Case 2

Introduction

Type of Building: Residential

In this investigation, the basement area was observed to suffer from severe patches of dampness, stalactites and popping out of concrete were observed on the soffit of  basement slab, sides  and soffits of basement beams  in almost all of the 19 locations inspected. Numerous stalactites and signs of damp patches were observed on the soffit of the basement ceiling below planter boxes. Water ponding was observed to in almost all the planter boxes. Upon the soil removal, it was observed that many of the drain pipes were not even cut to provide the drainage and hence ponding appeared to have started way before the handover. Suspected alkali silica reaction (ASR) in the forms of popping, appeared on soffit of slab, sides and soffit of beams. Penetration of moisture was most probably permeated from the planter box on top, reacted with the reactive aggregates present in the concrete and caused ASR and popping. Size of each popping or popped portion was about 25 to 50mm in diameter. A total of 20 such spots were observed around this location, out of which 13 were about to pop out and the remaining 7 have already popped out with brownish gel showing.