December 30, 2011
Roofing the Armoury.
Colonial Williamsburg’s carpenters have spent about a month-and-a-half installing the roof on the Armoury. Laying shingles around the various chimneys has been an interesting and challenging part of the project, and since some of you have asked, we thought we’d walk blog readers through the roofing process.
The first step is to make 16,000 shingles. We can produce, on average, about 500 shingles a week, so the shingle production began back in March of this year and continued right up until the time of the roof installation. The cypress logs from which shingles were cut came from Surry County, just across the James River from Jamestown. Cypress is a local wood, readily available in Tidewater Virginia. The 18th-century builders of the Armoury simply bought a load of shingles and had them delivered to the site. Shingle-making was a big business in colonial times and roof shingles were bought and sold as a commodity just like scantlings and planks and iron and bricks. We, on the other hand, made our shingles at Colonial Williamsburg as part of the interpretive program.
Shingled roofs are very effective at shedding water… until you cut a hole into them and run up a chimney. Then things become more complicated. We solve the water problem around a chimney by cutting a groove all the way around the brick chimney.
Then sheet lead is set around the chimney and hammered into the groove to seal the water out of the joint.
Finally we build a little roof just uphill of the chimney, called a cricket or a saddle, to divert the water around the funnel of the chimney instead of letting it run down the roof right into the stack. We covered the small crickets above the forge chimneys with more sheet lead.
And we continue to run the courses of shingles up to the roof peak. It requires about 250 shingles to run one course 68 feet long (the length of the Armoury building).
An enormous cricket was built between the Armourer’s Shop roof and the Armoury Kitchen chimney. We shingled the larger cricket roof, and wove the shingles into the valleys of the cricket. Finally, lead flashing was set into the brickwork of the kitchen chimney.
In weaving the valley, each shingle was custom fit, wider at the top, tapering down almost to a point. The edges of the shingles were then angled to fit. It took about ten days to shingle the cricket, but the results are spectacular.
We may be a little biased, but we think it is one of the prettiest roofs in the Historic Area!
Contributed by Garland Wood, Master Carpenter.