Recurring Wet Basement on Bayview: Why Interior-Only Wasn't Enough

When we got the call, the homeowner was frustrated and out about $14,000 to two previous waterproofing companies. They'd installed an interior weeping tile system and a fresh sump pump. Twice. Water kept coming.

The real problem was outside

Inside the basement we could see textbook signs of efflorescence (white mineral residue) two feet up the wall — water was coming THROUGH the wall, not under it. Interior systems can't fix that. They just collect it after it's already inside your home.

We dug along the affected wall, found severe deterioration of the original parging and three vertical cracks that had been hidden behind landscaping for decades. Full exterior membrane, dimple board, new weeping tile, regrading.

Six months later, including through one of the wettest Octobers Markham has seen in a decade, the basement is bone dry.

When interior basement waterproofing IS the right answer

Interior is great for: floor-wall joint seepage, manageable groundwater pressure, and homes where excavation is impossible (e.g. against a neighbour's wall or under a deck you don't want to remove). For chronic wall seepage, exterior is almost always the answer.

Get a free inspection in Markham

If you've noticed dampness, cracks, or musty smells in your basement, don't wait. We offer free on-site inspections across Markham, Unionville, Cornell, Berczy Village, Cathedraltown, Markville and Thornhill — and our work is backed by a written workmanship warranty.