Timber Framing

  • Thread starter Thread starter brendonv
  • Start date Start date
  • Replies Replies 1K
  • Views Views 117K
Butch,I meant on my parents WiFi, not the forum. Uploads are almost instantaneous on cell service.

Sills are black cherry.
 
Cherry is rot resistant. There shouldn't be much moisture inside this building. There is sill sealer underneath anyway, but I don't think the architect spec's it.
 
Dave, what would be your assessment of how timber frame construction would hold up during strong earthquakes. They do collapse, but usually older structures here compounded by the very heavy tile roofs. Basically, I think of that type of structure as having resiliency, but you could certainly better inform.
 
Designing for seismic loads is a big deal in some states, like California. The engineers in the US want everything to be too stiff. Instead of relying on the braces to do their job, they want the sheathing to act as a diaphragm so there is zero movement. It's bullshit. In Japan, the buildings are allowed to move a little, and that allows them to survive better in an earthquake.
 
Yes, the large buildings and skyscrapers are definitely built to sway with earth movement, but i think the powers that be have become carried away with their attempts to make timber frame houses more resistant to damage. Now they make carpenters install metal hardware across main joints to pass code. The effectiveness I would think is questionable, but one thing is for certain, the hardware is ugly and much detracts from the woodwork. Removing it afterward might negate insurance coverage, so I'd want to cover it up with more wood in as subtle a way as is possible. I haven't seen anyone do that though, they just leave it to remain ugly.
 
Part of the problem with Japanese framing is that, from what I understand, the common building material is either port orford or yellow cedar, and in very small dimensions, like 100x100 mm. It's hard to get the joint strength in such small and low strength woods. In my opinion, at least here in with our abundant choices of wood and size, if a designer specs any steel, they are either a bad designer, are being forced by a bullshit code, or are trying to do something in excess of the limits of wood. I often see people who want to build post and beam, which is all plates and no joinery, because they think it is cheaper, easier, and stronger than mortise and tenon. In reality, it is cheaper to cut joints, than to buy the hardware for post and beam. And I have never heard anyone say that plates look better than pegged joinery.
 
Dave, quite a diversity in the dimensions used for timber frame construction here. What you say about 100mm square might be a standard for certain parts of the more common houses, but i think that you also will find heavier elements commonly utilised as well. Budget is a real constricting factor, when the funds are there, the standards readily change. Slow growing Japanese cypress was a preferred material for a long time, beautiful stuff that really shines when planed, with Pine commonly used for larger members or sometimes hardwoods. Show off locations within, used the treasured Zelkova or something else special on occasion. The domestic high quality woods have become rather expensive, as you say, cheaper substitutes have become common. Temples and shrines, they still pull out the stops because of large budgets. The carpenters doing those aren't very common either, specialists and often two years or longer projects. One thing that is very noticeable compared to earlier, is that with the imported woods that are already dry, you don't see houses that only are framed and have the roof on, sitting to dry for a few months. Nobody around, you could check those places out. People nowadays actually think that's an advantage with the hurry up no desire to wait to move in any longer. When it comes to strength and resiliency, personally i'd much more prefer having air dried over kiln dried any day.

Your pegged joinery that you show is really very attractive and reflects high skill.
 
Jay, I got the 100mm thing from my architect who visited Japan some years ago. At 6'-5" and a bright red beard, he drew a lot of attention walking down the street.:lol: I'm sure there is a wide variety of timber sizes in use, he just said that was the average in new construction. He had slides of a new temple that had just been completed. It was huge, and the master carpenter who oversaw the project was very young, I don't think he was even 20 yet.
 
20 is indeed very very young for a head miyadaiku (temple carpenter). I can only imagine him being the son of another, grew up in the shavings.
 
Absolutely amazing to have that skill to begin with, but at such an early age is astounding. And to be allowed to do the job, he must have had everyone's respect for sure.
 
Hay man like your questions.As a general rule on a vertical post your mortise should be about 80% as long as your joints are tight meaning your tenon fits snug so if you have 6x6 post with 6x6 rafters your mortise and tenon would be 5x5. furs are great to start and pines they are very forgiving spruce would be a good choice. Hope that helps.
 
Back
Top