellar below.Anyone eye-balling the structure briefly would logically conclude that demolition was the only reasonable option.But for the owner of the barn, it was never a question.The barn would be restored and raised back to its original condition.
In mid-March of 2005, the owner contacted Tom Green of Colonial Restorations.Colonial Restorations has specialized in the structural restoration of post and beam buildings since 1981.After many careful hours, partner Tom Green reached the conclusion that the project was doable, but most likely not realistic.Tom understood that the whole project, if it became a reality, was to be a challenge.The landscape around the barn made the use of a crane to reframe the roof impractical.Actually that was a plus for the small three man company, as they did not own one.Anyways, two estimates were prepared, one basically for a new roof structure and the second floor deck.The second estimate essentially covered the reconstruction of the substructure including sills, beams, joists, and the granite support columns.The estimates also included a warning that the project might also increase in scope and most likely was not economically realistic.Once mailed out, the estimates were soon forgotten about.Colonial Restorations made the assumption that the owner had finally succumbed to the reality that the barn was doomed to either collapse on its own or be razed, hopefully salvaging some of the beams.However, the barn restoration was never in question.
The following spring, Tom received a thank you card that said, “I would like to schedule the project. Thank you. Linda.”The note included a large deposit.It took Tom half a day to figure out who the nice lady that sent the check was.Once he started remembering the condition of the barn, Tom wasn’t 100% certain that they were happy to receive the check.However, the project was scheduled for the next year (May 2006).
As the reality of tackling the project sank in, it became obvious that a careful plan would have to be developed, redeveloped, then thought about some more.The design and erection of the framing was important.However, the specifics of stabilizing the good and bad sections of the roof, along with the exact method of rigging to join together the large timbers was more important.Doing it thirty to forty feet in the air added to the excitement.
Phase One – Emergency Shoring
In December 2005, on a site visit to plan and think through the different scenarios of rigging, staging, and structural layout, it became very obvious that the deterioration of the failing sections of the barn was progressing much faster than expected.It was decided that in order to prevent continuing failure and the possibility of the damage snowballing into a catastrophic event, some controlled demolition, supplemented by careful shoring of the more adequate beams was needed.In January 2006, Colonial Restorations spent a week shoring up the roof and substructure.
On many occasions during the initial phase, everyone was told to leave the barn so that the Tom Green could carefully remove some of the rotted, interwoven roof members.The art of removing the failed structural elements hanging precariously was like playing pick up sticks.By the end of the week, the roof was stable enough to resist the weight of the winter’s snow so Phase 2 could become a reality in the following summer
Phase 2
By June of 2006 the layout and materials lists had been prepared.The beams for the roof were on site and separated into designated stacks.When they started in July, once again the condition of the rotted structure had become much worse.Stairs that only six months ago were adequate to climb from the first to the second floor had collapsed.Some sections of the roof scheduled for replacement which only a year ago had a roof like shape now hung in place.Large holes existed in three places.It was clear that the barn would not have lasted another winter.
The roof consisted of six bays.Each bent had a principal rafter which was tenoned to its matching member at the ridge line.The lower end was tenoned into the overhanging tie beam at the top plate level.About one third of the way up the roof, a purlin ran between the principal rafters.Secondary rafters ran in between the primary rafters.They were angle cut and nailed at the ridge and onto the top plate.Colonial Restorations also added steel brackets and 2×8 nailers at the top plate level to ensure the roofs’ stability against the wind.
Because of the original construction lacked a ridge pole, many of the rafters on the good (right side) of the roof had sagged as their co-part had fallen away.The first task was to stabilize the right side of the roof.Some rafters were jacked, although the roof line never became straight.Come-a-longs were also set up to stabilize the top plate level of the building.Once it was felt that the building was in control, the fun began.The goal was to replace one bay at a time, thus reducing the risk of damage.A complete staging of 2x10s was laid on the tie beams thus allowing the company to work off a stable surface.Tom began the game of reverse pick up sticks and carefully cut sheathing and removed rafters.Of course in some cases, the rafters acted on their own and fell once the sheathing was cut.Partner Brad Green’s primary role in the project was to cut the joinery in all the beams, staying at least one week ahead.Of course he had to do this despite being asked continuously to help in the rigging process.
Each section of roof proceeded as follows.The top plate section with its self supporting, diagonally tenoned joints was raised into position and placed on the tenons of the corresponding posts.Most of the hoisting was done using chain falls which were purchased special for the project with desired chain lengths.This method was chosen over utilizing electric hoists which were far too heavy to move into place when working off of ladders.Come-a-longs were another option that was only used minimally due to their slowness and required much more energy to be exerted to use.
The tie beam running from the internal queen post to the top plate locked the top plate into position via a over under half lap.Each beam required a different set-up for rigging to hoist it into place.This constant on-the-feet thinking was ideal for the smaller company with a plethora of rigging experience.
The progression of each section proceeded roughly as anticipated.They made templates out of 2x8x28’ pine for the first couple of principal rafters.After that, it was determined that the joinery could be cut accurately without the templates.The principal rafters had to fit the ridge joinery, the top plate mortise and tenon, as well as the tenon from the queen post, which in this barn extended past the top plate level to the rafters.They installed the purlins in the same alternating pattern as the original layout.This helped ensure that the strength of the rafters would not be overly compromised by the joinery on each side being at the same elevation from the top plate.By the time they reached the fifth and sixth bays, Tom began planning for Phase 3 (the substructure) and Brad took over the rigging and hoisting responsibilities.Finally, in early September the pine bough was lifted to the peak and the roof structure was complete.
Phase 3 – The Substructure
The reconstruction of the substructure progressed one bay at a time.Each section was composed of 8×9 oak sills, 8×8 tie beams, and 4×8 joists.The beams were tenoned together, while the joists used a half lap – pocket system.One unique aspect of this project was half of the barn involved beam replacement from underneath.In the other half, the flooring was removed and the beams and joists replaced from above.This approach was taken because the flooring in the rear of the barn was still sound and aesthetically correct.The flooring in the front half was rotted except for a 14’x20’ section which the rotted substructure was covered with a 6” concrete slab overly reinforced with both re-rod and sheep wire.Removing the concrete with a jack hammer was time consuming.This task was made more difficult as the rotted timbers below collapsed as sections of concrete were removed.Once the subfloor was installed, twelve granite columns were reinstalled for vertical support under the new substructure, replacing the forest of thirty to forty supports that had patched things up in the past decades.
The final element of the structural restoration was the second floor decking on the left side of the barn.The 4×8 oak joists were installed with a little creativity as to create a more level floor above.
With the transformation of this historic barn almost complete, it is nice for Tom & Brad to sit back and reflect on the project.This undertaking exemplified what some people will do when they simply fall in love with an older building.The building hold a piece of history that has long succeeded the original builders and owners. It becomes a member of their family and they develop a long lasting respect and appreciation and they are willing to do whatever it takes to save it.
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