Prefab houses are generally made of steel structure, and the properties of general buildings depend on whether the structure changes the properties of the land. If it is fixed on the land, it turns the land into a construction property. The national standard "Unified Standard for Reliability Design of Building Structures" GB50068 was determined.

(1) Temporary structure with a design service life of 5 years,
(2) Easily replaceable structural components with a design service life of 25 years,
(3) Ordinary houses and structures have a designed service life of 50 years.
(4) Memorial buildings and particularly important building structures have a design service life of 100 years.