My uncle swore by a 3-4-5 triangle for every layout, but it cost me a day on a big deck job.

He said, 'Kid, if you can't trust a 3-4-5, you can't trust anything.' So I used it to square a 24-foot deck frame last month. The long run was fine, but over that distance, the small error in the triangle stacked up. The far corner was off by over an inch. I had to pull all the rim joists and start again with a laser. When do you guys switch from the basic triangle to a different method for bigger projects?

3 comments

3 Comments

gray87514d ago

Feel your pain... that inch of error is a real gut punch on a big frame.

reesej2715d ago

My contractor buddy swears by the diagonal measure method past ten feet.

emeryj6615d ago

Wait, does your buddy actually think that's more accurate than a laser? @reesej27, I've seen guys mess up the diagonal math on site all the time. A cheap laser measure gives you a straight number instantly, no squinting at a tape or doing geometry in your head. For long runs, any little bend in the tape or a bad angle on the diagonal throws everything off. I trust a digital readout over someone's tired brain at the end of the day.