Nice to see you today ,Mr.Thomas
The issue you described can have several causes; before proposing a definitive fix I need measured data: water pressures at inlet and at floors 1, 6, 14 and roof during peak, leak rate (L/hr), plumbing layout, vent diameters, and any settlement or groundwater information , so I may propose to you some way to handle this situation in most economic way.
best regarding
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Abubakr Gameil, R. ENG, M. ASCE®️, SEI Member
Chairman & Director General
Almanassa Engineering International Co. Ltd
Khartoum, Sudan
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