Why your roof trusses matter (more than you think)

The Invisible Skeleton

Once the ceiling is installed, you forget about them. But the trusses are holding up thousands of kilos of steel, water, and wind pressure. In the Philippines, we usually weld them on site. And that’s where the problem starts.

The “Welder’s Instinct”

Most welders just “eyeball” it. “Boss, it’s strong!” They use 1.2mm angle bars for a 6 meter span. It looks fine when empty. Then you put the roof on. Then a typhoon hits. The truss buckles. The roof collapses.

How to check if your trusses are garbage

1. The “W” Shape Look at the web design. Is it a “W” (Fink Truss)? Or is it random vertical bits? Triangles are strong. Rectangles are weak. If you see rectangles, call a structural engineer.

2. The Thickness For main members, 1.2mm is scary thin. It should be 3mm or 4mm angle bar for main spans. Or C-Purlins back-to-back. Don’t let them use thin “tubular” pipe unless it’s properly engineered. Rust eats tube from the inside.

Wood vs Steel

Wood: Termites eat it. It warps. It rots. Steel: Rust eats it. Winner: Steel. You can paint steel with Epoxy Zinc Chromate. You can’t paint the inside of a wood fiber. Just make sure they weld it properly. A “spot weld” is not a weld. It’s a suggestion. Full welds only.