Raising a Timber Frame
(Photo from Arthur, Eric and Dudley Witney. The Barn. New York Graphic Society, 1972. 217.)
This is a photograph from the early 1900’s of a barn raising.
To raise a timber frame safely, one first choreographs the sequence of events. We do this by writing out each step and going over the raising process together. We build timber assemblies on the site, stacked in the order that they will be raised. We know where our anchor points will be to secure those assemblies once they are raised. And we know who will be performing what task as the raising proceeds. Connecting timbers such as joists and purlins are stacked in the order of assembly. And we make ready the tools we will need during the raising.
On Raising Day morning we begin our day with a short reading and a talk on safety. We will entrust our lives to each other this day and so do not take our tasks lightly. The crane arrives and sets up. We don our hard hats and go to work.
Timber frames are most often raised in sections called bents. Each bent is rigged with strapping and come-alongs to strengthen it as it is being lifted. The most hazardous time is when one is being born and a bent while being raised is asked to carry loads it will never be asked to carry again once it is raised.
Let’s look at a series of photographs of a barn raising this past summer in Byrdstown.
Once the timber frame is raised we send the crane home. Our next task is to plumb and square the frame, which we do with a series of come-alongs and straps. We work from one end of the frame to the other, pegging all pieces of the puzzle together, and removing our rigging and bracing as we go. With the timber frame pegged and standing on its own, it is time to make it weather tight.
Enclosing a Timber Frame
There are three basic ways to enclose a timber frame: use an infill wall system between the timbers, conventionally wrap the timber frame with dimensional lumber and sheathing, or use structural insulated panels. Structural insulated panels—SIP’s for short—now see broad use. An SIP is composed of a core of urethane or styrene foam sandwiched between layers of oriented strand board. These panels come in sheets up to 8 feet by 24 feet, and measure between 4 inches and 6 ½ inches thick. The panels come pre-cut with rough openings for windows and doors and some manufacturers even supply wiring chases and boxes. The panels are secured to one another and secured to the timber frame with long screws. The result is a home that is quiet, strong, and well insulated. We are all woodworkers here, so I will not dwell on SIP’s. If you would like more information on these panels please pull up the website for companies like Thermocore or Winter Panel.
(Photo from Arthur, Eric and Dudley Witney. The Barn. New York Graphic Society, 1972. 217.)
This is a photograph from the early 1900’s of a barn raising.
To raise a timber frame safely, one first choreographs the sequence of events. We do this by writing out each step and going over the raising process together. We build timber assemblies on the site, stacked in the order that they will be raised. We know where our anchor points will be to secure those assemblies once they are raised. And we know who will be performing what task as the raising proceeds. Connecting timbers such as joists and purlins are stacked in the order of assembly. And we make ready the tools we will need during the raising.
On Raising Day morning we begin our day with a short reading and a talk on safety. We will entrust our lives to each other this day and so do not take our tasks lightly. The crane arrives and sets up. We don our hard hats and go to work.
Timber frames are most often raised in sections called bents. Each bent is rigged with strapping and come-alongs to strengthen it as it is being lifted. The most hazardous time is when one is being born and a bent while being raised is asked to carry loads it will never be asked to carry again once it is raised.
Let’s look at a series of photographs of a barn raising this past summer in Byrdstown.
Once the timber frame is raised we send the crane home. Our next task is to plumb and square the frame, which we do with a series of come-alongs and straps. We work from one end of the frame to the other, pegging all pieces of the puzzle together, and removing our rigging and bracing as we go. With the timber frame pegged and standing on its own, it is time to make it weather tight.
Enclosing a Timber Frame
There are three basic ways to enclose a timber frame: use an infill wall system between the timbers, conventionally wrap the timber frame with dimensional lumber and sheathing, or use structural insulated panels. Structural insulated panels—SIP’s for short—now see broad use. An SIP is composed of a core of urethane or styrene foam sandwiched between layers of oriented strand board. These panels come in sheets up to 8 feet by 24 feet, and measure between 4 inches and 6 ½ inches thick. The panels come pre-cut with rough openings for windows and doors and some manufacturers even supply wiring chases and boxes. The panels are secured to one another and secured to the timber frame with long screws. The result is a home that is quiet, strong, and well insulated. We are all woodworkers here, so I will not dwell on SIP’s. If you would like more information on these panels please pull up the website for companies like Thermocore or Winter Panel.
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