Anatomy of a Well-Constructed Pergola
My dad has quite a lot of handyman experience (he has built swimming pools, renovated houses, fixes cars) but with the recalcitrance and aversion of children to anything their parents do, I never really bothered paying much attention, and so my brother was the one who learned the ins ands outs of fixing a washing machine. Just as I was ruing my inability to solder stuff though, Ken announced that I’d be helping him build a pergola, a porch-like extension to the Vallibonci house without the floor. Brilliant, now we’re cooking with power tools!
Having never done any construction work before, it is quite fascinating to see the building process from the ground up. I am now quite proficient at sanding wood beams, and know the proper building specs for rafter dimensions for a 3 m span. Also, I have strong urges to go out and buy a DeWalt impact drill, laser level and a chalk line. We just finished putting up the frame of the pergola yesterday, and though it might not look like much, a tremendous amount of calculation was done for this to happen.
A crash course on the techniques of good construction:
- Rafter is drilled into a bracket with four bolts with the strength to support a floor. Beam extends from the wall at a perfect right angle (we invoked Pythagorean theorem to accomplish this, which is harder than it sounds because the wall is not totally straight).
- Rafter is flush against the top beam since a 15 cm wedge has been sliced out of the bottom.
- Front post is held perfectly perpendicular to the ground with a stay post, which will later be removed when the final bolts are put in place.
- Two top beams dovetail and overlap neatly over the center post for added strength (you never want to simply butt the ends together).
- Since the ground is not level, front posts are cut to different heights (ranging from 2.005 to 2.095 m) so that the top beams are completely level.
I am pretty sure that Ken is highly amused at watching me fumble with a level (“It’s upside down”), but I appreciate him letting this city slicker newb act as his gopher. When I asked him how he learned to weld, he simply replied, “I grew up on a farm, my dad started teaching me how to weld when I was 10!” Sweet Jesus, when I was that age, I am pretty sure I was building walls with Legos. Ken’s pipe dream is to return to Australia and build his own house from scratch, and he has enough mason/plumber/architect friends around to help him out. I asked if we could swap some of my computer programmer friends for his tradesman buddies.
This project, more than anything else, has fully impressed upon me the need for the United States to switch to the metric system.