In our vast experience with shower cleaning and restoration, we have pinpointed the most prevalent cause of recurring mold to be associated with the weep holes in shower drains. Often unseen, a pool of stagnant water can accumulate beneath the tile surface without a clear exit path. To elaborate, if you have a tiled shower floor, it's probable that you have a weep-style drain installed. In an ideal scenario, any water permeating below the tile should naturally gravitate towards the drain if the weep system is functioning optimally. However, this is where complications arise.
Our findings reveal that around 90% of weep drains tend to become obstructed, commonly due to builders applying hot tar during the shower's construction phase. This obstruction suggests that your shower may have never effectively drained from the outset. Additionally, blockages in weep drains can stem from remnants of bar soap and hard water deposits, resulting in mineral obstructions.
To spot potential indicators of a clogged weep drain, scrutinize your shower floor for signs such as tile or grout line cracks, the presence of white minerals or calcium seeping through the tile or grout, or external wall damage near the shower curb. These visual cues serve as key markers of underlying issues related to the weep drain system.
