Choosing a year to build: avoiding Kim Lau and Tam Tai

Before building, Vietnamese check the owner's age. The two most agreed factors are Kim Lau and Tam Tai.

Lunar age

Lunar age = current year − birth year + 1 (e.g. 1990 → 37 in 2026).

Kim Lau

You "hit" Kim Lau when lunar age mod 9 is 1, 3, 6 or 8 (harming self, spouse, children, livestock respectively) — avoid building then.

Tam Tai

Three consecutive "hazard" years per trine group — also avoided for groundbreaking.

Workaround: borrow an age

If you must build, a compatible person can "borrow age" to perform the groundbreaking.

Check quickly

Use the build-year tool, plus Tam Tai and house direction.