Nyob hauv kev tsim vaj tsev, tsis hais hom vov tsev thiab lub ru tsev, qee hom kev ua haujlwm yog tus qauv. Qhov no yog qhov kev siv ntawm lub rafter system, lub installation ntawm lub crate, tso "pie", uas muaj xws li ob peb txheej, xws li rwb thaiv tsev, waterproofing thiab lwm yam. Nyob rau tib lub sijhawm, nws tuaj yeem raug sau tseg tias rau kev ua haujlwm zoo ntawm kev ua haujlwm, nws yog ib qho tsim nyog yuav tsum xaiv cov khoom tsim nyog. Yog li, ru tsev mastic feem ntau yog siv rau rwb thaiv tsev, uas yog muag nyob rau hauv ntau hom