Posted By: Drwood
Riding out an EF1-2 tornado in a timberframe - 03/12/14 05:07 PM
Riding out an EF1-2 in a Timber Frame
I recently joined the timberframe guild, and am also member in a few other guilds… I have dug through these posts extensively though not exhaustively and did not find anyone else having experienced a direct hit by a tornado, so I thought I would share my experiences as I am sure that those builders in the tornado alleys are questioned how this building style actually does in a storm of that violence.
This will be my first post:
A little background:
My education is in science and medicine, but during my undergrad I sat in on as many engineering courses as I could till I got kicked out for not being registered.
In 2007 my wife and I designed and subcontracted out a 4500 sq ft timber frame addition to an 1500 sq foot 1853 timberframe farmhouse. (the first project on the farm was jacking the structure and replacing the termite eaten sill beams and summer beams so this structure was solid after that.) The only reason we did not cut the frame ourselves was because of time constraints. In the end it was a 10x10 red oak timber frame cut on a CNC setup (beautiful frame) and put up by a group of very unprofessional laborers. [A WHOLE other discussion.] After the frame was erected, the 2 contractors involved quit (admitting they were in over their heads) and took over the project ourselves and proceeded to do 95% of the work ourselves with excellent results. The frame was wrapped in SIPs 4” walls and 6” ceilings.
Frame nearly finished pic incuded
The house is passive solar (and works stunningly well with a usual 1-2 cords of wood burned per year and no central heat, all electric setup with ave electric bills year round less than $100/month and often less than $70). We put in one heatkit.com masonary oven and 2 soapstone stoves and a ductless mini split by Mitsubishi (love that too but only used for AC).
House and homestead in winter before the tornado pic included
The house has 68 windows, something I would do a little differently if I had to again. It has james hardy concrete siding. We were originally going to do a (55 square) standing seam steel roof but after the lowest quote was as much as the foundation, excavation, frame and sips, I considered alternatives and eventually put on a slate roof , at a cost of $25k total instead of the quoted 110k for a steel roof. A good deal and possible with some strategies I am willing to share to anyone who asks.
The other structures on the farmstead (because they are/were historic and all took a direct hit in the tornado and had differing builds to be directly compared in the same storm of same intensity at the same time.) all buildings referred to on a north-south east west orientation as the faces of the buildings all orient like that and it makes it easier to visualize.
1. 25x30 pole barn approx 20 years old. Steel siding and roof. Enclosed on all sides with walls or overbuilt (by me) sliding doors. Survived but had dents and penetrations from large debris hitting the building. (pieces of fence and trees, a school bus stop hut, palates etc.
2. 10x20 tractor shed circa 1900 timberframe of American chestnut, wood siding, steel roof not tied down to sandstone foundation open without a door on south aspect. This building was wiped completely off the foundation, blown apart with the 6x6 beams snapping like twigs. Debris field was approx a mile radius. Timberframe replacement planned.
3. 23x40 one story historic school house circa 1900 built on a sandstone foundation (not tied down) slate roof, wood siding with vinyl on top. Antique windows of that wavy glass. Structure sortof survived. 5% slate loss, garage doors pressed in, windows sucked out, and the whole structure was picked up and turned with the walls bulging out and off the foundation. It almost exploded completely. (so stick built did poorly in comparison) Foundation pieces were moved and with all of that the insurance “totaled” the building. Due for removal and rebuilding this summer ( a timberframe in the planning stages of course!!)
4. 1850’s heavily modified 12x24 cairrage house timberframe now garage. Steel roofing and vinyl over wood siding. Damage minimal to roof and siding but there are some signs of movement in the frame and this structure is slated for a takedown, frame repair and resetup.
5. 40x60 bank barn 1911 build of American chestnut (remember the blight in that species was full tilt and the cheapest lumber was from the massive standing dead trees) 10x10 timber construction first floor with a unique scissor truss structure freespan upper level. Total ht from ground to peak 57’ It had been my hobby to jack and repair all the deferred maintainence on the ground floor and in 2012 I had steel siding installed. Steel roof on old lath originally for cedar shakes. This structure was nearly destroyed as the southwest corner roof, siding and wood ripped off, and subsequently according to the forensic engineer’s report, the pressure inside the building increased and pushed the north face (60’ wall) out 2-3 inches, and in fact through a ½” crack enough wind was pushing through to bend the steel siding piece out at a 90deg angle! On the west wall a (true) 2x8 chestnut wall support vertical member was snapped neatly in half as the wall flexed in. it snapped along the long axis (imagine breaking a 2x8 over your knee with the 2 side against your leg) This structure will need to be jacked up and have things realaigned. Good thing I have been practicing and have gotten good at doing very large scale jacking and repair on this structure…
So then the tornado:
We live in hilly southeast Ohio, and tornados are a rarity here. November 17 about 9:20pm we were watching a movie in the home theatre when the neighbor’s field of unharvested corn shot blasted the house. That’s when we heard the “roar.” The tornado approached from the west and moved almost exactly west to east hitting #5 and #1 above first and then driving the debris onward to the rest of the structures structures 3,4 were hit next, and last the house itself. By this point there was plenty of debris. I went running upstairs for my son and witnessed the windows getting sucked out along with whatever was sitting next to them, the “roar” was more of an intense vibration where heavy furniture was actually being moved and then large items impacting the house and roof and the sound of hundreds of slates being rattled around and ripped off was another layer. So literally I was carrying my son as the tornado passed directly over the house. I mean really, these storm chasers have lost their darn minds…
The aftermath was about 20 or more trees smashed, the buildings as above, a water tank with 1000 gallons (8000 pounds) got pick up and flung, and a horrendous mess. The tractor shed contained a bunch of sheet metal spares, old windows, which subsequently got painted all over the neighborhood. Now, in the 2012 june deracho, we clocked winds 60-80mph and didn’t loose a single slate on our house. This one ripped the annometer off at final reading of 122mph.
On the house we lost 3 windows 2 on the west wall and one on the east, the slates got lifted and lost many of those. Even the ridge cap was ripped off where the tornado’s path went across. The siding on the west wall was penetrated with wood debris from the barn!
On the inside of the house the frame did not budge even a millimeter on the foundation (and you can be sure we checked) the plumb and square was as good as it was after the terrible frame erection process had left behind. On the west wall of the house the incoming pressure wall of wind flexed in the sips so much that the trim around windows got pressed off by about 1.5 inches (the panel span is a 9x10’ with a centered 3x5’ Anderson 200 series double hung window). The SIP panels on the roof were attached by standard sip screws and held on perfectly.
While I do have good insurance, id rather not have this claim ongoing… instead of pursuing creative things I am instead dealing with this… So I am taking the opportunity to do the smaller timberframe structures myself and with some help. I will likely be posting more about that as spring turns to summer.
I am happy to expound on any technical details for those of you out there that are interested in the sip performance or frame performance. Please ask.
Overall it was over in a flash (a minute or maybe 90 seconds total?) and the overall feel inside the house was very secure, even on the second floor with less than 12” of material separating my head from the 120mph winds filled with debris.
I recently joined the timberframe guild, and am also member in a few other guilds… I have dug through these posts extensively though not exhaustively and did not find anyone else having experienced a direct hit by a tornado, so I thought I would share my experiences as I am sure that those builders in the tornado alleys are questioned how this building style actually does in a storm of that violence.
This will be my first post:
A little background:
My education is in science and medicine, but during my undergrad I sat in on as many engineering courses as I could till I got kicked out for not being registered.
In 2007 my wife and I designed and subcontracted out a 4500 sq ft timber frame addition to an 1500 sq foot 1853 timberframe farmhouse. (the first project on the farm was jacking the structure and replacing the termite eaten sill beams and summer beams so this structure was solid after that.) The only reason we did not cut the frame ourselves was because of time constraints. In the end it was a 10x10 red oak timber frame cut on a CNC setup (beautiful frame) and put up by a group of very unprofessional laborers. [A WHOLE other discussion.] After the frame was erected, the 2 contractors involved quit (admitting they were in over their heads) and took over the project ourselves and proceeded to do 95% of the work ourselves with excellent results. The frame was wrapped in SIPs 4” walls and 6” ceilings.
Frame nearly finished pic incuded
The house is passive solar (and works stunningly well with a usual 1-2 cords of wood burned per year and no central heat, all electric setup with ave electric bills year round less than $100/month and often less than $70). We put in one heatkit.com masonary oven and 2 soapstone stoves and a ductless mini split by Mitsubishi (love that too but only used for AC).
House and homestead in winter before the tornado pic included
The house has 68 windows, something I would do a little differently if I had to again. It has james hardy concrete siding. We were originally going to do a (55 square) standing seam steel roof but after the lowest quote was as much as the foundation, excavation, frame and sips, I considered alternatives and eventually put on a slate roof , at a cost of $25k total instead of the quoted 110k for a steel roof. A good deal and possible with some strategies I am willing to share to anyone who asks.
The other structures on the farmstead (because they are/were historic and all took a direct hit in the tornado and had differing builds to be directly compared in the same storm of same intensity at the same time.) all buildings referred to on a north-south east west orientation as the faces of the buildings all orient like that and it makes it easier to visualize.
1. 25x30 pole barn approx 20 years old. Steel siding and roof. Enclosed on all sides with walls or overbuilt (by me) sliding doors. Survived but had dents and penetrations from large debris hitting the building. (pieces of fence and trees, a school bus stop hut, palates etc.
2. 10x20 tractor shed circa 1900 timberframe of American chestnut, wood siding, steel roof not tied down to sandstone foundation open without a door on south aspect. This building was wiped completely off the foundation, blown apart with the 6x6 beams snapping like twigs. Debris field was approx a mile radius. Timberframe replacement planned.
3. 23x40 one story historic school house circa 1900 built on a sandstone foundation (not tied down) slate roof, wood siding with vinyl on top. Antique windows of that wavy glass. Structure sortof survived. 5% slate loss, garage doors pressed in, windows sucked out, and the whole structure was picked up and turned with the walls bulging out and off the foundation. It almost exploded completely. (so stick built did poorly in comparison) Foundation pieces were moved and with all of that the insurance “totaled” the building. Due for removal and rebuilding this summer ( a timberframe in the planning stages of course!!)
4. 1850’s heavily modified 12x24 cairrage house timberframe now garage. Steel roofing and vinyl over wood siding. Damage minimal to roof and siding but there are some signs of movement in the frame and this structure is slated for a takedown, frame repair and resetup.
5. 40x60 bank barn 1911 build of American chestnut (remember the blight in that species was full tilt and the cheapest lumber was from the massive standing dead trees) 10x10 timber construction first floor with a unique scissor truss structure freespan upper level. Total ht from ground to peak 57’ It had been my hobby to jack and repair all the deferred maintainence on the ground floor and in 2012 I had steel siding installed. Steel roof on old lath originally for cedar shakes. This structure was nearly destroyed as the southwest corner roof, siding and wood ripped off, and subsequently according to the forensic engineer’s report, the pressure inside the building increased and pushed the north face (60’ wall) out 2-3 inches, and in fact through a ½” crack enough wind was pushing through to bend the steel siding piece out at a 90deg angle! On the west wall a (true) 2x8 chestnut wall support vertical member was snapped neatly in half as the wall flexed in. it snapped along the long axis (imagine breaking a 2x8 over your knee with the 2 side against your leg) This structure will need to be jacked up and have things realaigned. Good thing I have been practicing and have gotten good at doing very large scale jacking and repair on this structure…
So then the tornado:
We live in hilly southeast Ohio, and tornados are a rarity here. November 17 about 9:20pm we were watching a movie in the home theatre when the neighbor’s field of unharvested corn shot blasted the house. That’s when we heard the “roar.” The tornado approached from the west and moved almost exactly west to east hitting #5 and #1 above first and then driving the debris onward to the rest of the structures structures 3,4 were hit next, and last the house itself. By this point there was plenty of debris. I went running upstairs for my son and witnessed the windows getting sucked out along with whatever was sitting next to them, the “roar” was more of an intense vibration where heavy furniture was actually being moved and then large items impacting the house and roof and the sound of hundreds of slates being rattled around and ripped off was another layer. So literally I was carrying my son as the tornado passed directly over the house. I mean really, these storm chasers have lost their darn minds…
The aftermath was about 20 or more trees smashed, the buildings as above, a water tank with 1000 gallons (8000 pounds) got pick up and flung, and a horrendous mess. The tractor shed contained a bunch of sheet metal spares, old windows, which subsequently got painted all over the neighborhood. Now, in the 2012 june deracho, we clocked winds 60-80mph and didn’t loose a single slate on our house. This one ripped the annometer off at final reading of 122mph.
On the house we lost 3 windows 2 on the west wall and one on the east, the slates got lifted and lost many of those. Even the ridge cap was ripped off where the tornado’s path went across. The siding on the west wall was penetrated with wood debris from the barn!
On the inside of the house the frame did not budge even a millimeter on the foundation (and you can be sure we checked) the plumb and square was as good as it was after the terrible frame erection process had left behind. On the west wall of the house the incoming pressure wall of wind flexed in the sips so much that the trim around windows got pressed off by about 1.5 inches (the panel span is a 9x10’ with a centered 3x5’ Anderson 200 series double hung window). The SIP panels on the roof were attached by standard sip screws and held on perfectly.
While I do have good insurance, id rather not have this claim ongoing… instead of pursuing creative things I am instead dealing with this… So I am taking the opportunity to do the smaller timberframe structures myself and with some help. I will likely be posting more about that as spring turns to summer.
I am happy to expound on any technical details for those of you out there that are interested in the sip performance or frame performance. Please ask.
Overall it was over in a flash (a minute or maybe 90 seconds total?) and the overall feel inside the house was very secure, even on the second floor with less than 12” of material separating my head from the 120mph winds filled with debris.