Pali mitundu yambiri yapawiri zomaliza za ulusi.Malinga ndi malangizo a kuzungulira kwandodo ya ulusi wothera pawirinyumba yosungiramo nyumba.pali mitundu iwiri: mbali imodzi ndi yobwerera kumbuyo.1. Zotsatira za ndodo yolowera mbali ziwiri mbali imodzi: (1) Pamene thupi lalikulu lili ndi zida zazikulu, liyenera kukhazikitsa zowonjezera, monga galasi lowonera, mpando wosindikizira, chimango chochepetsera, ndi zina zotero.ma bawuti okhala ndi ulusi wapawiri omwe amagwiritsidwa ntchito, mbali imodzi imakulungidwa mu thupi lalikulu, ndipo mapeto ena amamangiriridwa pambuyo poika zowonjezera.Mtedza, chifukwa zidazo nthawi zambiri zimasokonekera, ulusiwo utha kuvala kapena kuwonongeka, ndipo ndizosavuta kugwiritsa ntchito ma studs m'malo mwake.(2) Pamene makulidwe a thupi logwirizanitsa ndi lalikulu kwambiri, ndipo kutalika kwa bolt ndi yaitali kwambiri, ma bolts amagwiritsidwa ntchito, omwe ndi osavuta kupanga.2. Awiriwonsonga ziwiri zomalizakukhala ndi mbali ina yozungulira, yomwe imagwiritsidwa ntchito makamaka kulumikiza zigawo ziwiri zokhazikika.Mtunda kapena kukangana pakati pa zigawo ziwirizi kungasinthidwe mosavuta komanso mosavuta.