Articles

Practical articles by ASB engineers: where the water comes from, how it is found and what is done about it.

Why a flat roof leaks: the eight causes we find most oftenWhere the water on a top-floor ceiling comes from: ponding, upstands, drains, pipe penetrations, seams, expansion joints, an ageing covering. How an engineer finds the cause and what to do.Read →How to find where the leak is: what the engineer does at an inspectionWhat happens at an engineer's inspection: interview, map of stains, roof or basement check, water test, control opening, written report with an estimate. Why the inspection is paid.Read →Outside or inside: how foundations and basements are waterproofedOn a construction site the foundation is waterproofed from outside, before backfill: spray-applied membrane, drainage, swelling waterstops. In an existing building — from inside: water plugs, injection, crystalline compounds. What works and what doesn't.Read →Roof repair without tear-off: when it works and when it doesn'tA liquid polyurethane membrane over an old roof: the conditions under which a repair without tear-off lasts for years, and the cases where the old covering has to come off. How the base is checked.Read →