Feem ntau, 3 ~ 6 tee roj tseem ceeb tuaj yeem npog thaj tsam ntawm 10-20 square metres, uas yog qhov loj ntawm chav tsev. Nyob rau hauv cov xwm txheej tshwj xeeb, kev siv cov roj tseem ceeb tuaj yeem nce ntxiv. Piv txwv li, thaum lub tsev kho kom zoo nkauj tshiab yuav tsum tshem tawm formaldehyde, 8 tee ntawm purified thiab tshiab tseem ceeb roj xyab tuaj yeem siv.
Txhua chav yuav tsum muaj cov cua sib txawv, piv txwv li, chav nyob yuav tsum tshiab thiab ci, thiab chav pw yuav tsum sov thiab ntsiag to. Yog li ntawd, nws raug nquahu kom muaj lub tshuab ua kom zoo nkauj hauv cov chav tseem ceeb, nrog rau hauv chav dej, vim tias chav dej yog qhov chaw ua kom muaj hmoo hauv feng shui, nrog paj, tshuaj tsw qab, thiab dej.