We just bought a 1970s side split in Marda Loop, and the basement smells musty after rain. Is this normal?

A musty smell in your basement after rain is NOT normal and indicates a moisture problem that needs addressing — this is especially common in Calgary's 1970s homes due to aging waterproofing and our expansive clay soils.

Your 1970s side-split in Marda Loop is likely experiencing water infiltration, which is unfortunately common in homes of this era. These homes were built before modern waterproofing standards, and after 50+ years, the original foundation waterproofing has likely deteriorated. Calgary's bentonite clay soils make this worse — the clay expands when wet and contracts when dry, creating constant pressure against your foundation and opening pathways for water.

Common sources of basement moisture in Calgary homes include failing weeping tile systems, cracks in the foundation walls, poor exterior grading, and deteriorated window wells. The musty odor you're smelling is likely mold or mildew growth, which thrives in damp conditions. This isn't just a comfort issue — prolonged moisture can damage your home's structure and create health concerns.

Start with the basics: Check your exterior grading to ensure water flows away from your foundation (minimum 6-inch drop over 10 feet). Clean your gutters and extend downspouts at least 6 feet from the house. Inspect your window wells for standing water or debris. Inside, run a dehumidifier to keep basement humidity below 50% and improve ventilation.

However, given Calgary's challenging soil conditions and the age of your home, you'll likely need professional assessment. A basement waterproofing contractor can inspect for foundation cracks, evaluate your weeping tile system, and determine if exterior waterproofing is needed. This typically involves excavation around the foundation perimeter — a significant project costing $15,000-$40,000 depending on your home's size and access.

Don't ignore this issue — moisture problems only get worse over time, and Calgary's extreme freeze-thaw cycles will expand any existing cracks. Address drainage issues now before they become major structural problems.

Find verified waterproofing contractors who understand Calgary's unique soil challenges in our directory at Calgary Construction Network.

---

Find a Basement Renovations Contractor

Calgary Construction Network connects you with experienced contractors in the directory:

• The Basement renovators ✓
• Mr & Mrs Paintastic Inc ✓
• Venkor Group Inc ✓