... years since construction; ... years old (of a building)
Prefix used before a number of years to indicate the age of a building since its construction. Common in real-estate ads, e.g. 築10年 means '10 years old'.
It's a 5-year-old apartment building.
built in ...
Suffix used after a year or era name to indicate when a building was constructed. Often seen in property descriptions, e.g. 1980年築 means 'built in 1980'.
This house was built in 1990.
This condo is 10 years old.
This apartment was built in 1990.
new building; new construction
structural alteration; reconstruction; remodeling
building addition; extension; adding a room
castle construction; fortification
relocation and reconstruction of a building
construction; building
harbor construction; port building · man-made harbor; artificial port
repair; renovation; restoration
reconstruction; rebuilding
reducing floor space during renovation
rammed-earth construction
old building; old construction
embankment; bank; dike
age of a building; years since construction
landscape gardening; garden landscaping
after construction; since building
relatively new; recently built
From the kanji 築 (build, construct), used as a bound form in building-age expressions.