Engineered I-joists yog feem ntau siv rau cov plag tsev tab sis hauv qee kis, kuj tseem siv tau los tsim cov ru tsev tiaj tus thiab cov tsev lag luam.

Peb yog tus kws tshaj lij kev ua haujlwm hauv Suav teb, tshwj xeeb hauv kev muab cov khoom lag luam zoo nrog cov qauv hauv Suav teb ntawm no los ntawm peb cov qauv kom sov siab, tiv tauj peb tam sim no.

Hnab khw