I-PVC (Polyvinyl Chloride) Ulwelwesi lokungena amanzi selidume kakhulu embonini yokwakha ngenxa yokusebenza kwabo okuphezulu nokusebenza kwabo okuhlukahlukene. Lezi zilwelwesi ziyingxenye ebalulekile yezinhlelo zesimanje zokuvimbela amanzi, ukuhlinzeka ngezithiyo ezisebenzayo ngokumelene nomswakama nokungena kwamanzi ezinhlelweni ezahlukahlukene. Enye yezinzuzo eziphambili ze-PVC ulwelwesi olungenziwa amanzi yi-exway yazo